From 34f32ffad6e8d4ade76f8a3179734cb7e75e3264 Mon Sep 17 00:00:00 2001 From: zhanxi <2210015294@qq.com> Date: Sun, 5 Apr 2026 15:10:13 +0800 Subject: [PATCH] =?UTF-8?q?=E5=BC=80=E6=BA=90=E8=BD=AF=E4=BB=B6Apache=20Co?= =?UTF-8?q?mmons=20Lang=E4=BC=98=E7=A7=80=E4=BB=A3=E7=A0=81?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ArrayUtils .txt | 9664 ++++++++++++++++++++++++++++++++++++++++++++++ StringUtils .txt | 9243 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 18907 insertions(+) create mode 100644 ArrayUtils .txt create mode 100644 StringUtils .txt diff --git a/ArrayUtils .txt b/ArrayUtils .txt new file mode 100644 index 0000000..3e95e73 --- /dev/null +++ b/ArrayUtils .txt @@ -0,0 +1,9664 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * https://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.commons.lang3; + +import java.lang.reflect.Array; +import java.lang.reflect.Field; +import java.lang.reflect.Method; +import java.lang.reflect.Type; +import java.security.SecureRandom; +import java.util.Arrays; +import java.util.BitSet; +import java.util.Comparator; +import java.util.Date; +import java.util.HashMap; +import java.util.Map; +import java.util.Objects; +import java.util.Random; +import java.util.concurrent.ThreadLocalRandom; +import java.util.function.Function; +import java.util.function.IntFunction; +import java.util.function.Supplier; + +import org.apache.commons.lang3.builder.EqualsBuilder; +import org.apache.commons.lang3.builder.HashCodeBuilder; +import org.apache.commons.lang3.builder.ToStringBuilder; +import org.apache.commons.lang3.builder.ToStringStyle; +import org.apache.commons.lang3.function.FailableFunction; +import org.apache.commons.lang3.mutable.MutableInt; +import org.apache.commons.lang3.stream.IntStreams; +import org.apache.commons.lang3.stream.Streams; + +/** + * Operations on arrays, primitive arrays (like {@code int[]}) and + * primitive wrapper arrays (like {@code Integer[]}). + *

+ * This class tries to handle {@code null} input gracefully. + * An exception will not be thrown for a {@code null} + * array input. However, an Object array that contains a {@code null} + * element may throw an exception. Each method documents its behavior. + *

+ *

+ * #ThreadSafe# + *

+ * + * @since 2.0 + */ +public class ArrayUtils { + + /** + * Bridge class to {@link Math} methods for testing purposes. + */ + static class MathBridge { + static int addExact(final int a, final int b) { + return Math.addExact(a, b); + } + } + + /** + * An empty immutable {@code boolean} array. + */ + public static final boolean[] EMPTY_BOOLEAN_ARRAY = {}; + + /** + * An empty immutable {@link Boolean} array. + */ + public static final Boolean[] EMPTY_BOOLEAN_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@code byte} array. + */ + public static final byte[] EMPTY_BYTE_ARRAY = {}; + + /** + * An empty immutable {@link Byte} array. + */ + public static final Byte[] EMPTY_BYTE_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@code char} array. + */ + public static final char[] EMPTY_CHAR_ARRAY = {}; + + /** + * An empty immutable {@link Character} array. + */ + public static final Character[] EMPTY_CHARACTER_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@link Class} array. + */ + public static final Class[] EMPTY_CLASS_ARRAY = {}; + + /** + * An empty immutable {@code double} array. + */ + public static final double[] EMPTY_DOUBLE_ARRAY = {}; + + /** + * An empty immutable {@link Double} array. + */ + public static final Double[] EMPTY_DOUBLE_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@link Field} array. + * + * @since 3.10 + */ + public static final Field[] EMPTY_FIELD_ARRAY = {}; + + /** + * An empty immutable {@code float} array. + */ + public static final float[] EMPTY_FLOAT_ARRAY = {}; + + /** + * An empty immutable {@link Float} array. + */ + public static final Float[] EMPTY_FLOAT_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@code int} array. + */ + public static final int[] EMPTY_INT_ARRAY = {}; + + /** + * An empty immutable {@link Integer} array. + */ + public static final Integer[] EMPTY_INTEGER_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@code long} array. + */ + public static final long[] EMPTY_LONG_ARRAY = {}; + + /** + * An empty immutable {@link Long} array. + */ + public static final Long[] EMPTY_LONG_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@link Method} array. + * + * @since 3.10 + */ + public static final Method[] EMPTY_METHOD_ARRAY = {}; + + /** + * An empty immutable {@link Object} array. + */ + public static final Object[] EMPTY_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@code short} array. + */ + public static final short[] EMPTY_SHORT_ARRAY = {}; + + /** + * An empty immutable {@link Short} array. + */ + public static final Short[] EMPTY_SHORT_OBJECT_ARRAY = {}; + + /** + * An empty immutable {@link String} array. + */ + public static final String[] EMPTY_STRING_ARRAY = {}; + + /** + * An empty immutable {@link Throwable} array. + * + * @since 3.10 + */ + public static final Throwable[] EMPTY_THROWABLE_ARRAY = {}; + + /** + * An empty immutable {@link Type} array. + * + * @since 3.10 + */ + public static final Type[] EMPTY_TYPE_ARRAY = {}; + + /** + * The index value when an element is not found in a list or array: {@code -1}. + * This value is returned by methods in this class and can also be used in comparisons with values returned by + * various method from {@link java.util.List}. + */ + public static final int INDEX_NOT_FOUND = -1; + + /** + * The {@code SOFT_MAX_ARRAY_LENGTH} constant from Java's internal ArraySupport class. + * + * @since 3.19.0 + * @deprecated This variable will be final in 4.0; to guarantee immutability now, use {@link #SAFE_MAX_ARRAY_LENGTH}. + */ + @Deprecated + public static int SOFT_MAX_ARRAY_LENGTH = Integer.MAX_VALUE - 8; + + /** + * The {@code MAX_ARRAY_LENGTH} constant from Java's internal ArraySupport class. + * + * @since 3.21.0 + */ + public static final int SAFE_MAX_ARRAY_LENGTH = Integer.MAX_VALUE - 8; + + /** + * Copies the given array and adds the given element at the end of the new array. + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, true)          = [true]
+     * ArrayUtils.add([true], false)       = [true, false]
+     * ArrayUtils.add([true, false], true) = [true, false, true]
+     * 
+ * + * @param array the array to copy and add the element to, may be {@code null}. + * @param element the object to add at the last index of the new array. + * @return A new array containing the existing elements plus the new element. + * @since 2.1 + */ + public static boolean[] add(final boolean[] array, final boolean element) { + final boolean[] newArray = (boolean[]) copyArrayGrow1(array, Boolean.TYPE); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0, true)          = [true]
+     * ArrayUtils.add([true], 0, false)       = [false, true]
+     * ArrayUtils.add([false], 1, true)       = [false, true]
+     * ArrayUtils.add([true, false], 1, true) = [true, true, false]
+     * 
+ * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index > array.length). + * @deprecated this method has been superseded by {@link #insert(int, boolean[], boolean...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static boolean[] add(final boolean[] array, final int index, final boolean element) { + return (boolean[]) add(array, index, Boolean.valueOf(element), Boolean.TYPE); + } + + /** + * Copies the given array and adds the given element at the end of the new array. + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0)   = [0]
+     * ArrayUtils.add([1], 0)    = [1, 0]
+     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
+     * 
+ * + * @param array the array to copy and add the element to, may be {@code null}. + * @param element the object to add at the last index of the new array. + * @return A new array containing the existing elements plus the new element. + * @since 2.1 + */ + public static byte[] add(final byte[] array, final byte element) { + final byte[] newArray = (byte[]) copyArrayGrow1(array, Byte.TYPE); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add([1], 0, 2)         = [2, 1]
+     * ArrayUtils.add([2, 6], 2, 3)      = [2, 6, 3]
+     * ArrayUtils.add([2, 6], 0, 1)      = [1, 2, 6]
+     * ArrayUtils.add([2, 6, 3], 2, 1)   = [2, 6, 1, 3]
+     * 
+ * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range. + * (index < 0 || index > array.length). + * @deprecated this method has been superseded by {@link #insert(int, byte[], byte...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static byte[] add(final byte[] array, final int index, final byte element) { + return (byte[]) add(array, index, Byte.valueOf(element), Byte.TYPE); + } + + /** + * Copies the given array and adds the given element at the end of the new array. + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, '0')       = ['0']
+     * ArrayUtils.add(['1'], '0')      = ['1', '0']
+     * ArrayUtils.add(['1', '0'], '1') = ['1', '0', '1']
+     * 
+ * + * @param array the array to copy and add the element to, may be {@code null}. + * @param element the object to add at the last index of the new array. + * @return A new array containing the existing elements plus the new element. + * @since 2.1 + */ + public static char[] add(final char[] array, final char element) { + final char[] newArray = (char[]) copyArrayGrow1(array, Character.TYPE); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0, 'a')            = ['a']
+     * ArrayUtils.add(['a'], 0, 'b')           = ['b', 'a']
+     * ArrayUtils.add(['a', 'b'], 0, 'c')      = ['c', 'a', 'b']
+     * ArrayUtils.add(['a', 'b'], 1, 'k')      = ['a', 'k', 'b']
+     * ArrayUtils.add(['a', 'b', 'c'], 1, 't') = ['a', 't', 'b', 'c']
+     * 
+ * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range. + * (index < 0 || index > array.length). + * @deprecated this method has been superseded by {@link #insert(int, char[], char...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static char[] add(final char[] array, final int index, final char element) { + return (char[]) add(array, index, Character.valueOf(element), Character.TYPE); + } + + /** + * Copies the given array and adds the given element at the end of the new array. + * + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0)   = [0]
+     * ArrayUtils.add([1], 0)    = [1, 0]
+     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
+     * 
+ * + * @param array the array to copy and add the element to, may be {@code null}. + * @param element the object to add at the last index of the new array. + * @return A new array containing the existing elements plus the new element. + * @since 2.1 + */ + public static double[] add(final double[] array, final double element) { + final double[] newArray = (double[]) copyArrayGrow1(array, Double.TYPE); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add([1.1], 0, 2.2)              = [2.2, 1.1]
+     * ArrayUtils.add([2.3, 6.4], 2, 10.5)        = [2.3, 6.4, 10.5]
+     * ArrayUtils.add([2.6, 6.7], 0, -4.8)        = [-4.8, 2.6, 6.7]
+     * ArrayUtils.add([2.9, 6.0, 0.3], 2, 1.0)    = [2.9, 6.0, 1.0, 0.3]
+     * 
+ * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index > array.length). + * @deprecated this method has been superseded by {@link #insert(int, double[], double...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static double[] add(final double[] array, final int index, final double element) { + return (double[]) add(array, index, Double.valueOf(element), Double.TYPE); + } + + /** + * Copies the given array and adds the given element at the end of the new array. + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0)   = [0]
+     * ArrayUtils.add([1], 0)    = [1, 0]
+     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
+     * 
+ * + * @param array the array to copy and add the element to, may be {@code null}. + * @param element the object to add at the last index of the new array. + * @return A new array containing the existing elements plus the new element. + * @since 2.1 + */ + public static float[] add(final float[] array, final float element) { + final float[] newArray = (float[]) copyArrayGrow1(array, Float.TYPE); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add([1.1f], 0, 2.2f)               = [2.2f, 1.1f]
+     * ArrayUtils.add([2.3f, 6.4f], 2, 10.5f)        = [2.3f, 6.4f, 10.5f]
+     * ArrayUtils.add([2.6f, 6.7f], 0, -4.8f)        = [-4.8f, 2.6f, 6.7f]
+     * ArrayUtils.add([2.9f, 6.0f, 0.3f], 2, 1.0f)   = [2.9f, 6.0f, 1.0f, 0.3f]
+     * 
+ * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index > array.length). + * @deprecated this method has been superseded by {@link #insert(int, float[], float...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static float[] add(final float[] array, final int index, final float element) { + return (float[]) add(array, index, Float.valueOf(element), Float.TYPE); + } + + /** + * Copies the given array and adds the given element at the end of the new array. + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0)   = [0]
+     * ArrayUtils.add([1], 0)    = [1, 0]
+     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
+     * 
+ * + * @param array the array to copy and add the element to, may be {@code null}. + * @param element the object to add at the last index of the new array. + * @return A new array containing the existing elements plus the new element. + * @since 2.1 + */ + public static int[] add(final int[] array, final int element) { + final int[] newArray = (int[]) copyArrayGrow1(array, Integer.TYPE); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add([1], 0, 2)         = [2, 1]
+     * ArrayUtils.add([2, 6], 2, 10)     = [2, 6, 10]
+     * ArrayUtils.add([2, 6], 0, -4)     = [-4, 2, 6]
+     * ArrayUtils.add([2, 6, 3], 2, 1)   = [2, 6, 1, 3]
+     * 
+ * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index > array.length). + * @deprecated this method has been superseded by {@link #insert(int, int[], int...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static int[] add(final int[] array, final int index, final int element) { + return (int[]) add(array, index, Integer.valueOf(element), Integer.TYPE); + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add([1L], 0, 2L)           = [2L, 1L]
+     * ArrayUtils.add([2L, 6L], 2, 10L)      = [2L, 6L, 10L]
+     * ArrayUtils.add([2L, 6L], 0, -4L)      = [-4L, 2L, 6L]
+     * ArrayUtils.add([2L, 6L, 3L], 2, 1L)   = [2L, 6L, 1L, 3L]
+     * 
+ * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index > array.length). + * @deprecated this method has been superseded by {@link #insert(int, long[], long...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static long[] add(final long[] array, final int index, final long element) { + return (long[]) add(array, index, Long.valueOf(element), Long.TYPE); + } + + /** + * Copies the given array and adds the given element at the end of the new array. + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0)   = [0]
+     * ArrayUtils.add([1], 0)    = [1, 0]
+     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
+     * 
+ * + * @param array the array to copy and add the element to, may be {@code null}. + * @param element the object to add at the last index of the new array. + * @return A new array containing the existing elements plus the new element. + * @since 2.1 + */ + public static long[] add(final long[] array, final long element) { + final long[] newArray = (long[]) copyArrayGrow1(array, Long.TYPE); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Underlying implementation of add(array, index, element) methods. + * The last parameter is the class, which may not equal element.getClass + * for primitives. + * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @param clazz the type of the element being added. + * @return A new array containing the existing elements and the new element. + */ + private static Object add(final Object array, final int index, final Object element, final Class clazz) { + if (array == null) { + if (index != 0) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: 0"); + } + final Object joinedArray = Array.newInstance(clazz, 1); + Array.set(joinedArray, 0, element); + return joinedArray; + } + final int length = Array.getLength(array); + if (index > length || index < 0) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + length); + } + final Object result = arraycopy(array, 0, 0, index, () -> Array.newInstance(clazz, length + 1)); + Array.set(result, index, element); + if (index < length) { + System.arraycopy(array, index, result, index + 1, length - index); + } + return result; + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add([1], 0, 2)         = [2, 1]
+     * ArrayUtils.add([2, 6], 2, 10)     = [2, 6, 10]
+     * ArrayUtils.add([2, 6], 0, -4)     = [-4, 2, 6]
+     * ArrayUtils.add([2, 6, 3], 2, 1)   = [2, 6, 1, 3]
+     * 
+ * + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range + * (index < 0 || index > array.length). + * @deprecated this method has been superseded by {@link #insert(int, short[], short...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static short[] add(final short[] array, final int index, final short element) { + return (short[]) add(array, index, Short.valueOf(element), Short.TYPE); + } + + /** + * Copies the given array and adds the given element at the end of the new array. + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0)   = [0]
+     * ArrayUtils.add([1], 0)    = [1, 0]
+     * ArrayUtils.add([1, 0], 1) = [1, 0, 1]
+     * 
+ * + * @param array the array to copy and add the element to, may be {@code null}. + * @param element the object to add at the last index of the new array. + * @return A new array containing the existing elements plus the new element. + * @since 2.1 + */ + public static short[] add(final short[] array, final short element) { + final short[] newArray = (short[]) copyArrayGrow1(array, Short.TYPE); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Inserts the specified element at the specified position in the array. + * Shifts the element currently at that position (if any) and any subsequent + * elements to the right (adds one to their indices). + *

+ * This method returns a new array with the same elements of the input + * array plus the given element on the specified position. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element. + *

+ *
+     * ArrayUtils.add(null, 0, null)      = Throws {@link IllegalArgumentException}
+     * ArrayUtils.add(null, 0, "a")       = ["a"]
+     * ArrayUtils.add(["a"], 1, null)     = ["a", null]
+     * ArrayUtils.add(["a"], 1, "b")      = ["a", "b"]
+     * ArrayUtils.add(["a", "b"], 3, "c") = ["a", "b", "c"]
+     * 
+ * + * @param the component type of the array. + * @param array the array to add the element to, may be {@code null}. + * @param index the position of the new object. + * @param element the object to add. + * @return A new array containing the existing elements and the new element. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index > array.length). + * @throws IllegalArgumentException if both array and element are null. + * @deprecated this method has been superseded by {@link #insert(int, Object[], Object...) insert(int, T[], T...)} and + * may be removed in a future release. Please note the handling of {@code null} input arrays differs + * in the new method: inserting {@code X} into a {@code null} array results in {@code null} not {@code X}. + */ + @Deprecated + public static T[] add(final T[] array, final int index, final T element) { + final Class clazz; + if (array != null) { + clazz = getComponentType(array); + } else if (element != null) { + clazz = ObjectUtils.getClass(element); + } else { + throw new IllegalArgumentException("Array and element cannot both be null"); + } + return (T[]) add(array, index, element, clazz); + } + + /** + * Copies the given array and adds the given element at the end of the new array. + *

+ * The new array contains the same elements of the input + * array plus the given element in the last position. The component type of + * the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned + * whose component type is the same as the element, unless the element itself is null, + * in which case the return type is Object[] + *

+ *
+     * ArrayUtils.add(null, null)      = Throws {@link IllegalArgumentException}
+     * ArrayUtils.add(null, "a")       = ["a"]
+     * ArrayUtils.add(["a"], null)     = ["a", null]
+     * ArrayUtils.add(["a"], "b")      = ["a", "b"]
+     * ArrayUtils.add(["a", "b"], "c") = ["a", "b", "c"]
+     * 
+ * + * @param the component type of the array. + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add, may be {@code null}. + * @return A new array containing the existing elements plus the new element + * The returned array type will be that of the input array (unless null), + * in which case it will have the same type as the element. + * If both are null, an IllegalArgumentException is thrown. + * @throws IllegalArgumentException if both arguments are null. + * @since 2.1 + */ + public static T[] add(final T[] array, final T element) { + final Class type; + if (array != null) { + type = array.getClass().getComponentType(); + } else if (element != null) { + type = element.getClass(); + } else { + throw new IllegalArgumentException("Arguments cannot both be null"); + } + @SuppressWarnings("unchecked") // type must be T + final + T[] newArray = (T[]) copyArrayGrow1(array, type); + newArray[newArray.length - 1] = element; + return newArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * 
+ * + * @param array1 the first array whose elements are added to the new array. + * @param array2 the second array whose elements are added to the new array. + * @return The new boolean[] array or {@code null}. + * @since 2.1 + */ + public static boolean[] addAll(final boolean[] array1, final boolean... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final boolean[] joinedArray = new boolean[array1.length + array2.length]; + System.arraycopy(array1, 0, joinedArray, 0, array1.length); + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + return joinedArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * 
+ * + * @param array1 the first array whose elements are added to the new array. + * @param array2 the second array whose elements are added to the new array. + * @return The new byte[] array or {@code null}. + * @since 2.1 + */ + public static byte[] addAll(final byte[] array1, final byte... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final byte[] joinedArray = new byte[array1.length + array2.length]; + System.arraycopy(array1, 0, joinedArray, 0, array1.length); + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + return joinedArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * 
+ * + * @param array1 the first array whose elements are added to the new array. + * @param array2 the second array whose elements are added to the new array. + * @return The new char[] array or {@code null}. + * @since 2.1 + */ + public static char[] addAll(final char[] array1, final char... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final char[] joinedArray = new char[array1.length + array2.length]; + System.arraycopy(array1, 0, joinedArray, 0, array1.length); + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + return joinedArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * 
+ * + * @param array1 the first array whose elements are added to the new array. + * @param array2 the second array whose elements are added to the new array. + * @return The new double[] array or {@code null}. + * @since 2.1 + */ + public static double[] addAll(final double[] array1, final double... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final double[] joinedArray = new double[array1.length + array2.length]; + System.arraycopy(array1, 0, joinedArray, 0, array1.length); + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + return joinedArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * 
+ * + * @param array1 the first array whose elements are added to the new array. + * @param array2 the second array whose elements are added to the new array. + * @return The new float[] array or {@code null}. + * @since 2.1 + */ + public static float[] addAll(final float[] array1, final float... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final float[] joinedArray = new float[array1.length + array2.length]; + System.arraycopy(array1, 0, joinedArray, 0, array1.length); + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + return joinedArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * 
+ * + * @param array1 the first array whose elements are added to the new array. + * @param array2 the second array whose elements are added to the new array. + * @return The new int[] array or {@code null}. + * @since 2.1 + */ + public static int[] addAll(final int[] array1, final int... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final int[] joinedArray = new int[array1.length + array2.length]; + System.arraycopy(array1, 0, joinedArray, 0, array1.length); + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + return joinedArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * 
+ * + * @param array1 the first array whose elements are added to the new array. + * @param array2 the second array whose elements are added to the new array. + * @return The new long[] array or {@code null}. + * @since 2.1 + */ + public static long[] addAll(final long[] array1, final long... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final long[] joinedArray = new long[array1.length + array2.length]; + System.arraycopy(array1, 0, joinedArray, 0, array1.length); + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + return joinedArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * 
+ * + * @param array1 the first array whose elements are added to the new array. + * @param array2 the second array whose elements are added to the new array. + * @return The new short[] array or {@code null}. + * @since 2.1 + */ + public static short[] addAll(final short[] array1, final short... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final short[] joinedArray = new short[array1.length + array2.length]; + System.arraycopy(array1, 0, joinedArray, 0, array1.length); + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + return joinedArray; + } + + /** + * Adds all the elements of the given arrays into a new array. + *

+ * The new array contains all of the element of {@code array1} followed + * by all of the elements {@code array2}. When an array is returned, it is always + * a new array. + *

+ *
+     * ArrayUtils.addAll(null, null)     = null
+     * ArrayUtils.addAll(array1, null)   = cloned copy of array1
+     * ArrayUtils.addAll(null, array2)   = cloned copy of array2
+     * ArrayUtils.addAll([], [])         = []
+     * ArrayUtils.addAll(null, null)     = null
+     * ArrayUtils.addAll([null], [null]) = [null, null]
+     * ArrayUtils.addAll(["a", "b", "c"], ["1", "2", "3"]) = ["a", "b", "c", "1", "2", "3"]
+     * 
+ * + * @param the component type of the array. + * @param array1 the first array whose elements are added to the new array, may be {@code null}. + * @param array2 the second array whose elements are added to the new array, may be {@code null}. + * @return The new array, {@code null} if both arrays are {@code null}. + * The type of the new array is the type of the first array, + * unless the first array is null, in which case the type is the same as the second array. + * @throws IllegalArgumentException if the array types are incompatible. + * @since 2.1 + */ + public static T[] addAll(final T[] array1, @SuppressWarnings("unchecked") final T... array2) { + if (array1 == null) { + return clone(array2); + } + if (array2 == null) { + return clone(array1); + } + final Class type1 = getComponentType(array1); + final T[] joinedArray = arraycopy(array1, 0, 0, array1.length, () -> newInstance(type1, array1.length + array2.length)); + try { + System.arraycopy(array2, 0, joinedArray, array1.length, array2.length); + } catch (final ArrayStoreException ase) { + // Check if problem was due to incompatible types + /* + * We do this here, rather than before the copy because: - it would be a wasted check most of the time - safer, in case check turns out to be too + * strict + */ + final Class type2 = array2.getClass().getComponentType(); + if (!type1.isAssignableFrom(type2)) { + throw new IllegalArgumentException("Cannot store " + type2.getName() + " in an array of " + type1.getName(), ase); + } + throw ase; // No, so rethrow original + } + return joinedArray; + } + + /** + * Safely adds the length of an array to a running total, checking for overflow. + * + * @param totalLength the current accumulated length + * @param array the array whose length should be added (can be {@code null}, + * in which case its length is considered 0) + * @return the new total length after adding the array's length + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + */ + private static int addExact(final int totalLength, final Object array) { + try { + final int length = MathBridge.addExact(totalLength, getLength(array)); + if (length > SAFE_MAX_ARRAY_LENGTH) { + throw new IllegalArgumentException("Total arrays length exceed " + SAFE_MAX_ARRAY_LENGTH); + } + return length; + } catch (final ArithmeticException exception) { + throw new IllegalArgumentException("Total arrays length exceed " + SAFE_MAX_ARRAY_LENGTH); + } + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element. + *

+ *
+     * ArrayUtils.addFirst(null, true)          = [true]
+     * ArrayUtils.addFirst([true], false)       = [false, true]
+     * ArrayUtils.addFirst([true, false], true) = [true, true, false]
+     * 
+ * + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. + * @since 3.10 + */ + public static boolean[] addFirst(final boolean[] array, final boolean element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element. + *

+ *
+     * ArrayUtils.addFirst(null, 1)   = [1]
+     * ArrayUtils.addFirst([1], 0)    = [0, 1]
+     * ArrayUtils.addFirst([1, 0], 1) = [1, 1, 0]
+     * 
+ * + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. + * @since 3.10 + */ + public static byte[] addFirst(final byte[] array, final byte element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element. + *

+ *
+     * ArrayUtils.addFirst(null, '1')       = ['1']
+     * ArrayUtils.addFirst(['1'], '0')      = ['0', '1']
+     * ArrayUtils.addFirst(['1', '0'], '1') = ['1', '1', '0']
+     * 
+ * + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. + * @since 3.10 + */ + public static char[] addFirst(final char[] array, final char element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element. + *

+ *
+     * ArrayUtils.addFirst(null, 1)   = [1]
+     * ArrayUtils.addFirst([1], 0)    = [0, 1]
+     * ArrayUtils.addFirst([1, 0], 1) = [1, 1, 0]
+     * 
+ * + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. + * @since 3.10 + */ + public static double[] addFirst(final double[] array, final double element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element. + *

+ *
+     * ArrayUtils.addFirst(null, 1)   = [1]
+     * ArrayUtils.addFirst([1], 0)    = [0, 1]
+     * ArrayUtils.addFirst([1, 0], 1) = [1, 1, 0]
+     * 
+ * + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. + * @since 3.10 + */ + public static float[] addFirst(final float[] array, final float element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element. + *

+ *
+     * ArrayUtils.addFirst(null, 1)   = [1]
+     * ArrayUtils.addFirst([1], 0)    = [0, 1]
+     * ArrayUtils.addFirst([1, 0], 1) = [1, 1, 0]
+     * 
+ * + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. + * @since 3.10 + */ + public static int[] addFirst(final int[] array, final int element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element. + *

+ *
+     * ArrayUtils.addFirst(null, 1)   = [1]
+     * ArrayUtils.addFirst([1], 0)    = [0, 1]
+     * ArrayUtils.addFirst([1, 0], 1) = [1, 1, 0]
+     * 
+ * + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. + * @since 3.10 + */ + public static long[] addFirst(final long[] array, final long element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element. + *

+ *
+     * ArrayUtils.addFirst(null, 1)   = [1]
+     * ArrayUtils.addFirst([1], 0)    = [0, 1]
+     * ArrayUtils.addFirst([1, 0], 1) = [1, 1, 0]
+     * 
+ * + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. + * @since 3.10 + */ + public static short[] addFirst(final short[] array, final short element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * Copies the given array and adds the given element at the beginning of the new array. + *

+ * The new array contains the same elements of the input array plus the given element in the first position. The + * component type of the new array is the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, a new one element array is returned whose component type is the same as the + * element, unless the element itself is null, in which case the return type is Object[] + *

+ *
+     * ArrayUtils.addFirst(null, null)      = Throws {@link IllegalArgumentException}
+     * ArrayUtils.addFirst(null, "a")       = ["a"]
+     * ArrayUtils.addFirst(["a"], null)     = [null, "a"]
+     * ArrayUtils.addFirst(["a"], "b")      = ["b", "a"]
+     * ArrayUtils.addFirst(["a", "b"], "c") = ["c", "a", "b"]
+     * 
+ * + * @param the component type of the array. + * @param array the array to "add" the element to, may be {@code null}. + * @param element the object to add, may be {@code null}. + * @return A new array containing the existing elements plus the new element The returned array type will be that of + * the input array (unless null), in which case it will have the same type as the element. If both are null, + * an IllegalArgumentException is thrown. + * @throws IllegalArgumentException if both arguments are null. + * @since 3.10 + */ + public static T[] addFirst(final T[] array, final T element) { + return array == null ? add(array, element) : insert(0, array, element); + } + + /** + * A fluent version of {@link System#arraycopy(Object, int, Object, int, int)} that returns the destination array. + * + * @param the type. + * @param source the source array. + * @param sourcePos starting position in the source array. + * @param destPos starting position in the destination data. + * @param length the number of array elements to be copied. + * @param allocator allocates the array to populate and return. + * @return dest + * @throws IndexOutOfBoundsException if copying would cause access of data outside array bounds. + * @throws ArrayStoreException if an element in the {@code src} array could not be stored into the {@code dest} array because of a type + * mismatch. + * @throws NullPointerException if either {@code src} or {@code dest} is {@code null}. + * @since 3.15.0 + */ + public static T arraycopy(final T source, final int sourcePos, final int destPos, final int length, final Function allocator) { + return arraycopy(source, sourcePos, allocator.apply(length), destPos, length); + } + + /** + * A fluent version of {@link System#arraycopy(Object, int, Object, int, int)} that returns the destination array. + * + * @param the type. + * @param source the source array. + * @param sourcePos starting position in the source array. + * @param destPos starting position in the destination data. + * @param length the number of array elements to be copied. + * @param allocator allocates the array to populate and return. + * @return dest + * @throws IndexOutOfBoundsException if copying would cause access of data outside array bounds. + * @throws ArrayStoreException if an element in the {@code src} array could not be stored into the {@code dest} array because of a type + * mismatch. + * @throws NullPointerException if either {@code src} or {@code dest} is {@code null}. + * @since 3.15.0 + */ + public static T arraycopy(final T source, final int sourcePos, final int destPos, final int length, final Supplier allocator) { + return arraycopy(source, sourcePos, allocator.get(), destPos, length); + } + + /** + * A fluent version of {@link System#arraycopy(Object, int, Object, int, int)} that returns the destination array. + * + * @param the type. + * @param source the source array. + * @param sourcePos starting position in the source array. + * @param dest the destination array. + * @param destPos starting position in the destination data. + * @param length the number of array elements to be copied. + * @return dest + * @throws IndexOutOfBoundsException if copying would cause access of data outside array bounds. + * @throws ArrayStoreException if an element in the {@code src} array could not be stored into the {@code dest} array because of a type + * mismatch. + * @throws NullPointerException if either {@code src} or {@code dest} is {@code null}. + * @since 3.15.0 + */ + public static T arraycopy(final T source, final int sourcePos, final T dest, final int destPos, final int length) { + System.arraycopy(source, sourcePos, dest, destPos, length); + return dest; + } + + /** + * Clones an array or returns {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the array to clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static boolean[] clone(final boolean[] array) { + return array != null ? array.clone() : null; + } + + /** + * Clones an array or returns {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the array to clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static byte[] clone(final byte[] array) { + return array != null ? array.clone() : null; + } + + /** + * Clones an array or returns {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the array to clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static char[] clone(final char[] array) { + return array != null ? array.clone() : null; + } + + /** + * Clones an array or returns {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the array to clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static double[] clone(final double[] array) { + return array != null ? array.clone() : null; + } + + /** + * Clones an array or returns {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the array to clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static float[] clone(final float[] array) { + return array != null ? array.clone() : null; + } + + /** + * Clones an array or returns {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the array to clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static int[] clone(final int[] array) { + return array != null ? array.clone() : null; + } + + /** + * Clones an array or returns {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the array to clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static long[] clone(final long[] array) { + return array != null ? array.clone() : null; + } + + /** + * Clones an array or returns {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the array to clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static short[] clone(final short[] array) { + return array != null ? array.clone() : null; + } + + /** + * Shallow clones an array or returns {@code null}. + *

+ * The objects in the array are not cloned, thus there is no special handling for multi-dimensional arrays. + *

+ *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param the component type of the array. + * @param array the array to shallow clone, may be {@code null}. + * @return the cloned array, {@code null} if {@code null} input. + */ + public static T[] clone(final T[] array) { + return array != null ? array.clone() : null; + } + + /** + * Concatenates multiple boolean arrays into a single array. + *

+ * This method combines all input arrays in the order they are provided, + * creating a new array that contains all elements from the input arrays. + * The resulting array length is the sum of lengths of all non-null input arrays. + *

+ * + * @param arrays the arrays to concatenate. Can be empty, contain nulls, + * or be null itself (treated as empty varargs). + * @return a new boolean array containing all elements from the input arrays + * in the order they appear, or an empty array if no elements are present. + * @throws NullPointerException if the input array of arrays is null. + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + * @since 3.21.0 + */ + public static boolean[] concat(boolean[]... arrays) { + int totalLength = 0; + for (boolean[] array : arrays) { + totalLength = addExact(totalLength, array); + } + final boolean[] result = new boolean[totalLength]; + int currentPos = 0; + for (boolean[] array : arrays) { + if (array != null && array.length > 0) { + System.arraycopy(array, 0, result, currentPos, array.length); + currentPos += array.length; + } + } + return result; + } + + /** + * Concatenates multiple byte arrays into a single array. + *

+ * This method combines all input arrays in the order they are provided, + * creating a new array that contains all elements from the input arrays. + * The resulting array length is the sum of lengths of all non-null input arrays. + *

+ * + * @param arrays the arrays to concatenate. Can be empty, contain nulls, + * or be null itself (treated as empty varargs). + * @return a new byte array containing all elements from the input arrays + * in the order they appear, or an empty array if no elements are present. + * @throws NullPointerException if the input array of arrays is null. + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + * @since 3.21.0 + */ + public static byte[] concat(byte[]... arrays) { + int totalLength = 0; + for (byte[] array : arrays) { + totalLength = addExact(totalLength, array); + } + final byte[] result = new byte[totalLength]; + int currentPos = 0; + for (byte[] array : arrays) { + if (array != null && array.length > 0) { + System.arraycopy(array, 0, result, currentPos, array.length); + currentPos += array.length; + } + } + return result; + } + + /** + * Concatenates multiple char arrays into a single array. + *

+ * This method combines all input arrays in the order they are provided, + * creating a new array that contains all elements from the input arrays. + * The resulting array length is the sum of lengths of all non-null input arrays. + *

+ * + * @param arrays the arrays to concatenate. Can be empty, contain nulls, + * or be null itself (treated as empty varargs). + * @return a new char array containing all elements from the input arrays + * in the order they appear, or an empty array if no elements are present. + * @throws NullPointerException if the input array of arrays is null. + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + * @since 3.21.0 + */ + public static char[] concat(char[]... arrays) { + int totalLength = 0; + for (char[] array : arrays) { + totalLength = addExact(totalLength, array); + } + final char[] result = new char[totalLength]; + int currentPos = 0; + for (char[] array : arrays) { + if (array != null && array.length > 0) { + System.arraycopy(array, 0, result, currentPos, array.length); + currentPos += array.length; + } + } + return result; + } + + /** + * Concatenates multiple double arrays into a single array. + *

+ * This method combines all input arrays in the order they are provided, + * creating a new array that contains all elements from the input arrays. + * The resulting array length is the sum of lengths of all non-null input arrays. + *

+ * + * @param arrays the arrays to concatenate. Can be empty, contain nulls, + * or be null itself (treated as empty varargs). + * @return a new double array containing all elements from the input arrays + * in the order they appear, or an empty array if no elements are present. + * @throws NullPointerException if the input array of arrays is null. + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + * @since 3.21.0 + */ + public static double[] concat(double[]... arrays) { + int totalLength = 0; + for (double[] array : arrays) { + totalLength = addExact(totalLength, array); + } + final double[] result = new double[totalLength]; + int currentPos = 0; + for (double[] array : arrays) { + if (array != null && array.length > 0) { + System.arraycopy(array, 0, result, currentPos, array.length); + currentPos += array.length; + } + } + return result; + } + + /** + * Concatenates multiple float arrays into a single array. + *

+ * This method combines all input arrays in the order they are provided, + * creating a new array that contains all elements from the input arrays. + * The resulting array length is the sum of lengths of all non-null input arrays. + *

+ * + * @param arrays the arrays to concatenate. Can be empty, contain nulls, + * or be null itself (treated as empty varargs). + * @return a new float array containing all elements from the input arrays + * in the order they appear, or an empty array if no elements are present. + * @throws NullPointerException if the input array of arrays is null. + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + * @since 3.21.0 + */ + public static float[] concat(float[]... arrays) { + int totalLength = 0; + for (float[] array : arrays) { + totalLength = addExact(totalLength, array); + } + final float[] result = new float[totalLength]; + int currentPos = 0; + for (float[] array : arrays) { + if (array != null && array.length > 0) { + System.arraycopy(array, 0, result, currentPos, array.length); + currentPos += array.length; + } + } + return result; + } + + /** + * Concatenates multiple int arrays into a single array. + *

+ * This method combines all input arrays in the order they are provided, + * creating a new array that contains all elements from the input arrays. + * The resulting array length is the sum of lengths of all non-null input arrays. + *

+ * + * @param arrays the arrays to concatenate. Can be empty, contain nulls, + * or be null itself (treated as empty varargs). + * @return a new int array containing all elements from the input arrays + * in the order they appear, or an empty array if no elements are present. + * @throws NullPointerException if the input array of arrays is null. + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + * @since 3.21.0 + */ + public static int[] concat(int[]... arrays) { + int totalLength = 0; + for (int[] array : arrays) { + totalLength = addExact(totalLength, array); + } + final int[] result = new int[totalLength]; + int currentPos = 0; + for (int[] array : arrays) { + if (array != null && array.length > 0) { + System.arraycopy(array, 0, result, currentPos, array.length); + currentPos += array.length; + } + } + return result; + } + + /** + * Concatenates multiple long arrays into a single array. + *

+ * This method combines all input arrays in the order they are provided, + * creating a new array that contains all elements from the input arrays. + * The resulting array length is the sum of lengths of all non-null input arrays. + *

+ * + * @param arrays the arrays to concatenate. Can be empty, contain nulls, + * or be null itself (treated as empty varargs). + * @return a new long array containing all elements from the input arrays + * in the order they appear, or an empty array if no elements are present. + * @throws NullPointerException if the input array of arrays is null. + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + * @since 3.21.0 + */ + public static long[] concat(long[]... arrays) { + int totalLength = 0; + for (long[] array : arrays) { + totalLength = addExact(totalLength, array); + } + final long[] result = new long[totalLength]; + int currentPos = 0; + for (long[] array : arrays) { + if (array != null && array.length > 0) { + System.arraycopy(array, 0, result, currentPos, array.length); + currentPos += array.length; + } + } + return result; + } + + /** + * Concatenates multiple short arrays into a single array. + *

+ * This method combines all input arrays in the order they are provided, + * creating a new array that contains all elements from the input arrays. + * The resulting array length is the sum of lengths of all non-null input arrays. + *

+ * + * @param arrays the arrays to concatenate. Can be empty, contain nulls, + * or be null itself (treated as empty varargs). + * @return a new short array containing all elements from the input arrays + * in the order they appear, or an empty array if no elements are present. + * @throws NullPointerException if the input array of arrays is null. + * @throws IllegalArgumentException if total arrays length exceed {@link ArrayUtils#SAFE_MAX_ARRAY_LENGTH}. + * @since 3.21.0 + */ + public static short[] concat(short[]... arrays) { + int totalLength = 0; + for (short[] array : arrays) { + totalLength = addExact(totalLength, array); + } + final short[] result = new short[totalLength]; + int currentPos = 0; + for (short[] array : arrays) { + if (array != null && array.length > 0) { + System.arraycopy(array, 0, result, currentPos, array.length); + currentPos += array.length; + } + } + return result; + } + + /** + * Checks if the value is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @return {@code true} if the array contains the object. + */ + public static boolean contains(final boolean[] array, final boolean valueToFind) { + return indexOf(array, valueToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if the value is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(byte[])} and {@link Arrays#binarySearch(byte[], byte)}. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @return {@code true} if the array contains the object. + */ + public static boolean contains(final byte[] array, final byte valueToFind) { + return indexOf(array, valueToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if the value is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(char[])} and {@link Arrays#binarySearch(char[], char)}. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @return {@code true} if the array contains the object. + * @since 2.1 + */ + public static boolean contains(final char[] array, final char valueToFind) { + return indexOf(array, valueToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if the value is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(double[])} and {@link Arrays#binarySearch(double[], double)}. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @return {@code true} if the array contains the object. + */ + public static boolean contains(final double[] array, final double valueToFind) { + return indexOf(array, valueToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if a value falling within the given tolerance is in the + * given array. If the array contains a value within the inclusive range + * defined by (value - tolerance) to (value + tolerance). + *

+ * The method returns {@code false} if a {@code null} array + * is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(double[])} and {@link Arrays#binarySearch(double[], double)}. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @param tolerance the array contains the tolerance of the search. + * @return true if value falling within tolerance is in array. + */ + public static boolean contains(final double[] array, final double valueToFind, final double tolerance) { + return indexOf(array, valueToFind, 0, tolerance) != INDEX_NOT_FOUND; + } + + /** + * Checks if the value is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(float[])} and {@link Arrays#binarySearch(float[], float)}. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @return {@code true} if the array contains the object. + */ + public static boolean contains(final float[] array, final float valueToFind) { + return indexOf(array, valueToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if the value is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(int[])} and {@link Arrays#binarySearch(int[], int)}. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @return {@code true} if the array contains the object. + */ + public static boolean contains(final int[] array, final int valueToFind) { + return indexOf(array, valueToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if the value is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(long[])} and {@link Arrays#binarySearch(long[], long)}. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @return {@code true} if the array contains the object. + */ + public static boolean contains(final long[] array, final long valueToFind) { + return indexOf(array, valueToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if the object is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(Object[], Comparator)} and {@link Arrays#binarySearch(Object[], Object)}. + *

+ * + * @param array the array to search, may be {@code null}. + * @param objectToFind the object to find, may be {@code null}. + * @return {@code true} if the array contains the object. + */ + public static boolean contains(final Object[] array, final Object objectToFind) { + return indexOf(array, objectToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if the value is in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(short[])} and {@link Arrays#binarySearch(short[], short)}. + *

+ * + * @param array the array to search. + * @param valueToFind the value to find. + * @return {@code true} if the array contains the object. + */ + public static boolean contains(final short[] array, final short valueToFind) { + return indexOf(array, valueToFind) != INDEX_NOT_FOUND; + } + + /** + * Checks if any of the ints are in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(int[])} and {@link Arrays#binarySearch(int[], int)}. + *

+ * + * @param array the array to search. + * @param objectsToFind any of the ints to find. + * @return {@code true} if the array contains any of the ints. + * @since 3.18.0 + */ + public static boolean containsAny(final int[] array, final int... objectsToFind) { + return IntStreams.of(objectsToFind).anyMatch(e -> contains(array, e)); + } + + /** + * Checks if any of the objects are in the given array. + *

+ * The method returns {@code false} if a {@code null} array is passed in. + *

+ *

+ * If the {@code array} elements you are searching implement {@link Comparator}, consider whether it is worth using + * {@link Arrays#sort(Object[], Comparator)} and {@link Arrays#binarySearch(Object[], Object)}. + *

+ * + * @param array the array to search, may be {@code null}. + * @param objectsToFind any of the objects to find, may be {@code null}. + * @return {@code true} if the array contains any of the objects. + * @since 3.13.0 + */ + public static boolean containsAny(final Object[] array, final Object... objectsToFind) { + return Streams.of(objectsToFind).anyMatch(e -> contains(array, e)); + } + + /** + * Returns a copy of the given array of size 1 greater than the argument. + * The last value of the array is left to the default value. + * + * @param array The array to copy, must not be {@code null}. + * @param newArrayComponentType If {@code array} is {@code null}, create a + * size 1 array of this type. + * @return A new copy of the array of size 1 greater than the input. + */ + private static Object copyArrayGrow1(final Object array, final Class newArrayComponentType) { + if (array != null) { + final int arrayLength = Array.getLength(array); + final Object newArray = Array.newInstance(array.getClass().getComponentType(), arrayLength + 1); + System.arraycopy(array, 0, newArray, 0, arrayLength); + return newArray; + } + return Array.newInstance(newArrayComponentType, 1); + } + + /** + * Gets the nTh element of an array or null if the index is out of bounds or the array is null. + * + * @param The type of array elements. + * @param array The array to index. + * @param index The index. + * @return the nTh element of an array or null if the index is out of bounds or the array is null. + * @since 3.11 + */ + public static T get(final T[] array, final int index) { + return get(array, index, null); + } + + /** + * Gets the nTh element of an array or a default value if the index is out of bounds. + * + * @param The type of array elements. + * @param array The array to index. + * @param index The index. + * @param defaultValue The return value of the given index is out of bounds. + * @return the nTh element of an array or a default value if the index is out of bounds. + * @since 3.11 + */ + public static T get(final T[] array, final int index, final T defaultValue) { + return isArrayIndexValid(array, index) ? array[index] : defaultValue; + } + + /** + * Gets an array's component type. + * + * @param The array type. + * @param array The array. + * @return The component type. + * @since 3.13.0 + */ + public static Class getComponentType(final T[] array) { + return ClassUtils.getComponentType(ObjectUtils.getClass(array)); + } + + /** + * Gets the number of dimensions of an array. + *

+ * The JVM specification limits the number of dimensions to 255. + *

+ * + * @param array the array, may be {@code null}. + * @return The number of dimensions, 0 if the input is null or not an array. The JVM specification limits the number of dimensions to 255. + * @since 3.21.0 + * @see JVM specification Field Descriptors + */ + public static int getDimensions(final Object array) { + int dimensions = 0; + if (array != null) { + Class arrayClass = array.getClass(); + while (arrayClass.isArray()) { + dimensions++; + arrayClass = arrayClass.getComponentType(); + } + } + return dimensions; + } + + /** + * Gets the length of the specified array. + * This method handles {@link Object} arrays and primitive arrays. + *

+ * If the input array is {@code null}, {@code 0} is returned. + *

+ *
+     * ArrayUtils.getLength(null)            = 0
+     * ArrayUtils.getLength([])              = 0
+     * ArrayUtils.getLength([null])          = 1
+     * ArrayUtils.getLength([true, false])   = 2
+     * ArrayUtils.getLength([1, 2, 3])       = 3
+     * ArrayUtils.getLength(["a", "b", "c"]) = 3
+     * 
+ * + * @param array the array to retrieve the length from, may be {@code null}. + * @return The length of the array, or {@code 0} if the array is {@code null}. + * @throws IllegalArgumentException if the object argument is not an array. + * @since 2.1 + */ + public static int getLength(final Object array) { + return array != null ? Array.getLength(array) : 0; + } + + /** + * Gets a hash code for an array handling multidimensional arrays. + *

+ * Multi-dimensional primitive arrays are also handled by this method. + *

+ * + * @param array the array to get a hash code for, may be {@code null}. + * @return a hash code for the array. + * @see HashCodeBuilder + */ + public static int hashCode(final Object array) { + return new HashCodeBuilder().append(array).toHashCode(); + } + + static void increment(final Map occurrences, final K boxed) { + occurrences.computeIfAbsent(boxed, k -> new MutableInt()).increment(); + } + + /** + * Finds the indices of the given value in the array. + *

+ * This method returns an empty BitSet for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final boolean[] array, final boolean valueToFind) { + return indexesOf(array, valueToFind, 0); + } + + /** + * Finds the indices of the given value in the array starting at the given index. + *

+ * This method returns an empty BitSet for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return an empty BitSet ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return a BitSet of all the indices of the value within the array, an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final boolean[] array, final boolean valueToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given value in the array. + * + *

+ * This method returns an empty BitSet for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return a BitSet of all the indices of the value within the array, an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final byte[] array, final byte valueToFind) { + return indexesOf(array, valueToFind, 0); + } + + /** + * Finds the indices of the given value in the array starting at the given index. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return an empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final byte[] array, final byte valueToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given value in the array. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final char[] array, final char valueToFind) { + return indexesOf(array, valueToFind, 0); + } + + /** + * Finds the indices of the given value in the array starting at the given index. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return an empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final char[] array, final char valueToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given value in the array. + * + *

This method returns empty BitSet for a {@code null} input array.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final double[] array, final double valueToFind) { + return indexesOf(array, valueToFind, 0); + } + + /** + * Finds the indices of the given value within a given tolerance in the array. + * + *

+ * This method will return all the indices of the value which fall between the region + * defined by valueToFind - tolerance and valueToFind + tolerance, each time between the nearest integers. + *

+ * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param tolerance tolerance of the search. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final double[] array, final double valueToFind, final double tolerance) { + return indexesOf(array, valueToFind, 0, tolerance); + } + + /** + * Finds the indices of the given value in the array starting at the given index. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return an empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return a BitSet of the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final double[] array, final double valueToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given value in the array starting at the given index. + * + *

+ * This method will return the indices of the values which fall between the region + * defined by valueToFind - tolerance and valueToFind + tolerance, between the nearest integers. + *

+ * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return an empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @param tolerance tolerance of the search. + * @return a BitSet of the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final double[] array, final double valueToFind, int startIndex, final double tolerance) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex, tolerance); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given value in the array. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final float[] array, final float valueToFind) { + return indexesOf(array, valueToFind, 0); + } + + /** + * Finds the indices of the given value in the array starting at the given index. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final float[] array, final float valueToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given value in the array. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final int[] array, final int valueToFind) { + return indexesOf(array, valueToFind, 0); + } + + /** + * Finds the indices of the given value in the array starting at the given index. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return an empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final int[] array, final int valueToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given value in the array. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final long[] array, final long valueToFind) { + return indexesOf(array, valueToFind, 0); + } + + /** + * Finds the indices of the given value in the array starting at the given index. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return an empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final long[] array, final long valueToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given object in the array. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param objectToFind the object to find, may be {@code null}. + * @return a BitSet of all the indices of the object within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final Object[] array, final Object objectToFind) { + return indexesOf(array, objectToFind, 0); + } + + /** + * Finds the indices of the given object in the array starting at the given index. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return an empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param objectToFind the object to find, may be {@code null}. + * @param startIndex the index to start searching. + * @return a BitSet of all the indices of the object within the array starting at the index, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final Object[] array, final Object objectToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, objectToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the indices of the given value in the array. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final short[] array, final short valueToFind) { + return indexesOf(array, valueToFind, 0); + } + + /** + * Finds the indices of the given value in the array starting at the given index. + * + *

This method returns an empty BitSet for a {@code null} input array.

+ * + *

A negative startIndex is treated as zero. A startIndex larger than the array + * length will return an empty BitSet.

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return a BitSet of all the indices of the value within the array, + * an empty BitSet if not found or {@code null} array input. + * @since 3.10 + */ + public static BitSet indexesOf(final short[] array, final short valueToFind, int startIndex) { + final BitSet bitSet = new BitSet(); + if (array != null) { + while (startIndex < array.length) { + startIndex = indexOf(array, valueToFind, startIndex); + if (startIndex == INDEX_NOT_FOUND) { + break; + } + bitSet.set(startIndex); + ++startIndex; + } + } + return bitSet; + } + + /** + * Finds the index of the given value in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final boolean[] array, final boolean valueToFind) { + return indexOf(array, valueToFind, 0); + } + + /** + * Finds the index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final boolean[] array, final boolean valueToFind, final int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + for (int i = max0(startIndex); i < array.length; i++) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given value in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final byte[] array, final byte valueToFind) { + return indexOf(array, valueToFind, 0); + } + + /** + * Finds the index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final byte[] array, final byte valueToFind, final int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + for (int i = max0(startIndex); i < array.length; i++) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given value in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + * @since 2.1 + */ + public static int indexOf(final char[] array, final char valueToFind) { + return indexOf(array, valueToFind, 0); + } + + /** + * Finds the index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + * @since 2.1 + */ + public static int indexOf(final char[] array, final char valueToFind, final int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + for (int i = max0(startIndex); i < array.length; i++) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given value in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final double[] array, final double valueToFind) { + return indexOf(array, valueToFind, 0); + } + + /** + * Finds the index of the given value within a given tolerance in the array. This method will return the index of the first value which falls between the + * region defined by valueToFind - tolerance and valueToFind + tolerance. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param tolerance tolerance of the search. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final double[] array, final double valueToFind, final double tolerance) { + return indexOf(array, valueToFind, 0, tolerance); + } + + /** + * Finds the index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final double[] array, final double valueToFind, final int startIndex) { + if (Double.isNaN(valueToFind)) { + return indexOfNaN(array, startIndex); + } + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + for (int i = max0(startIndex); i < array.length; i++) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given value in the array starting at the given index. This method will return the index of the first value which falls between the + * region defined by valueToFind - tolerance and valueToFind + tolerance. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @param tolerance tolerance of the search. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final double[] array, final double valueToFind, final int startIndex, final double tolerance) { + if (Double.isNaN(valueToFind)) { + return indexOfNaN(array, startIndex); + } + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + final double min = valueToFind - tolerance; + final double max = valueToFind + tolerance; + for (int i = max0(startIndex); i < array.length; i++) { + if (array[i] >= min && array[i] <= max) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given value in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final float[] array, final float valueToFind) { + return indexOf(array, valueToFind, 0); + } + + /** + * Finds the index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final float[] array, final float valueToFind, final int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + final boolean searchNaN = Float.isNaN(valueToFind); + for (int i = max0(startIndex); i < array.length; i++) { + final float element = array[i]; + if (valueToFind == element || searchNaN && Float.isNaN(element)) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given value in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final int[] array, final int valueToFind) { + return indexOf(array, valueToFind, 0); + } + + /** + * Finds the index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final int[] array, final int valueToFind, final int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + for (int i = max0(startIndex); i < array.length; i++) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given value in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final long[] array, final long valueToFind) { + return indexOf(array, valueToFind, 0); + } + + /** + * Finds the index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final long[] array, final long valueToFind, final int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + for (int i = max0(startIndex); i < array.length; i++) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given object in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param objectToFind the object to find, may be {@code null}. + * @return the index of the object within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final Object[] array, final Object objectToFind) { + return indexOf(array, objectToFind, 0); + } + + /** + * Finds the index of the given object in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param objectToFind the object to find, may be {@code null}. + * @param startIndex the index to start searching. + * @return the index of the object within the array starting at the index, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final Object[] array, final Object objectToFind, int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + startIndex = max0(startIndex); + if (objectToFind == null) { + for (int i = startIndex; i < array.length; i++) { + if (array[i] == null) { + return i; + } + } + } else { + for (int i = startIndex; i < array.length; i++) { + if (objectToFind.equals(array[i])) { + return i; + } + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the given value in the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null} + * @param valueToFind the value to find. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final short[] array, final short valueToFind) { + return indexOf(array, valueToFind, 0); + } + + /** + * Finds the index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex is treated as zero. A startIndex larger than the array length will return {@link #INDEX_NOT_FOUND} ({@code -1}). + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the index to start searching. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int indexOf(final short[] array, final short valueToFind, final int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + for (int i = max0(startIndex); i < array.length; i++) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the index of the NaN value in a double array. + * @param array the array to search for NaN, may be {@code null}. + * @param startIndex the index to start searching. + * @return the index of the NaN value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + private static int indexOfNaN(final double[] array, final int startIndex) { + if (isEmpty(array)) { + return INDEX_NOT_FOUND; + } + for (int i = max0(startIndex); i < array.length; i++) { + if (Double.isNaN(array[i])) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + public static boolean[] insert(final int index, final boolean[] array, final boolean... values) { + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final boolean[] result = new boolean[array.length + values.length]; + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + public static byte[] insert(final int index, final byte[] array, final byte... values) { + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final byte[] result = new byte[array.length + values.length]; + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + public static char[] insert(final int index, final char[] array, final char... values) { + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final char[] result = new char[array.length + values.length]; + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + public static double[] insert(final int index, final double[] array, final double... values) { + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final double[] result = new double[array.length + values.length]; + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + public static float[] insert(final int index, final float[] array, final float... values) { + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final float[] result = new float[array.length + values.length]; + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + public static int[] insert(final int index, final int[] array, final int... values) { + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final int[] result = new int[array.length + values.length]; + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + public static long[] insert(final int index, final long[] array, final long... values) { + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final long[] result = new long[array.length + values.length]; + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + public static short[] insert(final int index, final short[] array, final short... values) { + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final short[] result = new short[array.length + values.length]; + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Inserts elements into an array at the given index (starting from zero). + * + *

+ * When an array is returned, it is always a new array. + *

+ * + *
+     * ArrayUtils.insert(index, null, null)      = null
+     * ArrayUtils.insert(index, array, null)     = cloned copy of 'array'
+     * ArrayUtils.insert(index, null, values)    = null
+     * 
+ * + * @param The type of elements in {@code array} and {@code values}. + * @param index the position within {@code array} to insert the new values. + * @param array the array to insert the values into, may be {@code null}. + * @param values the new values to insert, may be {@code null}. + * @return The new array or {@code null} if the given array is {@code null}. + * @throws IndexOutOfBoundsException if {@code array} is provided and either {@code index < 0} or {@code index > array.length}. + * @since 3.6 + */ + @SafeVarargs + public static T[] insert(final int index, final T[] array, final T... values) { + /* + * Note on use of @SafeVarargs: + * + * By returning null when 'array' is null, we avoid returning the vararg + * array to the caller. We also avoid relying on the type of the vararg + * array, by inspecting the component type of 'array'. + */ + if (array == null) { + return null; + } + if (isEmpty(values)) { + return clone(array); + } + if (index < 0 || index > array.length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + array.length); + } + final Class type = getComponentType(array); + final int length = array.length + values.length; + final T[] result = newInstance(type, length); + System.arraycopy(values, 0, result, index, values.length); + if (index > 0) { + System.arraycopy(array, 0, result, 0, index); + } + if (index < array.length) { + System.arraycopy(array, index, result, index + values.length, array.length - index); + } + return result; + } + + /** + * Checks if an array is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + */ + private static boolean isArrayEmpty(final Object array) { + return getLength(array) == 0; + } + + /** + * Tests whether a given array can safely be accessed at the given index. + * + *
+     * ArrayUtils.isArrayIndexValid(null, 0)       = false
+     * ArrayUtils.isArrayIndexValid([], 0)         = false
+     * ArrayUtils.isArrayIndexValid(["a"], 0)      = true
+     * 
+ * + * @param the component type of the array. + * @param array the array to inspect, may be {@code null}. + * @param index the index of the array to be inspected. + * @return Whether the given index is safely-accessible in the given array. + * @since 3.8 + */ + public static boolean isArrayIndexValid(final T[] array, final int index) { + return index >= 0 && getLength(array) > index; + } + + /** + * Tests whether an array of primitive booleans is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final boolean[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether an array of primitive bytes is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final byte[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether an array of primitive chars is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final char[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether an array of primitive doubles is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final double[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether an array of primitive floats is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final float[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether an array of primitive ints is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final int[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether an array of primitive longs is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final long[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether an array of Objects is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final Object[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether an array of primitive shorts is empty or {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is empty or {@code null}. + * @since 2.1 + */ + public static boolean isEmpty(final short[] array) { + return isArrayEmpty(array); + } + + /** + * Tests whether two arrays have equal content, using equals(), handling multidimensional arrays + * correctly. + *

+ * Multi-dimensional primitive arrays are also handled correctly by this method. + *

+ * + * @param array1 the left-hand side array to compare, may be {@code null}. + * @param array2 the right-hand side array to compare, may be {@code null}. + * @return {@code true} if the arrays are equal. + * @deprecated Replaced by {@code java.util.Objects.deepEquals(Object, Object)} and will be + * removed from future releases. + */ + @Deprecated + public static boolean isEquals(final Object array1, final Object array2) { + return new EqualsBuilder().append(array1, array2).isEquals(); + } + + /** + * Tests whether an array of primitive booleans is not empty and not {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final boolean[] array) { + return !isEmpty(array); + } + + /** + * Tests whether an array of primitive bytes is not empty and not {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final byte[] array) { + return !isEmpty(array); + } + + /** + * Tests whether an array of primitive chars is not empty and not {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final char[] array) { + return !isEmpty(array); + } + + /** + * Tests whether an array of primitive doubles is not empty and not {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final double[] array) { + return !isEmpty(array); + } + + /** + * Tests whether an array of primitive floats is not empty and not {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final float[] array) { + return !isEmpty(array); + } + + /** + * Tests whether an array of primitive ints is not empty and not {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final int[] array) { + return !isEmpty(array); + } + + /** + * Tests whether an array of primitive longs is not empty and not {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final long[] array) { + return !isEmpty(array); + } + + /** + * Tests whether an array of primitive shorts is not empty and not {@code null}. + * + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final short[] array) { + return !isEmpty(array); + } + + /** + * Tests whether an array of Objects is not empty and not {@code null}. + * + * @param the component type of the array + * @param array the array to test. + * @return {@code true} if the array is not empty and not {@code null}. + * @since 2.5 + */ + public static boolean isNotEmpty(final T[] array) { + return !isEmpty(array); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final boolean[] array1, final boolean[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final byte[] array1, final byte[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final char[] array1, final char[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final double[] array1, final double[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final float[] array1, final float[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final int[] array1, final int[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final long[] array1, final long[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + *

+ * Any multi-dimensional aspects of the arrays are ignored. + *

+ * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + * @since 3.11 + */ + public static boolean isSameLength(final Object array1, final Object array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + *

+ * Any multi-dimensional aspects of the arrays are ignored. + *

+ * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final Object[] array1, final Object[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same length, treating {@code null} arrays as length {@code 0}. + * + * @param array1 the first array, may be {@code null}. + * @param array2 the second array, may be {@code null}. + * @return {@code true} if length of arrays matches, treating {@code null} as an empty array. + */ + public static boolean isSameLength(final short[] array1, final short[] array2) { + return getLength(array1) == getLength(array2); + } + + /** + * Tests whether two arrays are the same type taking into account multidimensional arrays. + * + * @param array1 the first array, must not be {@code null}. + * @param array2 the second array, must not be {@code null}. + * @return {@code true} if type of arrays matches. + * @throws IllegalArgumentException if either array is {@code null}. + */ + public static boolean isSameType(final Object array1, final Object array2) { + if (array1 == null || array2 == null) { + throw new IllegalArgumentException("The Array must not be null"); + } + return array1.getClass().getName().equals(array2.getClass().getName()); + } + + /** + * Tests whether whether the provided array is sorted according to natural ordering ({@code false} before {@code true}). + * + * @param array the array to check. + * @return whether the array is sorted according to natural ordering. + * @since 3.4 + */ + public static boolean isSorted(final boolean[] array) { + if (getLength(array) < 2) { + return true; + } + boolean previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final boolean current = array[i]; + if (BooleanUtils.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Tests whether the provided array is sorted according to natural ordering. + * + * @param array the array to check. + * @return whether the array is sorted according to natural ordering. + * @since 3.4 + */ + public static boolean isSorted(final byte[] array) { + if (getLength(array) < 2) { + return true; + } + byte previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final byte current = array[i]; + if (Byte.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Tests whether the provided array is sorted according to natural ordering. + * + * @param array the array to check. + * @return whether the array is sorted according to natural ordering. + * @since 3.4 + */ + public static boolean isSorted(final char[] array) { + if (getLength(array) < 2) { + return true; + } + char previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final char current = array[i]; + if (CharUtils.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Tests whether the provided array is sorted according to natural ordering. + * + * @param array the array to check. + * @return whether the array is sorted according to natural ordering. + * @since 3.4 + */ + public static boolean isSorted(final double[] array) { + if (getLength(array) < 2) { + return true; + } + double previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final double current = array[i]; + if (Double.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Tests whether the provided array is sorted according to natural ordering. + * + * @param array the array to check. + * @return whether the array is sorted according to natural ordering. + * @since 3.4 + */ + public static boolean isSorted(final float[] array) { + if (getLength(array) < 2) { + return true; + } + float previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final float current = array[i]; + if (Float.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Tests whether the provided array is sorted according to natural ordering. + * + * @param array the array to check. + * @return whether the array is sorted according to natural ordering. + * @since 3.4 + */ + public static boolean isSorted(final int[] array) { + if (getLength(array) < 2) { + return true; + } + int previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final int current = array[i]; + if (Integer.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Tests whether the provided array is sorted according to natural ordering. + * + * @param array the array to check. + * @return whether the array is sorted according to natural ordering. + * @since 3.4 + */ + public static boolean isSorted(final long[] array) { + if (getLength(array) < 2) { + return true; + } + long previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final long current = array[i]; + if (Long.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Tests whether the provided array is sorted according to natural ordering. + * + * @param array the array to check. + * @return whether the array is sorted according to natural ordering. + * @since 3.4 + */ + public static boolean isSorted(final short[] array) { + if (getLength(array) < 2) { + return true; + } + short previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final short current = array[i]; + if (Short.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Tests whether the provided array is sorted according to the class's + * {@code compareTo} method. + * + * @param array the array to check. + * @param the datatype of the array to check, it must implement {@link Comparable}. + * @return whether the array is sorted. + * @since 3.4 + */ + public static > boolean isSorted(final T[] array) { + return isSorted(array, Comparable::compareTo); + } + + /** + * Tests whether the provided array is sorted according to the provided {@link Comparator}. + * + * @param array the array to check. + * @param comparator the {@link Comparator} to compare over. + * @param the datatype of the array. + * @return whether the array is sorted. + * @throws NullPointerException if {@code comparator} is {@code null}. + * @since 3.4 + */ + public static boolean isSorted(final T[] array, final Comparator comparator) { + Objects.requireNonNull(comparator, "comparator"); + if (getLength(array) < 2) { + return true; + } + T previous = array[0]; + final int n = array.length; + for (int i = 1; i < n; i++) { + final T current = array[i]; + if (comparator.compare(previous, current) > 0) { + return false; + } + previous = current; + } + return true; + } + + /** + * Finds the last index of the given value within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) if {@code null} array input. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param valueToFind the object to find. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final boolean[] array, final boolean valueToFind) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final boolean[] array, final boolean valueToFind, int startIndex) { + if (isEmpty(array) || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + for (int i = startIndex; i >= 0; i--) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given value within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param valueToFind the object to find. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final byte[] array, final byte valueToFind) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final byte[] array, final byte valueToFind, int startIndex) { + if (array == null || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + for (int i = startIndex; i >= 0; i--) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given value within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param valueToFind the object to find. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + * @since 2.1 + */ + public static int lastIndexOf(final char[] array, final char valueToFind) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + * @since 2.1 + */ + public static int lastIndexOf(final char[] array, final char valueToFind, int startIndex) { + if (array == null || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + for (int i = startIndex; i >= 0; i--) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given value within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param valueToFind the object to find. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final double[] array, final double valueToFind) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given value within a given tolerance in the array. This method will return the index of the last value which falls between + * the region defined by valueToFind - tolerance and valueToFind + tolerance. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to search for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param tolerance tolerance of the search. + * @return the index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final double[] array, final double valueToFind, final double tolerance) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE, tolerance); + } + + /** + * Finds the last index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final double[] array, final double valueToFind, int startIndex) { + if (isEmpty(array) || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + for (int i = startIndex; i >= 0; i--) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given value in the array starting at the given index. This method will return the index of the last value which falls between + * the region defined by valueToFind - tolerance and valueToFind + tolerance. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @param tolerance search for value within plus/minus this amount. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final double[] array, final double valueToFind, int startIndex, final double tolerance) { + if (isEmpty(array) || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + final double min = valueToFind - tolerance; + final double max = valueToFind + tolerance; + for (int i = startIndex; i >= 0; i--) { + if (array[i] >= min && array[i] <= max) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given value within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param valueToFind the object to find. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final float[] array, final float valueToFind) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final float[] array, final float valueToFind, int startIndex) { + if (isEmpty(array) || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + for (int i = startIndex; i >= 0; i--) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given value within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param valueToFind the object to find. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final int[] array, final int valueToFind) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final int[] array, final int valueToFind, int startIndex) { + if (array == null || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + for (int i = startIndex; i >= 0; i--) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given value within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param valueToFind the object to find. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final long[] array, final long valueToFind) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final long[] array, final long valueToFind, int startIndex) { + if (array == null || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + for (int i = startIndex; i >= 0; i--) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given object within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param objectToFind the object to find, may be {@code null}. + * @return the last index of the object within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final Object[] array, final Object objectToFind) { + return lastIndexOf(array, objectToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given object in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param objectToFind the object to find, may be {@code null}. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the object within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final Object[] array, final Object objectToFind, int startIndex) { + if (array == null || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + if (objectToFind == null) { + for (int i = startIndex; i >= 0; i--) { + if (array[i] == null) { + return i; + } + } + } else if (array.getClass().getComponentType().isInstance(objectToFind)) { + for (int i = startIndex; i >= 0; i--) { + if (objectToFind.equals(array[i])) { + return i; + } + } + } + return INDEX_NOT_FOUND; + } + + /** + * Finds the last index of the given value within the array. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ * + * @param array the array to traverse backwards looking for the object, may be {@code null}. + * @param valueToFind the object to find. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final short[] array, final short valueToFind) { + return lastIndexOf(array, valueToFind, Integer.MAX_VALUE); + } + + /** + * Finds the last index of the given value in the array starting at the given index. + *

+ * This method returns {@link #INDEX_NOT_FOUND} ({@code -1}) for a {@code null} input array. + *

+ *

+ * A negative startIndex will return {@link #INDEX_NOT_FOUND} ({@code -1}). A startIndex larger than the array length will search from the end of the array. + *

+ * + * @param array the array to traverse for looking for the object, may be {@code null}. + * @param valueToFind the value to find. + * @param startIndex the start index to traverse backwards from. + * @return the last index of the value within the array, {@link #INDEX_NOT_FOUND} ({@code -1}) if not found or {@code null} array input. + */ + public static int lastIndexOf(final short[] array, final short valueToFind, int startIndex) { + if (array == null || startIndex < 0) { + return INDEX_NOT_FOUND; + } + if (startIndex >= array.length) { + startIndex = array.length - 1; + } + for (int i = startIndex; i >= 0; i--) { + if (valueToFind == array[i]) { + return i; + } + } + return INDEX_NOT_FOUND; + } + + /** + * Maps elements from an array into elements of a new array of a given type, while mapping old elements to new elements. + * + * @param The input array type. + * @param The output array type. + * @param The type of exceptions thrown when the mapper function fails. + * @param array The input array. + * @param componentType the component type of the result array. + * @param mapper a non-interfering, stateless function to apply to each element. + * @return a new array. + * @throws E Thrown when the mapper function fails. + */ + private static R[] map(final T[] array, final Class componentType, final FailableFunction mapper) + throws E { + return ArrayFill.fill(newInstance(componentType, array.length), i -> mapper.apply(array[i])); + } + + private static int max0(final int other) { + return Math.max(0, other); + } + + /** + * Delegates to {@link Array#newInstance(Class,int)} using generics. + * + * @param The array type. + * @param componentType The array class. + * @param length the array length + * @return The new array. + * @throws NullPointerException if the specified {@code componentType} parameter is null. + * @since 3.13.0 + */ + @SuppressWarnings("unchecked") // OK, because array and values are of type T + public static T[] newInstance(final Class componentType, final int length) { + return (T[]) Array.newInstance(componentType, length); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns a default array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param The array type. + * @param array the array to check for {@code null} or empty + * @param defaultArray A default array, usually empty. + * @return the same array, or defaultArray if {@code null} or empty input. + * @since 3.15.0 + */ + public static T[] nullTo(final T[] array, final T[] defaultArray) { + return isEmpty(array) ? defaultArray : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static boolean[] nullToEmpty(final boolean[] array) { + return isEmpty(array) ? EMPTY_BOOLEAN_ARRAY : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Boolean[] nullToEmpty(final Boolean[] array) { + return nullTo(array, EMPTY_BOOLEAN_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static byte[] nullToEmpty(final byte[] array) { + return isEmpty(array) ? EMPTY_BYTE_ARRAY : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Byte[] nullToEmpty(final Byte[] array) { + return nullTo(array, EMPTY_BYTE_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static char[] nullToEmpty(final char[] array) { + return isEmpty(array) ? EMPTY_CHAR_ARRAY : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Character[] nullToEmpty(final Character[] array) { + return nullTo(array, EMPTY_CHARACTER_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 3.2 + */ + public static Class[] nullToEmpty(final Class[] array) { + return nullTo(array, EMPTY_CLASS_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static double[] nullToEmpty(final double[] array) { + return isEmpty(array) ? EMPTY_DOUBLE_ARRAY : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Double[] nullToEmpty(final Double[] array) { + return nullTo(array, EMPTY_DOUBLE_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static float[] nullToEmpty(final float[] array) { + return isEmpty(array) ? EMPTY_FLOAT_ARRAY : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Float[] nullToEmpty(final Float[] array) { + return nullTo(array, EMPTY_FLOAT_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static int[] nullToEmpty(final int[] array) { + return isEmpty(array) ? EMPTY_INT_ARRAY : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Integer[] nullToEmpty(final Integer[] array) { + return nullTo(array, EMPTY_INTEGER_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static long[] nullToEmpty(final long[] array) { + return isEmpty(array) ? EMPTY_LONG_ARRAY : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Long[] nullToEmpty(final Long[] array) { + return nullTo(array, EMPTY_LONG_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Object[] nullToEmpty(final Object[] array) { + return nullTo(array, EMPTY_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static short[] nullToEmpty(final short[] array) { + return isEmpty(array) ? EMPTY_SHORT_ARRAY : array; + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static Short[] nullToEmpty(final Short[] array) { + return nullTo(array, EMPTY_SHORT_OBJECT_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ *

+ * As a memory optimizing technique an empty array passed in will be overridden with + * the empty {@code public static} references in this class. + *

+ * + * @param array the array to check for {@code null} or empty. + * @return the same array, {@code public static} empty array if {@code null} or empty input. + * @since 2.5 + */ + public static String[] nullToEmpty(final String[] array) { + return nullTo(array, EMPTY_STRING_ARRAY); + } + + /** + * Defensive programming technique to change a {@code null} + * reference to an empty one. + *

+ * This method returns an empty array for a {@code null} input array. + *

+ * + * @param array the array to check for {@code null} or empty. + * @param type the class representation of the desired array. + * @param the class type. + * @return the same array, {@code public static} empty array if {@code null}. + * @throws IllegalArgumentException if the type argument is null. + * @since 3.5 + */ + public static T[] nullToEmpty(final T[] array, final Class type) { + if (type == null) { + throw new IllegalArgumentException("The type must not be null"); + } + if (array == null) { + return type.cast(Array.newInstance(type.getComponentType(), 0)); + } + return array; + } + + /** + * Gets the {@link ThreadLocalRandom} for {@code shuffle} methods that don't take a {@link Random} argument. + * + * @return the current ThreadLocalRandom. + */ + private static ThreadLocalRandom random() { + return ThreadLocalRandom.current(); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove([true], 0)              = []
+     * ArrayUtils.remove([true, false], 0)       = [false]
+     * ArrayUtils.remove([true, false], 1)       = [true]
+     * ArrayUtils.remove([true, true, false], 1) = [true, false]
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + public static boolean[] remove(final boolean[] array, final int index) { + return (boolean[]) remove((Object) array, index); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove([1], 0)          = []
+     * ArrayUtils.remove([1, 0], 0)       = [0]
+     * ArrayUtils.remove([1, 0], 1)       = [1]
+     * ArrayUtils.remove([1, 0, 1], 1)    = [1, 1]
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + public static byte[] remove(final byte[] array, final int index) { + return (byte[]) remove((Object) array, index); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove(['a'], 0)           = []
+     * ArrayUtils.remove(['a', 'b'], 0)      = ['b']
+     * ArrayUtils.remove(['a', 'b'], 1)      = ['a']
+     * ArrayUtils.remove(['a', 'b', 'c'], 1) = ['a', 'c']
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + public static char[] remove(final char[] array, final int index) { + return (char[]) remove((Object) array, index); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove([1.1], 0)           = []
+     * ArrayUtils.remove([2.5, 6.0], 0)      = [6.0]
+     * ArrayUtils.remove([2.5, 6.0], 1)      = [2.5]
+     * ArrayUtils.remove([2.5, 6.0, 3.8], 1) = [2.5, 3.8]
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + public static double[] remove(final double[] array, final int index) { + return (double[]) remove((Object) array, index); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove([1.1], 0)           = []
+     * ArrayUtils.remove([2.5, 6.0], 0)      = [6.0]
+     * ArrayUtils.remove([2.5, 6.0], 1)      = [2.5]
+     * ArrayUtils.remove([2.5, 6.0, 3.8], 1) = [2.5, 3.8]
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + public static float[] remove(final float[] array, final int index) { + return (float[]) remove((Object) array, index); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove([1], 0)         = []
+     * ArrayUtils.remove([2, 6], 0)      = [6]
+     * ArrayUtils.remove([2, 6], 1)      = [2]
+     * ArrayUtils.remove([2, 6, 3], 1)   = [2, 3]
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + public static int[] remove(final int[] array, final int index) { + return (int[]) remove((Object) array, index); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove([1], 0)         = []
+     * ArrayUtils.remove([2, 6], 0)      = [6]
+     * ArrayUtils.remove([2, 6], 1)      = [2]
+     * ArrayUtils.remove([2, 6, 3], 1)   = [2, 3]
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + public static long[] remove(final long[] array, final int index) { + return (long[]) remove((Object) array, index); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + private static Object remove(final Object array, final int index) { + final int length = getLength(array); + if (index < 0 || index >= length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + length); + } + final Object result = Array.newInstance(array.getClass().getComponentType(), length - 1); + System.arraycopy(array, 0, result, 0, index); + if (index < length - 1) { + System.arraycopy(array, index + 1, result, index, length - index - 1); + } + return result; + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove([1], 0)         = []
+     * ArrayUtils.remove([2, 6], 0)      = [6]
+     * ArrayUtils.remove([2, 6], 1)      = [2]
+     * ArrayUtils.remove([2, 6, 3], 1)   = [2, 3]
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + public static short[] remove(final short[] array, final int index) { + return (short[]) remove((Object) array, index); + } + + /** + * Removes the element at the specified position from the specified array. All subsequent elements are shifted to the left (subtracts one from their + * indices). + *

+ * This method returns a new array with the same elements of the input array except the element on the specified position. The component type of the + * returned array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, an IndexOutOfBoundsException will be thrown, because in that case no valid index can be specified. + *

+ * + *
+     * ArrayUtils.remove(["a"], 0)           = []
+     * ArrayUtils.remove(["a", "b"], 0)      = ["b"]
+     * ArrayUtils.remove(["a", "b"], 1)      = ["a"]
+     * ArrayUtils.remove(["a", "b", "c"], 1) = ["a", "c"]
+     * 
+ * + * @param the component type of the array. + * @param array the array to remove the element from, may not be {@code null}. + * @param index the position of the element to be removed. + * @return A new array containing the existing elements except the element at the specified position. + * @throws IndexOutOfBoundsException if the index is out of range (index < 0 || index >= array.length), or if the array is {@code null}. + * @since 2.1 + */ + @SuppressWarnings("unchecked") // remove() always creates an array of the same type as its input + public static T[] remove(final T[] array, final int index) { + return (T[]) remove((Object) array, index); + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll([true, false, true], 0, 2) = [false]
+     * ArrayUtils.removeAll([true, false, true], 1, 2) = [true]
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + public static boolean[] removeAll(final boolean[] array, final int... indices) { + return (boolean[]) removeAll((Object) array, indices); + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll([1], 0)             = []
+     * ArrayUtils.removeAll([2, 6], 0)          = [6]
+     * ArrayUtils.removeAll([2, 6], 0, 1)       = []
+     * ArrayUtils.removeAll([2, 6, 3], 1, 2)    = [2]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 2)    = [6]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 1, 2) = []
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + public static byte[] removeAll(final byte[] array, final int... indices) { + return (byte[]) removeAll((Object) array, indices); + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll([1], 0)             = []
+     * ArrayUtils.removeAll([2, 6], 0)          = [6]
+     * ArrayUtils.removeAll([2, 6], 0, 1)       = []
+     * ArrayUtils.removeAll([2, 6, 3], 1, 2)    = [2]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 2)    = [6]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 1, 2) = []
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + public static char[] removeAll(final char[] array, final int... indices) { + return (char[]) removeAll((Object) array, indices); + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll([1], 0)             = []
+     * ArrayUtils.removeAll([2, 6], 0)          = [6]
+     * ArrayUtils.removeAll([2, 6], 0, 1)       = []
+     * ArrayUtils.removeAll([2, 6, 3], 1, 2)    = [2]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 2)    = [6]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 1, 2) = []
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + public static double[] removeAll(final double[] array, final int... indices) { + return (double[]) removeAll((Object) array, indices); + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll([1], 0)             = []
+     * ArrayUtils.removeAll([2, 6], 0)          = [6]
+     * ArrayUtils.removeAll([2, 6], 0, 1)       = []
+     * ArrayUtils.removeAll([2, 6, 3], 1, 2)    = [2]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 2)    = [6]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 1, 2) = []
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + public static float[] removeAll(final float[] array, final int... indices) { + return (float[]) removeAll((Object) array, indices); + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll([1], 0)             = []
+     * ArrayUtils.removeAll([2, 6], 0)          = [6]
+     * ArrayUtils.removeAll([2, 6], 0, 1)       = []
+     * ArrayUtils.removeAll([2, 6, 3], 1, 2)    = [2]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 2)    = [6]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 1, 2) = []
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + public static int[] removeAll(final int[] array, final int... indices) { + return (int[]) removeAll((Object) array, indices); + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll([1], 0)             = []
+     * ArrayUtils.removeAll([2, 6], 0)          = [6]
+     * ArrayUtils.removeAll([2, 6], 0, 1)       = []
+     * ArrayUtils.removeAll([2, 6, 3], 1, 2)    = [2]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 2)    = [6]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 1, 2) = []
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + public static long[] removeAll(final long[] array, final int... indices) { + return (long[]) removeAll((Object) array, indices); + } + + /** + * Removes multiple array elements specified by index. + * + * @param array source + * @param indices to remove + * @return new array of same type minus elements specified by unique values of {@code indices} + */ + // package protected for access by unit tests + static Object removeAll(final Object array, final int... indices) { + if (array == null) { + return null; + } + final int length = getLength(array); + int diff = 0; // number of distinct indexes, i.e. number of entries that will be removed + final int[] clonedIndices = ArraySorter.sort(clone(indices)); + // identify length of result array + if (isNotEmpty(clonedIndices)) { + int i = clonedIndices.length; + int prevIndex = length; + while (--i >= 0) { + final int index = clonedIndices[i]; + if (index < 0 || index >= length) { + throw new IndexOutOfBoundsException("Index: " + index + ", Length: " + length); + } + if (index >= prevIndex) { + continue; + } + diff++; + prevIndex = index; + } + } + // create result array + final Object result = Array.newInstance(array.getClass().getComponentType(), length - diff); + if (diff < length && clonedIndices != null) { + int end = length; // index just after last copy + int dest = length - diff; // number of entries so far not copied + for (int i = clonedIndices.length - 1; i >= 0; i--) { + final int index = clonedIndices[i]; + if (end - index > 1) { // same as (cp > 0) + final int cp = end - index - 1; + dest -= cp; + System.arraycopy(array, index + 1, result, dest, cp); + // After this copy, we still have room for dest items. + } + end = index; + } + if (end > 0) { + System.arraycopy(array, 0, result, 0, end); + } + } + return result; + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll([1], 0)             = []
+     * ArrayUtils.removeAll([2, 6], 0)          = [6]
+     * ArrayUtils.removeAll([2, 6], 0, 1)       = []
+     * ArrayUtils.removeAll([2, 6, 3], 1, 2)    = [2]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 2)    = [6]
+     * ArrayUtils.removeAll([2, 6, 3], 0, 1, 2) = []
+     * 
+ * + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + public static short[] removeAll(final short[] array, final int... indices) { + return (short[]) removeAll((Object) array, indices); + } + + /** + * Removes the elements at the specified positions from the specified array. All remaining elements are shifted to the left. + *

+ * This method returns a new array with the same elements of the input array except those at the specified positions. The component type of the returned + * array is always the same as that of the input array. + *

+ *

+ * If the input array is {@code null}, then return {@code null}. + *

+ * + *
+     * ArrayUtils.removeAll(["a", "b", "c"], 0, 2) = ["b"]
+     * ArrayUtils.removeAll(["a", "b", "c"], 1, 2) = ["a"]
+     * 
+ * + * @param the component type of the array. + * @param array the array to remove the element from, may not be {@code null}. + * @param indices the positions of the elements to be removed. + * @return A new array containing the existing elements except those at the specified positions or {@code null} if the input array is {@code null}. + * @throws IndexOutOfBoundsException if any index is out of range (index < 0 || index >= array.length). + * @since 3.0.1 + */ + @SuppressWarnings("unchecked") // removeAll() always creates an array of the same type as its input + public static T[] removeAll(final T[] array, final int... indices) { + return (T[]) removeAll((Object) array, indices); + } + + /** + * Removes the occurrences of the specified element from the specified boolean array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(boolean[], boolean)}. + */ + @Deprecated + public static boolean[] removeAllOccurences(final boolean[] array, final boolean element) { + return (boolean[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified byte array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(byte[], byte)}. + */ + @Deprecated + public static byte[] removeAllOccurences(final byte[] array, final byte element) { + return (byte[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified char array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(char[], char)}. + */ + @Deprecated + public static char[] removeAllOccurences(final char[] array, final char element) { + return (char[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified double array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(double[], double)}. + */ + @Deprecated + public static double[] removeAllOccurences(final double[] array, final double element) { + return (double[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified float array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(float[], float)}. + */ + @Deprecated + public static float[] removeAllOccurences(final float[] array, final float element) { + return (float[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified int array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(int[], int)}. + */ + @Deprecated + public static int[] removeAllOccurences(final int[] array, final int element) { + return (int[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified long array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(long[], long)}. + */ + @Deprecated + public static long[] removeAllOccurences(final long[] array, final long element) { + return (long[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified short array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(short[], short)}. + */ + @Deprecated + public static short[] removeAllOccurences(final short[] array, final short element) { + return (short[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param the type of object in the array, may be {@code null}. + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove, may be {@code null}. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.5 + * @deprecated Use {@link #removeAllOccurrences(Object[], Object)}. + */ + @Deprecated + public static T[] removeAllOccurences(final T[] array, final T element) { + return (T[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified boolean array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static boolean[] removeAllOccurrences(final boolean[] array, final boolean element) { + return (boolean[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified byte array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static byte[] removeAllOccurrences(final byte[] array, final byte element) { + return (byte[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified char array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static char[] removeAllOccurrences(final char[] array, final char element) { + return (char[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified double array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static double[] removeAllOccurrences(final double[] array, final double element) { + return (double[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified float array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static float[] removeAllOccurrences(final float[] array, final float element) { + return (float[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified int array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static int[] removeAllOccurrences(final int[] array, final int element) { + return (int[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified long array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static long[] removeAllOccurrences(final long[] array, final long element) { + return (long[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified short array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static short[] removeAllOccurrences(final short[] array, final short element) { + return (short[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes the occurrences of the specified element from the specified array. + *

+ * All subsequent elements are shifted to the left (subtracts one from their indices). + * If the array doesn't contain such an element, no elements are removed from the array. + * {@code null} will be returned if the input array is {@code null}. + *

+ * + * @param the type of object in the array, may be {@code null}. + * @param array the input array, will not be modified, and may be {@code null}. + * @param element the element to remove, may be {@code null}. + * @return A new array containing the existing elements except the occurrences of the specified element. + * @since 3.10 + */ + public static T[] removeAllOccurrences(final T[] array, final T element) { + return (T[]) removeAt(array, indexesOf(array, element)); + } + + /** + * Removes multiple array elements specified by indices. + * + * @param array the input array, will not be modified, and may be {@code null}. + * @param indices to remove. + * @return new array of same type minus elements specified by the set bits in {@code indices}. + */ + // package protected for access by unit tests + static Object removeAt(final Object array, final BitSet indices) { + if (array == null) { + return null; + } + final int srcLength = getLength(array); + // No need to check maxIndex here, because method only currently called from removeElements() + // which guarantee to generate only valid bit entries. +// final int maxIndex = indices.length(); +// if (maxIndex > srcLength) { +// throw new IndexOutOfBoundsException("Index: " + (maxIndex-1) + ", Length: " + srcLength); +// } + final int removals = indices.cardinality(); // true bits are items to remove + final Object result = Array.newInstance(array.getClass().getComponentType(), srcLength - removals); + int srcIndex = 0; + int destIndex = 0; + int count; + int set; + while ((set = indices.nextSetBit(srcIndex)) != -1) { + count = set - srcIndex; + if (count > 0) { + System.arraycopy(array, srcIndex, result, destIndex, count); + destIndex += count; + } + srcIndex = indices.nextClearBit(set); + } + count = srcLength - srcIndex; + if (count > 0) { + System.arraycopy(array, srcIndex, result, destIndex, count); + } + return result; + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, true)                = null
+     * ArrayUtils.removeElement([], true)                  = []
+     * ArrayUtils.removeElement([true], false)             = [true]
+     * ArrayUtils.removeElement([true, false], false)      = [true]
+     * ArrayUtils.removeElement([true, false, true], true) = [false, true]
+     * 
+ * + * @param array the input array, may be {@code null}. + * @param element the element to be removed. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static boolean[] removeElement(final boolean[] array, final boolean element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, 1)        = null
+     * ArrayUtils.removeElement([], 1)          = []
+     * ArrayUtils.removeElement([1], 0)         = [1]
+     * ArrayUtils.removeElement([1, 0], 0)      = [1]
+     * ArrayUtils.removeElement([1, 0, 1], 1)   = [0, 1]
+     * 
+ * + * @param array the input array, may be {@code null}. + * @param element the element to be removed. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static byte[] removeElement(final byte[] array, final byte element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, 'a')            = null
+     * ArrayUtils.removeElement([], 'a')              = []
+     * ArrayUtils.removeElement(['a'], 'b')           = ['a']
+     * ArrayUtils.removeElement(['a', 'b'], 'a')      = ['b']
+     * ArrayUtils.removeElement(['a', 'b', 'a'], 'a') = ['b', 'a']
+     * 
+ * + * @param array the input array, may be {@code null}. + * @param element the element to be removed. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static char[] removeElement(final char[] array, final char element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, 1.1)            = null
+     * ArrayUtils.removeElement([], 1.1)              = []
+     * ArrayUtils.removeElement([1.1], 1.2)           = [1.1]
+     * ArrayUtils.removeElement([1.1, 2.3], 1.1)      = [2.3]
+     * ArrayUtils.removeElement([1.1, 2.3, 1.1], 1.1) = [2.3, 1.1]
+     * 
+ * + * @param array the input array, may be {@code null}. + * @param element the element to be removed. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static double[] removeElement(final double[] array, final double element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, 1.1)            = null
+     * ArrayUtils.removeElement([], 1.1)              = []
+     * ArrayUtils.removeElement([1.1], 1.2)           = [1.1]
+     * ArrayUtils.removeElement([1.1, 2.3], 1.1)      = [2.3]
+     * ArrayUtils.removeElement([1.1, 2.3, 1.1], 1.1) = [2.3, 1.1]
+     * 
+ * + * @param array the input array, may be {@code null}. + * @param element the element to be removed. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static float[] removeElement(final float[] array, final float element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, 1)      = null
+     * ArrayUtils.removeElement([], 1)        = []
+     * ArrayUtils.removeElement([1], 2)       = [1]
+     * ArrayUtils.removeElement([1, 3], 1)    = [3]
+     * ArrayUtils.removeElement([1, 3, 1], 1) = [3, 1]
+     * 
+ * + * @param array the input array, may be {@code null}. + * @param element the element to be removed. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static int[] removeElement(final int[] array, final int element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, 1)      = null
+     * ArrayUtils.removeElement([], 1)        = []
+     * ArrayUtils.removeElement([1], 2)       = [1]
+     * ArrayUtils.removeElement([1, 3], 1)    = [3]
+     * ArrayUtils.removeElement([1, 3, 1], 1) = [3, 1]
+     * 
+ * + * @param array the input array, may be {@code null}. + * @param element the element to be removed. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static long[] removeElement(final long[] array, final long element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, 1)      = null
+     * ArrayUtils.removeElement([], 1)        = []
+     * ArrayUtils.removeElement([1], 2)       = [1]
+     * ArrayUtils.removeElement([1, 3], 1)    = [3]
+     * ArrayUtils.removeElement([1, 3, 1], 1) = [3, 1]
+     * 
+ * + * @param array the input array, may be {@code null}. + * @param element the element to be removed. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static short[] removeElement(final short[] array, final short element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes the first occurrence of the specified element from the + * specified array. All subsequent elements are shifted to the left + * (subtracts one from their indices). If the array doesn't contain + * such an element, no elements are removed from the array. + *

+ * This method returns a new array with the same elements of the input + * array except the first occurrence of the specified element. The component + * type of the returned array is always the same as that of the input + * array. + *

+ *
+     * ArrayUtils.removeElement(null, "a")            = null
+     * ArrayUtils.removeElement([], "a")              = []
+     * ArrayUtils.removeElement(["a"], "b")           = ["a"]
+     * ArrayUtils.removeElement(["a", "b"], "a")      = ["b"]
+     * ArrayUtils.removeElement(["a", "b", "a"], "a") = ["b", "a"]
+     * 
+ * + * @param the component type of the array + * @param array the input array, may be {@code null}. + * @param element the element to be removed, may be {@code null}. + * @return A new array containing the existing elements except the first + * occurrence of the specified element. + * @since 2.1 + */ + public static T[] removeElement(final T[] array, final Object element) { + final int index = indexOf(array, element); + return index == INDEX_NOT_FOUND ? clone(array) : remove(array, index); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, true, false)               = null
+     * ArrayUtils.removeElements([], true, false)                 = []
+     * ArrayUtils.removeElements([true], false, false)            = [true]
+     * ArrayUtils.removeElements([true, false], true, true)       = [false]
+     * ArrayUtils.removeElements([true, false, true], true)       = [false, true]
+     * ArrayUtils.removeElements([true, false, true], true, true) = [false]
+     * 
+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + public static boolean[] removeElements(final boolean[] array, final boolean... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(2); // only two possible values here + for (final boolean v : values) { + increment(occurrences, Boolean.valueOf(v)); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final boolean key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + return (boolean[]) removeAt(array, toRemove); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, 1, 2)      = null
+     * ArrayUtils.removeElements([], 1, 2)        = []
+     * ArrayUtils.removeElements([1], 2, 3)       = [1]
+     * ArrayUtils.removeElements([1, 3], 1, 2)    = [3]
+     * ArrayUtils.removeElements([1, 3, 1], 1)    = [3, 1]
+     * ArrayUtils.removeElements([1, 3, 1], 1, 1) = [3]
+     * 
+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + public static byte[] removeElements(final byte[] array, final byte... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(values.length); + for (final byte v : values) { + increment(occurrences, Byte.valueOf(v)); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final byte key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + return (byte[]) removeAt(array, toRemove); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, 1, 2)      = null
+     * ArrayUtils.removeElements([], 1, 2)        = []
+     * ArrayUtils.removeElements([1], 2, 3)       = [1]
+     * ArrayUtils.removeElements([1, 3], 1, 2)    = [3]
+     * ArrayUtils.removeElements([1, 3, 1], 1)    = [3, 1]
+     * ArrayUtils.removeElements([1, 3, 1], 1, 1) = [3]
+     * 
+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + public static char[] removeElements(final char[] array, final char... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(values.length); + for (final char v : values) { + increment(occurrences, Character.valueOf(v)); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final char key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + return (char[]) removeAt(array, toRemove); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, 1, 2)      = null
+     * ArrayUtils.removeElements([], 1, 2)        = []
+     * ArrayUtils.removeElements([1], 2, 3)       = [1]
+     * ArrayUtils.removeElements([1, 3], 1, 2)    = [3]
+     * ArrayUtils.removeElements([1, 3, 1], 1)    = [3, 1]
+     * ArrayUtils.removeElements([1, 3, 1], 1, 1) = [3]
+     * 
+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + public static double[] removeElements(final double[] array, final double... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(values.length); + for (final double v : values) { + increment(occurrences, Double.valueOf(v)); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final double key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + return (double[]) removeAt(array, toRemove); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, 1, 2)      = null
+     * ArrayUtils.removeElements([], 1, 2)        = []
+     * ArrayUtils.removeElements([1], 2, 3)       = [1]
+     * ArrayUtils.removeElements([1, 3], 1, 2)    = [3]
+     * ArrayUtils.removeElements([1, 3, 1], 1)    = [3, 1]
+     * ArrayUtils.removeElements([1, 3, 1], 1, 1) = [3]
+     * 
+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + public static float[] removeElements(final float[] array, final float... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(values.length); + for (final float v : values) { + increment(occurrences, Float.valueOf(v)); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final float key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + return (float[]) removeAt(array, toRemove); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, 1, 2)      = null
+     * ArrayUtils.removeElements([], 1, 2)        = []
+     * ArrayUtils.removeElements([1], 2, 3)       = [1]
+     * ArrayUtils.removeElements([1, 3], 1, 2)    = [3]
+     * ArrayUtils.removeElements([1, 3, 1], 1)    = [3, 1]
+     * ArrayUtils.removeElements([1, 3, 1], 1, 1) = [3]
+     * 
+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + public static int[] removeElements(final int[] array, final int... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(values.length); + for (final int v : values) { + increment(occurrences, Integer.valueOf(v)); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final int key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + return (int[]) removeAt(array, toRemove); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, 1, 2)      = null
+     * ArrayUtils.removeElements([], 1, 2)        = []
+     * ArrayUtils.removeElements([1], 2, 3)       = [1]
+     * ArrayUtils.removeElements([1, 3], 1, 2)    = [3]
+     * ArrayUtils.removeElements([1, 3, 1], 1)    = [3, 1]
+     * ArrayUtils.removeElements([1, 3, 1], 1, 1) = [3]
+     * 
+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + public static long[] removeElements(final long[] array, final long... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(values.length); + for (final long v : values) { + increment(occurrences, Long.valueOf(v)); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final long key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + return (long[]) removeAt(array, toRemove); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, 1, 2)      = null
+     * ArrayUtils.removeElements([], 1, 2)        = []
+     * ArrayUtils.removeElements([1], 2, 3)       = [1]
+     * ArrayUtils.removeElements([1, 3], 1, 2)    = [3]
+     * ArrayUtils.removeElements([1, 3, 1], 1)    = [3, 1]
+     * ArrayUtils.removeElements([1, 3, 1], 1, 1) = [3]
+     * 
+ * + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + public static short[] removeElements(final short[] array, final short... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(values.length); + for (final short v : values) { + increment(occurrences, Short.valueOf(v)); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final short key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + return (short[]) removeAt(array, toRemove); + } + + /** + * Removes occurrences of specified elements, in specified quantities, + * from the specified array. All subsequent elements are shifted left. + * For any element-to-be-removed specified in greater quantities than + * contained in the original array, no change occurs beyond the + * removal of the existing matching items. + *

+ * This method returns a new array with the same elements of the input + * array except for the earliest-encountered occurrences of the specified + * elements. The component type of the returned array is always the same + * as that of the input array. + *

+ *
+     * ArrayUtils.removeElements(null, "a", "b")            = null
+     * ArrayUtils.removeElements([], "a", "b")              = []
+     * ArrayUtils.removeElements(["a"], "b", "c")           = ["a"]
+     * ArrayUtils.removeElements(["a", "b"], "a", "c")      = ["b"]
+     * ArrayUtils.removeElements(["a", "b", "a"], "a")      = ["b", "a"]
+     * ArrayUtils.removeElements(["a", "b", "a"], "a", "a") = ["b"]
+     * 
+ * + * @param the component type of the array + * @param array the input array, will not be modified, and may be {@code null}. + * @param values the values to be removed. + * @return A new array containing the existing elements except the + * earliest-encountered occurrences of the specified elements. + * @since 3.0.1 + */ + @SafeVarargs + public static T[] removeElements(final T[] array, final T... values) { + if (isEmpty(array) || isEmpty(values)) { + return clone(array); + } + final HashMap occurrences = new HashMap<>(values.length); + for (final T v : values) { + increment(occurrences, v); + } + final BitSet toRemove = new BitSet(); + for (int i = 0; i < array.length; i++) { + final T key = array[i]; + final MutableInt count = occurrences.get(key); + if (count != null) { + if (count.decrementAndGet() == 0) { + occurrences.remove(key); + } + toRemove.set(i); + } + } + @SuppressWarnings("unchecked") // removeAll() always creates an array of the same type as its input + final T[] result = (T[]) removeAt(array, toRemove); + return result; + } + + /** + * Reverses the order of the given array. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + */ + public static void reverse(final boolean[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array + * the array to reverse, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are reversed in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final boolean[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + boolean tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Reverses the order of the given array. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + */ + public static void reverse(final byte[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no change. + * @param endIndexExclusive elements up to endIndex-1 are reversed in the array. Undervalue (< start index) results in no change. Overvalue + * (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final byte[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + byte tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Reverses the order of the given array. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + */ + public static void reverse(final char[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no change. + * @param endIndexExclusive elements up to endIndex-1 are reversed in the array. Undervalue (< start index) results in no change. Overvalue + * (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final char[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + char tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Reverses the order of the given array. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null} + */ + public static void reverse(final double[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no change. + * @param endIndexExclusive elements up to endIndex-1 are reversed in the array. Undervalue (< start index) results in no change. Overvalue + * (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final double[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + double tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Reverses the order of the given array. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + */ + public static void reverse(final float[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no change. + * @param endIndexExclusive elements up to endIndex-1 are reversed in the array. Undervalue (< start index) results in no change. Overvalue + * (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final float[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + float tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Reverses the order of the given array. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + */ + public static void reverse(final int[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array + * the array to reverse, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are reversed in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final int[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + int tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Reverses the order of the given array. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + */ + public static void reverse(final long[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array + * the array to reverse, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are reversed in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final long[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + long tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Reverses the order of the given array. + *

+ * There is no special handling for multi-dimensional arrays. + *

+ *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + */ + public static void reverse(final Object[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array + * the array to reverse, may be {@code null}. + * @param startIndexInclusive + * the starting index. Under value (<0) is promoted to 0, over value (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are reversed in the array. Under value (< start index) results in no + * change. Over value (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final Object[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + Object tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Reverses the order of the given array. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array the array to reverse, may be {@code null}. + */ + public static void reverse(final short[] array) { + if (array != null) { + reverse(array, 0, array.length); + } + } + + /** + * Reverses the order of the given array in the given range. + *

+ * This method does nothing for a {@code null} input array. + *

+ * + * @param array + * the array to reverse, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are reversed in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @since 3.2 + */ + public static void reverse(final short[] array, final int startIndexInclusive, final int endIndexExclusive) { + if (array == null) { + return; + } + int i = Math.max(startIndexInclusive, 0); + int j = Math.min(array.length, endIndexExclusive) - 1; + short tmp; + while (j > i) { + tmp = array[j]; + array[j] = array[i]; + array[i] = tmp; + j--; + i++; + } + } + + /** + * Sets all elements of the specified array, using the provided generator supplier to compute each element. + *

+ * If the generator supplier throws an exception, it is relayed to the caller and the array is left in an indeterminate + * state. + *

+ * + * @param type of elements of the array, may be {@code null}. + * @param array array to be initialized, may be {@code null}. + * @param generator a function accepting an index and producing the desired value for that position. + * @return the input array + * @since 3.13.0 + */ + public static T[] setAll(final T[] array, final IntFunction generator) { + if (array != null && generator != null) { + Arrays.setAll(array, generator); + } + return array; + } + + /** + * Sets all elements of the specified array, using the provided generator supplier to compute each element. + *

+ * If the generator supplier throws an exception, it is relayed to the caller and the array is left in an indeterminate + * state. + *

+ * + * @param type of elements of the array, may be {@code null}. + * @param array array to be initialized, may be {@code null}. + * @param generator a function accepting an index and producing the desired value for that position. + * @return the input array + * @since 3.13.0 + */ + public static T[] setAll(final T[] array, final Supplier generator) { + if (array != null && generator != null) { + for (int i = 0; i < array.length; i++) { + array[i] = generator.get(); + } + } + return array; + } + + /** + * Shifts the order of the given boolean array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final boolean[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given boolean array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final boolean[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shifts the order of the given byte array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final byte[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given byte array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final byte[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shifts the order of the given char array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final char[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given char array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final char[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shifts the order of the given double array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final double[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given double array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final double[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shifts the order of the given float array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final float[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given float array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final float[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shifts the order of the given int array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final int[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given int array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final int[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shifts the order of the given long array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final long[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given long array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final long[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shifts the order of the given array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final Object[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final Object[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shifts the order of the given short array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array the array to shift, may be {@code null}. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final short[] array, final int offset) { + if (array != null) { + shift(array, 0, array.length, offset); + } + } + + /** + * Shifts the order of a series of elements in the given short array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for {@code null} or empty input arrays.

+ * + * @param array + * the array to shift, may be {@code null}. + * @param startIndexInclusive + * the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in no + * change. + * @param endIndexExclusive + * elements up to endIndex-1 are shifted in the array. Undervalue (< start index) results in no + * change. Overvalue (>array.length) is demoted to array length. + * @param offset + * The number of positions to rotate the elements. If the offset is larger than the number of elements to + * rotate, than the effective offset is modulo the number of elements to rotate. + * @since 3.5 + */ + public static void shift(final short[] array, int startIndexInclusive, int endIndexExclusive, int offset) { + if (array == null || startIndexInclusive >= array.length - 1 || endIndexExclusive <= 0) { + return; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = Math.min(endIndexExclusive, array.length); + int n = endIndexExclusive - startIndexInclusive; + if (n <= 1) { + return; + } + offset %= n; + if (offset < 0) { + offset += n; + } + // For algorithm explanations and proof of O(n) time complexity and O(1) space complexity + // see https://beradrian.wordpress.com/2015/04/07/shift-an-array-in-on-in-place/ + while (n > 1 && offset > 0) { + final int nOffset = n - offset; + if (offset > nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + n - nOffset, nOffset); + n = offset; + offset -= nOffset; + } else if (offset < nOffset) { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + startIndexInclusive += offset; + n = nOffset; + } else { + swap(array, startIndexInclusive, startIndexInclusive + nOffset, offset); + break; + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final boolean[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final boolean[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final byte[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final byte[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final char[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final char[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final double[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final double[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final float[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final float[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final int[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final int[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final long[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final long[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final Object[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final Object[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + *

+ * This method uses the current {@link ThreadLocalRandom} as its random number generator. + *

+ *

+ * Instances of {@link ThreadLocalRandom} are not cryptographically secure. For security-sensitive applications, consider using a {@code shuffle} method + * with a {@link SecureRandom} argument. + *

+ * + * @param array the array to shuffle. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final short[] array) { + shuffle(array, random()); + } + + /** + * Shuffles randomly the elements of the specified array using the Fisher-Yates shuffle + * algorithm. + * + * @param array the array to shuffle, no-op if {@code null}. + * @param random the source of randomness used to permute the elements, no-op if {@code null}. + * @see Fisher-Yates shuffle algorithm + * @since 3.6 + */ + public static void shuffle(final short[] array, final Random random) { + if (array != null && random != null) { + for (int i = array.length; i > 1; i--) { + swap(array, i - 1, random.nextInt(i), 1); + } + } + } + + /** + * Tests whether the given data array starts with an expected array, for example, signature bytes. + *

+ * If both arrays are null, the method returns true. The method return false when one array is null and the other not. + *

+ * + * @param data The data to search, maybe larger than the expected data. + * @param expected The expected data to find. + * @return whether a match was found. + * @since 3.18.0 + */ + public static boolean startsWith(final byte[] data, final byte[] expected) { + if (data == expected) { + return true; + } + if (data == null || expected == null) { + return false; + } + final int dataLen = data.length; + if (expected.length > dataLen) { + return false; + } + if (expected.length == dataLen) { + // delegate to Arrays.equals() which has optimizations on Java > 8 + return Arrays.equals(data, expected); + } + // Once we are on Java 9+ we can delegate to Arrays here as well (or not). + for (int i = 0; i < expected.length; i++) { + if (data[i] != expected[i]) { + return false; + } + } + return true; + } + + /** + * Produces a new {@code boolean} array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ * + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(boolean[], int, int) + */ + public static boolean[] subarray(final boolean[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + if (newSize <= 0) { + return EMPTY_BOOLEAN_ARRAY; + } + return arraycopy(array, startIndexInclusive, 0, newSize, boolean[]::new); + } + + /** + * Produces a new {@code byte} array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ * + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(byte[], int, int) + */ + public static byte[] subarray(final byte[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + if (newSize <= 0) { + return EMPTY_BYTE_ARRAY; + } + return arraycopy(array, startIndexInclusive, 0, newSize, byte[]::new); + } + + /** + * Produces a new {@code char} array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ * + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(char[], int, int) + */ + public static char[] subarray(final char[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + if (newSize <= 0) { + return EMPTY_CHAR_ARRAY; + } + return arraycopy(array, startIndexInclusive, 0, newSize, char[]::new); + } + + /** + * Produces a new {@code double} array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ * + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(double[], int, int) + */ + public static double[] subarray(final double[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + if (newSize <= 0) { + return EMPTY_DOUBLE_ARRAY; + } + return arraycopy(array, startIndexInclusive, 0, newSize, double[]::new); + } + + /** + * Produces a new {@code float} array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ * + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(float[], int, int) + */ + public static float[] subarray(final float[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + if (newSize <= 0) { + return EMPTY_FLOAT_ARRAY; + } + return arraycopy(array, startIndexInclusive, 0, newSize, float[]::new); + } + + /** + * Produces a new {@code int} array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ * + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(int[], int, int) + */ + public static int[] subarray(final int[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + if (newSize <= 0) { + return EMPTY_INT_ARRAY; + } + return arraycopy(array, startIndexInclusive, 0, newSize, int[]::new); + } + + /** + * Produces a new {@code long} array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ * + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(long[], int, int) + */ + public static long[] subarray(final long[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + if (newSize <= 0) { + return EMPTY_LONG_ARRAY; + } + return arraycopy(array, startIndexInclusive, 0, newSize, long[]::new); + } + + /** + * Produces a new {@code short} array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ * + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(short[], int, int) + */ + public static short[] subarray(final short[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + if (newSize <= 0) { + return EMPTY_SHORT_ARRAY; + } + return arraycopy(array, startIndexInclusive, 0, newSize, short[]::new); + } + + /** + * Produces a new array containing the elements between the start and end indices. + *

+ * The start index is inclusive, the end index exclusive. Null array input produces null output. + *

+ *

+ * The component type of the subarray is always the same as that of the input array. Thus, if the input is an array of type {@link Date}, the following + * usage is envisaged: + *

+ * + *
+     *
+     * Date[] someDates = (Date[]) ArrayUtils.subarray(allDates, 2, 5);
+     * 
+ * + * @param the component type of the array. + * @param array the input array. + * @param startIndexInclusive the starting index. Undervalue (<0) is promoted to 0, overvalue (>array.length) results in an empty array. + * @param endIndexExclusive elements up to endIndex-1 are present in the returned subarray. Undervalue (< startIndex) produces empty array, overvalue + * (>array.length) is demoted to array length. + * @return a new array containing the elements between the start and end indices. + * @since 2.1 + * @see Arrays#copyOfRange(Object[], int, int) + */ + public static T[] subarray(final T[] array, int startIndexInclusive, int endIndexExclusive) { + if (array == null) { + return null; + } + startIndexInclusive = max0(startIndexInclusive); + endIndexExclusive = max0(Math.min(endIndexExclusive, array.length)); + final int newSize = endIndexExclusive - startIndexInclusive; + final Class type = getComponentType(array); + if (newSize <= 0) { + return newInstance(type, 0); + } + return arraycopy(array, startIndexInclusive, 0, newSize, () -> newInstance(type, newSize)); + } + + /** + * Swaps two elements in the given boolean array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3], 0, 2) -> [3, 2, 1]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 0) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 1, 0) -> [2, 1, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 5) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], -1, 1) -> [2, 1, 3]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final boolean[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given boolean array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([true, false, true, false], 0, 2, 1) -> [true, false, true, false]
  • + *
  • ArrayUtils.swap([true, false, true, false], 0, 0, 1) -> [true, false, true, false]
  • + *
  • ArrayUtils.swap([true, false, true, false], 0, 2, 2) -> [true, false, true, false]
  • + *
  • ArrayUtils.swap([true, false, true, false], -3, 2, 2) -> [true, false, true, false]
  • + *
  • ArrayUtils.swap([true, false, true, false], 0, 3, 3) -> [false, false, true, true]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final boolean[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final boolean aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + } + + /** + * Swaps two elements in the given byte array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3], 0, 2) -> [3, 2, 1]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 0) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 1, 0) -> [2, 1, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 5) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], -1, 1) -> [2, 1, 3]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final byte[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given byte array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 2, 1) -> [3, 2, 1, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 0, 1) -> [1, 2, 3, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 2, 0, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], -3, 2, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 3, 3) -> [4, 2, 3, 1]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final byte[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final byte aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + } + + /** + * Swaps two elements in the given char array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3], 0, 2) -> [3, 2, 1]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 0) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 1, 0) -> [2, 1, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 5) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], -1, 1) -> [2, 1, 3]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final char[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given char array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 2, 1) -> [3, 2, 1, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 0, 1) -> [1, 2, 3, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 2, 0, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], -3, 2, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 3, 3) -> [4, 2, 3, 1]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final char[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final char aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + } + + /** + * Swaps two elements in the given double array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3], 0, 2) -> [3, 2, 1]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 0) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 1, 0) -> [2, 1, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 5) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], -1, 1) -> [2, 1, 3]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final double[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given double array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 2, 1) -> [3, 2, 1, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 0, 1) -> [1, 2, 3, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 2, 0, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], -3, 2, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 3, 3) -> [4, 2, 3, 1]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final double[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final double aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + } + + /** + * Swaps two elements in the given float array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3], 0, 2) -> [3, 2, 1]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 0) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 1, 0) -> [2, 1, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 5) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], -1, 1) -> [2, 1, 3]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final float[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given float array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 2, 1) -> [3, 2, 1, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 0, 1) -> [1, 2, 3, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 2, 0, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], -3, 2, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 3, 3) -> [4, 2, 3, 1]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final float[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final float aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + + } + + /** + * Swaps two elements in the given int array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3], 0, 2) -> [3, 2, 1]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 0) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 1, 0) -> [2, 1, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 5) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], -1, 1) -> [2, 1, 3]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final int[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given int array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 2, 1) -> [3, 2, 1, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 0, 1) -> [1, 2, 3, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 2, 0, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], -3, 2, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 3, 3) -> [4, 2, 3, 1]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final int[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final int aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + } + + /** + * Swaps two elements in the given long array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([true, false, true], 0, 2) -> [true, false, true]
  • + *
  • ArrayUtils.swap([true, false, true], 0, 0) -> [true, false, true]
  • + *
  • ArrayUtils.swap([true, false, true], 1, 0) -> [false, true, true]
  • + *
  • ArrayUtils.swap([true, false, true], 0, 5) -> [true, false, true]
  • + *
  • ArrayUtils.swap([true, false, true], -1, 1) -> [false, true, true]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final long[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given long array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 2, 1) -> [3, 2, 1, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 0, 1) -> [1, 2, 3, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 2, 0, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], -3, 2, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 3, 3) -> [4, 2, 3, 1]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final long[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final long aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + } + + /** + * Swaps two elements in the given array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap(["1", "2", "3"], 0, 2) -> ["3", "2", "1"]
  • + *
  • ArrayUtils.swap(["1", "2", "3"], 0, 0) -> ["1", "2", "3"]
  • + *
  • ArrayUtils.swap(["1", "2", "3"], 1, 0) -> ["2", "1", "3"]
  • + *
  • ArrayUtils.swap(["1", "2", "3"], 0, 5) -> ["1", "2", "3"]
  • + *
  • ArrayUtils.swap(["1", "2", "3"], -1, 1) -> ["2", "1", "3"]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final Object[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap(["1", "2", "3", "4"], 0, 2, 1) -> ["3", "2", "1", "4"]
  • + *
  • ArrayUtils.swap(["1", "2", "3", "4"], 0, 0, 1) -> ["1", "2", "3", "4"]
  • + *
  • ArrayUtils.swap(["1", "2", "3", "4"], 2, 0, 2) -> ["3", "4", "1", "2"]
  • + *
  • ArrayUtils.swap(["1", "2", "3", "4"], -3, 2, 2) -> ["3", "4", "1", "2"]
  • + *
  • ArrayUtils.swap(["1", "2", "3", "4"], 0, 3, 3) -> ["4", "2", "3", "1"]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final Object[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final Object aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + } + + /** + * Swaps two elements in the given short array. + * + *

There is no special handling for multi-dimensional arrays. This method + * does nothing for a {@code null} or empty input array or for overflow indices. + * Negative indices are promoted to 0(zero).

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3], 0, 2) -> [3, 2, 1]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 0) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 1, 0) -> [2, 1, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], 0, 5) -> [1, 2, 3]
  • + *
  • ArrayUtils.swap([1, 2, 3], -1, 1) -> [2, 1, 3]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element to swap. + * @param offset2 the index of the second element to swap. + * @since 3.5 + */ + public static void swap(final short[] array, final int offset1, final int offset2) { + swap(array, offset1, offset2, 1); + } + + /** + * Swaps a series of elements in the given short array. + * + *

This method does nothing for a {@code null} or empty input array or + * for overflow indices. Negative indices are promoted to 0(zero). If any + * of the sub-arrays to swap falls outside of the given array, then the + * swap is stopped at the end of the array and as many as possible elements + * are swapped.

+ * + * Examples: + *
    + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 2, 1) -> [3, 2, 1, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 0, 1) -> [1, 2, 3, 4]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 2, 0, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], -3, 2, 2) -> [3, 4, 1, 2]
  • + *
  • ArrayUtils.swap([1, 2, 3, 4], 0, 3, 3) -> [4, 2, 3, 1]
  • + *
+ * + * @param array the array to swap, may be {@code null}. + * @param offset1 the index of the first element in the series to swap. + * @param offset2 the index of the second element in the series to swap. + * @param len the number of elements to swap starting with the given indices. + * @since 3.5 + */ + public static void swap(final short[] array, int offset1, int offset2, int len) { + if (isEmpty(array) || offset1 >= array.length || offset2 >= array.length) { + return; + } + offset1 = max0(offset1); + offset2 = max0(offset2); + if (offset1 == offset2) { + return; + } + len = Math.min(Math.min(len, array.length - offset1), array.length - offset2); + for (int i = 0; i < len; i++, offset1++, offset2++) { + final short aux = array[offset1]; + array[offset1] = array[offset2]; + array[offset2] = aux; + } + } + + /** + * Create a type-safe generic array. + *

+ * The Java language does not allow an array to be created from a generic type: + *

+ *
+    public static <T> T[] createAnArray(int size) {
+        return new T[size]; // compiler error here
+    }
+    public static <T> T[] createAnArray(int size) {
+        return (T[]) new Object[size]; // ClassCastException at runtime
+    }
+     * 
+ *

+ * Therefore new arrays of generic types can be created with this method. + * For example, an array of Strings can be created: + *

+ *
{@code
+     * String[] array = ArrayUtils.toArray("1", "2");
+     * String[] emptyArray = ArrayUtils.toArray();
+     * }
+ *

+ * The method is typically used in scenarios, where the caller itself uses generic types + * that have to be combined into an array. + *

+ *

+ * Note, this method makes only sense to provide arguments of the same type so that the + * compiler can deduce the type of the array itself. While it is possible to select the + * type explicitly like in + * {@code Number[] array = ArrayUtils.toArray(Integer.valueOf(42), Double.valueOf(Math.PI))}, + * there is no real advantage when compared to + * {@code new Number[] {Integer.valueOf(42), Double.valueOf(Math.PI)}}. + *

+ * + * @param the array's element type. + * @param items the varargs array items, null allowed. + * @return the array, not null unless a null array is passed in. + * @since 3.0 + */ + public static T[] toArray(@SuppressWarnings("unchecked") final T... items) { + return items; + } + + /** + * Converts the given array into a {@link java.util.Map}. Each element of the array must be either a {@link java.util.Map.Entry} or an Array, containing at + * least two elements, where the first element is used as key and the second as value. + *

+ * This method can be used to initialize: + *

+ * + *
+     *
+     * // Create a Map mapping colors.
+     * Map colorMap = ArrayUtils.toMap(new String[][] { { "RED", "#FF0000" }, { "GREEN", "#00FF00" }, { "BLUE", "#0000FF" } });
+     * 
+ *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array an array whose elements are either a {@link java.util.Map.Entry} or an Array containing at least two elements, may be {@code null}. + * @return a {@link Map} that was created from the array. + * @throws IllegalArgumentException if one element of this Array is itself an Array containing less than two elements. + * @throws IllegalArgumentException if the array contains elements other than {@link java.util.Map.Entry} and an Array. + */ + public static Map toMap(final Object[] array) { + if (array == null) { + return null; + } + final Map map = new HashMap<>((int) (array.length * 1.5)); + for (int i = 0; i < array.length; i++) { + final Object object = array[i]; + if (object instanceof Map.Entry) { + final Map.Entry entry = (Map.Entry) object; + map.put(entry.getKey(), entry.getValue()); + } else if (object instanceof Object[]) { + final Object[] entry = (Object[]) object; + if (entry.length < 2) { + throw new IllegalArgumentException("Array element " + i + ", '" + + object + + "', has a length less than 2"); + } + map.put(entry[0], entry[1]); + } else { + throw new IllegalArgumentException("Array element " + i + ", '" + + object + + "', is neither of type Map.Entry nor an Array"); + } + } + return map; + } + + /** + * Converts an array of primitive booleans to objects. + * + *

This method returns {@code null} for a {@code null} input array.

+ * + * @param array a {@code boolean} array. + * @return a {@link Boolean} array, {@code null} if null array input. + */ + public static Boolean[] toObject(final boolean[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_BOOLEAN_OBJECT_ARRAY; + } + return setAll(new Boolean[array.length], i -> array[i] ? Boolean.TRUE : Boolean.FALSE); + } + + /** + * Converts an array of primitive bytes to objects. + * + *

This method returns {@code null} for a {@code null} input array.

+ * + * @param array a {@code byte} array. + * @return a {@link Byte} array, {@code null} if null array input. + */ + public static Byte[] toObject(final byte[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_BYTE_OBJECT_ARRAY; + } + return setAll(new Byte[array.length], i -> Byte.valueOf(array[i])); + } + + /** + * Converts an array of primitive chars to objects. + * + *

This method returns {@code null} for a {@code null} input array.

+ * + * @param array a {@code char} array. + * @return a {@link Character} array, {@code null} if null array input. + */ + public static Character[] toObject(final char[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_CHARACTER_OBJECT_ARRAY; + } + return setAll(new Character[array.length], i -> Character.valueOf(array[i])); + } + + /** + * Converts an array of primitive doubles to objects. + * + *

This method returns {@code null} for a {@code null} input array.

+ * + * @param array a {@code double} array. + * @return a {@link Double} array, {@code null} if null array input. + */ + public static Double[] toObject(final double[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_DOUBLE_OBJECT_ARRAY; + } + return setAll(new Double[array.length], i -> Double.valueOf(array[i])); + } + + /** + * Converts an array of primitive floats to objects. + * + *

This method returns {@code null} for a {@code null} input array.

+ * + * @param array a {@code float} array. + * @return a {@link Float} array, {@code null} if null array input. + */ + public static Float[] toObject(final float[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_FLOAT_OBJECT_ARRAY; + } + return setAll(new Float[array.length], i -> Float.valueOf(array[i])); + } + + /** + * Converts an array of primitive ints to objects. + * + *

This method returns {@code null} for a {@code null} input array.

+ * + * @param array an {@code int} array. + * @return an {@link Integer} array, {@code null} if null array input. + */ + public static Integer[] toObject(final int[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_INTEGER_OBJECT_ARRAY; + } + return setAll(new Integer[array.length], i -> Integer.valueOf(array[i])); + } + + /** + * Converts an array of primitive longs to objects. + * + *

This method returns {@code null} for a {@code null} input array.

+ * + * @param array a {@code long} array. + * @return a {@link Long} array, {@code null} if null array input. + */ + public static Long[] toObject(final long[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_LONG_OBJECT_ARRAY; + } + return setAll(new Long[array.length], i -> Long.valueOf(array[i])); + } + + /** + * Converts an array of primitive shorts to objects. + * + *

This method returns {@code null} for a {@code null} input array.

+ * + * @param array a {@code short} array. + * @return a {@link Short} array, {@code null} if null array input. + */ + public static Short[] toObject(final short[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_SHORT_OBJECT_ARRAY; + } + return setAll(new Short[array.length], i -> Short.valueOf(array[i])); + } + + /** + * Converts an array of object Booleans to primitives. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ *

+ * Null array elements map to false, like {@code Boolean.parseBoolean(null)} and its callers return false. + *

+ * + * @param array a {@link Boolean} array, may be {@code null}. + * @return a {@code boolean} array, {@code null} if null array input. + */ + public static boolean[] toPrimitive(final Boolean[] array) { + return toPrimitive(array, false); + } + + /** + * Converts an array of object Booleans to primitives handling {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Boolean} array, may be {@code null}. + * @param valueForNull the value to insert if {@code null} found. + * @return a {@code boolean} array, {@code null} if null array input. + */ + public static boolean[] toPrimitive(final Boolean[] array, final boolean valueForNull) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_BOOLEAN_ARRAY; + } + final boolean[] result = new boolean[array.length]; + for (int i = 0; i < array.length; i++) { + final Boolean b = array[i]; + result[i] = b == null ? valueForNull : b.booleanValue(); + } + return result; + } + + /** + * Converts an array of object Bytes to primitives. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Byte} array, may be {@code null}. + * @return a {@code byte} array, {@code null} if null array input. + * @throws NullPointerException if an array element is {@code null}. + */ + public static byte[] toPrimitive(final Byte[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_BYTE_ARRAY; + } + final byte[] result = new byte[array.length]; + for (int i = 0; i < array.length; i++) { + result[i] = array[i].byteValue(); + } + return result; + } + + /** + * Converts an array of object Bytes to primitives handling {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Byte} array, may be {@code null}. + * @param valueForNull the value to insert if {@code null} found. + * @return a {@code byte} array, {@code null} if null array input. + */ + public static byte[] toPrimitive(final Byte[] array, final byte valueForNull) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_BYTE_ARRAY; + } + final byte[] result = new byte[array.length]; + for (int i = 0; i < array.length; i++) { + final Byte b = array[i]; + result[i] = b == null ? valueForNull : b.byteValue(); + } + return result; + } + + /** + * Converts an array of object Characters to primitives. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Character} array, may be {@code null}. + * @return a {@code char} array, {@code null} if null array input. + * @throws NullPointerException if an array element is {@code null}. + */ + public static char[] toPrimitive(final Character[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_CHAR_ARRAY; + } + final char[] result = new char[array.length]; + for (int i = 0; i < array.length; i++) { + result[i] = array[i].charValue(); + } + return result; + } + + /** + * Converts an array of object Character to primitives handling {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Character} array, may be {@code null}. + * @param valueForNull the value to insert if {@code null} found. + * @return a {@code char} array, {@code null} if null array input. + */ + public static char[] toPrimitive(final Character[] array, final char valueForNull) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_CHAR_ARRAY; + } + final char[] result = new char[array.length]; + for (int i = 0; i < array.length; i++) { + final Character b = array[i]; + result[i] = b == null ? valueForNull : b.charValue(); + } + return result; + } + + /** + * Converts an array of object Doubles to primitives. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Double} array, may be {@code null}. + * @return a {@code double} array, {@code null} if null array input. + * @throws NullPointerException if an array element is {@code null}. + */ + public static double[] toPrimitive(final Double[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_DOUBLE_ARRAY; + } + final double[] result = new double[array.length]; + for (int i = 0; i < array.length; i++) { + result[i] = array[i].doubleValue(); + } + return result; + } + + /** + * Converts an array of object Doubles to primitives handling {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Double} array, may be {@code null}. + * @param valueForNull the value to insert if {@code null} found. + * @return a {@code double} array, {@code null} if null array input. + */ + public static double[] toPrimitive(final Double[] array, final double valueForNull) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_DOUBLE_ARRAY; + } + final double[] result = new double[array.length]; + for (int i = 0; i < array.length; i++) { + final Double b = array[i]; + result[i] = b == null ? valueForNull : b.doubleValue(); + } + return result; + } + + /** + * Converts an array of object Floats to primitives. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Float} array, may be {@code null}. + * @return a {@code float} array, {@code null} if null array input. + * @throws NullPointerException if an array element is {@code null}. + */ + public static float[] toPrimitive(final Float[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_FLOAT_ARRAY; + } + final float[] result = new float[array.length]; + for (int i = 0; i < array.length; i++) { + result[i] = array[i].floatValue(); + } + return result; + } + + /** + * Converts an array of object Floats to primitives handling {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Float} array, may be {@code null}. + * @param valueForNull the value to insert if {@code null} found. + * @return a {@code float} array, {@code null} if null array input. + */ + public static float[] toPrimitive(final Float[] array, final float valueForNull) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_FLOAT_ARRAY; + } + final float[] result = new float[array.length]; + for (int i = 0; i < array.length; i++) { + final Float b = array[i]; + result[i] = b == null ? valueForNull : b.floatValue(); + } + return result; + } + + /** + * Converts an array of object Integers to primitives. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Integer} array, may be {@code null}. + * @return an {@code int} array, {@code null} if null array input. + * @throws NullPointerException if an array element is {@code null}. + */ + public static int[] toPrimitive(final Integer[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_INT_ARRAY; + } + final int[] result = new int[array.length]; + for (int i = 0; i < array.length; i++) { + result[i] = array[i].intValue(); + } + return result; + } + + /** + * Converts an array of object Integer to primitives handling {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Integer} array, may be {@code null}. + * @param valueForNull the value to insert if {@code null} found. + * @return an {@code int} array, {@code null} if null array input. + */ + public static int[] toPrimitive(final Integer[] array, final int valueForNull) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_INT_ARRAY; + } + final int[] result = new int[array.length]; + for (int i = 0; i < array.length; i++) { + final Integer b = array[i]; + result[i] = b == null ? valueForNull : b.intValue(); + } + return result; + } + + /** + * Converts an array of object Longs to primitives. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Long} array, may be {@code null}. + * @return a {@code long} array, {@code null} if null array input. + * @throws NullPointerException if an array element is {@code null}. + */ + public static long[] toPrimitive(final Long[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_LONG_ARRAY; + } + final long[] result = new long[array.length]; + for (int i = 0; i < array.length; i++) { + result[i] = array[i].longValue(); + } + return result; + } + + /** + * Converts an array of object Long to primitives handling {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Long} array, may be {@code null}. + * @param valueForNull the value to insert if {@code null} found. + * @return a {@code long} array, {@code null} if null array input. + */ + public static long[] toPrimitive(final Long[] array, final long valueForNull) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_LONG_ARRAY; + } + final long[] result = new long[array.length]; + for (int i = 0; i < array.length; i++) { + final Long b = array[i]; + result[i] = b == null ? valueForNull : b.longValue(); + } + return result; + } + + /** + * Create an array of primitive type from an array of wrapper types. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array an array of wrapper object. + * @return an array of the corresponding primitive type, or the original array. + * @since 3.5 + */ + public static Object toPrimitive(final Object array) { + if (array == null) { + return null; + } + final Class ct = array.getClass().getComponentType(); + final Class pt = ClassUtils.wrapperToPrimitive(ct); + if (Boolean.TYPE.equals(pt)) { + return toPrimitive((Boolean[]) array); + } + if (Character.TYPE.equals(pt)) { + return toPrimitive((Character[]) array); + } + if (Byte.TYPE.equals(pt)) { + return toPrimitive((Byte[]) array); + } + if (Integer.TYPE.equals(pt)) { + return toPrimitive((Integer[]) array); + } + if (Long.TYPE.equals(pt)) { + return toPrimitive((Long[]) array); + } + if (Short.TYPE.equals(pt)) { + return toPrimitive((Short[]) array); + } + if (Double.TYPE.equals(pt)) { + return toPrimitive((Double[]) array); + } + if (Float.TYPE.equals(pt)) { + return toPrimitive((Float[]) array); + } + return array; + } + + /** + * Converts an array of object Shorts to primitives. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Short} array, may be {@code null}. + * @return a {@code byte} array, {@code null} if null array input. + * @throws NullPointerException if an array element is {@code null}. + */ + public static short[] toPrimitive(final Short[] array) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_SHORT_ARRAY; + } + final short[] result = new short[array.length]; + for (int i = 0; i < array.length; i++) { + result[i] = array[i].shortValue(); + } + return result; + } + + /** + * Converts an array of object Short to primitives handling {@code null}. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array a {@link Short} array, may be {@code null}. + * @param valueForNull the value to insert if {@code null} found. + * @return a {@code byte} array, {@code null} if null array input. + */ + public static short[] toPrimitive(final Short[] array, final short valueForNull) { + if (array == null) { + return null; + } + if (array.length == 0) { + return EMPTY_SHORT_ARRAY; + } + final short[] result = new short[array.length]; + for (int i = 0; i < array.length; i++) { + final Short b = array[i]; + result[i] = b == null ? valueForNull : b.shortValue(); + } + return result; + } + + /** + * Outputs an array as a String, treating {@code null} as an empty array. + *

+ * Multi-dimensional arrays are handled correctly, including + * multi-dimensional primitive arrays. + *

+ *

+ * The format is that of Java source code, for example {@code {a,b}}. + *

+ * + * @param array the array to get a toString for, may be {@code null}. + * @return a String representation of the array, '{}' if null array input. + */ + public static String toString(final Object array) { + return toString(array, "{}"); + } + + /** + * Outputs an array as a String handling {@code null}s. + *

+ * Multi-dimensional arrays are handled correctly, including + * multi-dimensional primitive arrays. + *

+ *

+ * The format is that of Java source code, for example {@code {a,b}}. + *

+ * + * @param array the array to get a toString for, may be {@code null}. + * @param stringIfNull the String to return if the array is {@code null}. + * @return a String representation of the array. + */ + public static String toString(final Object array, final String stringIfNull) { + return array != null ? new ToStringBuilder(array, ToStringStyle.SIMPLE_STYLE).append(array).toString() : stringIfNull; + } + + /** + * Returns an array containing the string representation of each element in the argument array. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the {@code Object[]} to be processed, may be {@code null}. + * @return {@code String[]} of the same size as the source with its element's string representation, {@code null} if null array input. + * @since 3.6 + */ + public static String[] toStringArray(final Object[] array) { + return toStringArray(array, "null"); + } + + /** + * Returns an array containing the string representation of each element in the argument array handling {@code null} elements. + *

+ * This method returns {@code null} for a {@code null} input array. + *

+ * + * @param array the Object[] to be processed, may be {@code null}. + * @param valueForNullElements the value to insert if {@code null} is found. + * @return a {@link String} array, {@code null} if null array input. + * @since 3.6 + */ + public static String[] toStringArray(final Object[] array, final String valueForNullElements) { + if (null == array) { + return null; + } + if (array.length == 0) { + return EMPTY_STRING_ARRAY; + } + return map(array, String.class, e -> Objects.toString(e, valueForNullElements)); + } + + /** + * ArrayUtils instances should NOT be constructed in standard programming. Instead, the class should be used as {@code ArrayUtils.clone(new int[] {2})}. + *

+ * This constructor is public to permit tools that require a JavaBean instance to operate. + *

+ * + * @deprecated TODO Make private in 4.0. + */ + @Deprecated + public ArrayUtils() { + // empty + } +} diff --git a/StringUtils .txt b/StringUtils .txt new file mode 100644 index 0000000..02d32f8 --- /dev/null +++ b/StringUtils .txt @@ -0,0 +1,9243 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * https://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +package org.apache.commons.lang3; + +import java.io.UnsupportedEncodingException; +import java.nio.CharBuffer; +import java.nio.charset.Charset; +import java.text.Normalizer; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.Iterator; +import java.util.List; +import java.util.Locale; +import java.util.Objects; +import java.util.Set; +import java.util.function.Supplier; +import java.util.regex.Pattern; +import java.util.stream.Collectors; + +import org.apache.commons.lang3.function.Suppliers; +import org.apache.commons.lang3.stream.LangCollectors; +import org.apache.commons.lang3.stream.Streams; + +/** + * Operations on {@link String} that are + * {@code null} safe. + * + *
    + *
  • IsEmpty/IsBlank + * - checks if a String contains text
  • + *
  • Trim/Strip + * - removes leading and trailing whitespace
  • + *
  • Equals/Compare + * - compares two strings in a null-safe manner
  • + *
  • startsWith + * - check if a String starts with a prefix in a null-safe manner
  • + *
  • endsWith + * - check if a String ends with a suffix in a null-safe manner
  • + *
  • IndexOf/LastIndexOf/Contains + * - null-safe index-of checks
  • + *
  • IndexOfAny/LastIndexOfAny/IndexOfAnyBut/LastIndexOfAnyBut + * - index-of any of a set of Strings
  • + *
  • ContainsOnly/ContainsNone/ContainsAny + * - checks if String contains only/none/any of these characters
  • + *
  • Substring/Left/Right/Mid + * - null-safe substring extractions
  • + *
  • SubstringBefore/SubstringAfter/SubstringBetween + * - substring extraction relative to other strings
  • + *
  • Split/Join + * - splits a String into an array of substrings and vice versa
  • + *
  • Remove/Delete + * - removes part of a String
  • + *
  • Replace/Overlay + * - Searches a String and replaces one String with another
  • + *
  • Chomp/Chop + * - removes the last part of a String
  • + *
  • AppendIfMissing + * - appends a suffix to the end of the String if not present
  • + *
  • PrependIfMissing + * - prepends a prefix to the start of the String if not present
  • + *
  • LeftPad/RightPad/Center/Repeat + * - pads a String
  • + *
  • UpperCase/LowerCase/SwapCase/Capitalize/Uncapitalize + * - changes the case of a String
  • + *
  • CountMatches + * - counts the number of occurrences of one String in another
  • + *
  • IsAlpha/IsNumeric/IsWhitespace/IsAsciiPrintable + * - checks the characters in a String
  • + *
  • DefaultString + * - protects against a null input String
  • + *
  • Rotate + * - rotate (circular shift) a String
  • + *
  • Reverse/ReverseDelimited + * - reverses a String
  • + *
  • Abbreviate + * - abbreviates a string using ellipses or another given String
  • + *
  • Difference + * - compares Strings and reports on their differences
  • + *
  • LevenshteinDistance + * - the number of changes needed to change one String into another
  • + *
+ * + *

The {@link StringUtils} class defines certain words related to + * String handling.

+ * + *
    + *
  • null - {@code null}
  • + *
  • empty - a zero-length string ({@code ""})
  • + *
  • space - the space character ({@code ' '}, char 32)
  • + *
  • whitespace - the characters defined by {@link Character#isWhitespace(char)}
  • + *
  • trim - the characters <= 32 as in {@link String#trim()}
  • + *
+ * + *

{@link StringUtils} handles {@code null} input Strings quietly. + * That is to say that a {@code null} input will return {@code null}. + * Where a {@code boolean} or {@code int} is being returned + * details vary by method.

+ * + *

A side effect of the {@code null} handling is that a + * {@link NullPointerException} should be considered a bug in + * {@link StringUtils}.

+ * + *

Methods in this class include sample code in their Javadoc comments to explain their operation. + * The symbol {@code *} is used to indicate any input including {@code null}.

+ * + *

#ThreadSafe#

+ * + * @see String + * @since 1.0 + */ +//@Immutable +public class StringUtils { + + // Performance testing notes (JDK 1.4, Jul03, scolebourne) + // Whitespace: + // Character.isWhitespace() is faster than WHITESPACE.indexOf() + // where WHITESPACE is a string of all whitespace characters + // + // Character access: + // String.charAt(n) versus toCharArray(), then array[n] + // String.charAt(n) is about 15% worse for a 10K string + // They are about equal for a length 50 string + // String.charAt(n) is about 4 times better for a length 3 string + // String.charAt(n) is best bet overall + // + // Append: + // String.concat about twice as fast as StringBuffer.append + // (not sure who tested this) + + /** + * This is a 3 character version of an ellipsis. There is a Unicode character for a HORIZONTAL ELLIPSIS, U+2026 '…', this isn't it. + */ + private static final String ELLIPSIS3 = "..."; + + /** + * A String for a space character. + * + * @since 3.2 + */ + public static final String SPACE = " "; + + /** + * The empty String {@code ""}. + * + * @since 2.0 + */ + public static final String EMPTY = ""; + + /** + * The null String {@code null}. Package-private only. + */ + static final String NULL = null; + + /** + * A String for linefeed LF ("\n"). + * + * @see JLF: Escape Sequences + * for Character and String Literals + * @since 3.2 + */ + public static final String LF = "\n"; + + /** + * A String for carriage return CR ("\r"). + * + * @see JLF: Escape Sequences + * for Character and String Literals + * @since 3.2 + */ + public static final String CR = "\r"; + + /** + * Represents a failed index search. + * + * @since 2.1 + */ + public static final int INDEX_NOT_FOUND = -1; + + /** + * The maximum size to which the padding constant(s) can expand. + */ + private static final int PAD_LIMIT = 8192; + + /** + * The default maximum depth at which recursive replacement will continue until no further search replacements are possible. + */ + private static final int DEFAULT_TTL = 5; + + /** + * Pattern used in {@link #stripAccents(String)}. + */ + private static final Pattern STRIP_ACCENTS_PATTERN = Pattern.compile("\\p{InCombiningDiacriticalMarks}+"); //$NON-NLS-1$ + + /** + * Abbreviates a String using ellipses. This will convert "Now is the time for all good men" into "Now is the time for..." + * + *

+ * Specifically: + *

+ *
    + *
  • If the number of characters in {@code str} is less than or equal to {@code maxWidth}, return {@code str}.
  • + *
  • Else abbreviate it to {@code (substring(str, 0, max - 3) + "...")}.
  • + *
  • If {@code maxWidth} is less than {@code 4}, throw an {@link IllegalArgumentException}.
  • + *
  • In no case will it return a String of length greater than {@code maxWidth}.
  • + *
+ * + *
+     * StringUtils.abbreviate(null, *)      = null
+     * StringUtils.abbreviate("", 4)        = ""
+     * StringUtils.abbreviate("abcdefg", 6) = "abc..."
+     * StringUtils.abbreviate("abcdefg", 7) = "abcdefg"
+     * StringUtils.abbreviate("abcdefg", 8) = "abcdefg"
+     * StringUtils.abbreviate("abcdefg", 4) = "a..."
+     * StringUtils.abbreviate("abcdefg", 3) = Throws {@link IllegalArgumentException}.
+     * 
+ * + * @param str the String to check, may be null. + * @param maxWidth maximum length of result String, must be at least 4. + * @return abbreviated String, {@code null} if null String input. + * @throws IllegalArgumentException if the width is too small. + * @since 2.0 + */ + public static String abbreviate(final String str, final int maxWidth) { + return abbreviate(str, ELLIPSIS3, 0, maxWidth); + } + + /** + * Abbreviates a String using ellipses. This will convert "Now is the time for all good men" into "...is the time for...". + * + *

+ * Works like {@code abbreviate(String, int)}, but allows you to specify a "left edge" offset. Note that this left edge is not necessarily going to be the + * leftmost character in the result, or the first character following the ellipses, but it will appear somewhere in the result. + *

+ *

+ * In no case will it return a String of length greater than {@code maxWidth}. + *

+ * + *
+     * StringUtils.abbreviate(null, *, *)                = null
+     * StringUtils.abbreviate("", 0, 4)                  = ""
+     * StringUtils.abbreviate("abcdefghijklmno", -1, 10) = "abcdefg..."
+     * StringUtils.abbreviate("abcdefghijklmno", 0, 10)  = "abcdefg..."
+     * StringUtils.abbreviate("abcdefghijklmno", 1, 10)  = "abcdefg..."
+     * StringUtils.abbreviate("abcdefghijklmno", 4, 10)  = "abcdefg..."
+     * StringUtils.abbreviate("abcdefghijklmno", 5, 10)  = "...fghi..."
+     * StringUtils.abbreviate("abcdefghijklmno", 6, 10)  = "...ghij..."
+     * StringUtils.abbreviate("abcdefghijklmno", 8, 10)  = "...ijklmno"
+     * StringUtils.abbreviate("abcdefghijklmno", 10, 10) = "...ijklmno"
+     * StringUtils.abbreviate("abcdefghijklmno", 12, 10) = "...ijklmno"
+     * StringUtils.abbreviate("abcdefghij", 0, 3)        = Throws {@link IllegalArgumentException}.
+     * StringUtils.abbreviate("abcdefghij", 5, 6)        = Throws {@link IllegalArgumentException}.
+     * 
+ * + * @param str the String to check, may be null. + * @param offset left edge of source String. + * @param maxWidth maximum length of result String, must be at least 4. + * @return abbreviated String, {@code null} if null String input. + * @throws IllegalArgumentException if the width is too small. + * @since 2.0 + */ + public static String abbreviate(final String str, final int offset, final int maxWidth) { + return abbreviate(str, ELLIPSIS3, offset, maxWidth); + } + + /** + * Abbreviates a String using another given String as replacement marker. This will convert "Now is the time for all good men" into "Now is the time for..." + * when "..." is the replacement marker. + * + *

+ * Specifically: + *

+ *
    + *
  • If the number of characters in {@code str} is less than or equal to {@code maxWidth}, return {@code str}.
  • + *
  • Else abbreviate it to {@code (substring(str, 0, max - abbrevMarker.length) + abbrevMarker)}.
  • + *
  • If {@code maxWidth} is less than {@code abbrevMarker.length + 1}, throw an {@link IllegalArgumentException}.
  • + *
  • In no case will it return a String of length greater than {@code maxWidth}.
  • + *
+ * + *
+     * StringUtils.abbreviate(null, "...", *)      = null
+     * StringUtils.abbreviate("abcdefg", null, *)  = "abcdefg"
+     * StringUtils.abbreviate("", "...", 4)        = ""
+     * StringUtils.abbreviate("abcdefg", ".", 5)   = "abcd."
+     * StringUtils.abbreviate("abcdefg", ".", 7)   = "abcdefg"
+     * StringUtils.abbreviate("abcdefg", ".", 8)   = "abcdefg"
+     * StringUtils.abbreviate("abcdefg", "..", 4)  = "ab.."
+     * StringUtils.abbreviate("abcdefg", "..", 3)  = "a.."
+     * StringUtils.abbreviate("abcdefg", "..", 2)  = Throws {@link IllegalArgumentException}.
+     * StringUtils.abbreviate("abcdefg", "...", 3) = Throws {@link IllegalArgumentException}.
+     * 
+ * + * @param str the String to check, may be null. + * @param abbrevMarker the String used as replacement marker. + * @param maxWidth maximum length of result String, must be at least {@code abbrevMarker.length + 1}. + * @return abbreviated String, {@code null} if null String input. + * @throws IllegalArgumentException if the width is too small. + * @since 3.6 + */ + public static String abbreviate(final String str, final String abbrevMarker, final int maxWidth) { + return abbreviate(str, abbrevMarker, 0, maxWidth); + } + + /** + * Abbreviates a String using a given replacement marker. This will convert "Now is the time for all good men" into "...is the time for..." when "..." is + * the replacement marker. + *

+ * Works like {@code abbreviate(String, String, int)}, but allows you to specify a "left edge" offset. Note that this left edge is not necessarily going to + * be the leftmost character in the result, or the first character following the replacement marker, but it will appear somewhere in the result. + *

+ *

+ * In no case will it return a String of length greater than {@code maxWidth}. + *

+ * + *
+     * StringUtils.abbreviate(null, null, *, *)                 = null
+     * StringUtils.abbreviate("abcdefghijklmno", null, *, *)    = "abcdefghijklmno"
+     * StringUtils.abbreviate("", "...", 0, 4)                  = ""
+     * StringUtils.abbreviate("abcdefghijklmno", "---", -1, 10) = "abcdefg---"
+     * StringUtils.abbreviate("abcdefghijklmno", ",", 0, 10)    = "abcdefghi,"
+     * StringUtils.abbreviate("abcdefghijklmno", ",", 1, 10)    = "abcdefghi,"
+     * StringUtils.abbreviate("abcdefghijklmno", ",", 2, 10)    = "abcdefghi,"
+     * StringUtils.abbreviate("abcdefghijklmno", "::", 4, 10)   = "::efghij::"
+     * StringUtils.abbreviate("abcdefghijklmno", "...", 6, 10)  = "...ghij..."
+     * StringUtils.abbreviate("abcdefghijklmno", "…", 6, 10)    = "…ghij…"
+     * StringUtils.abbreviate("abcdefghijklmno", "*", 9, 10)    = "*ghijklmno"
+     * StringUtils.abbreviate("abcdefghijklmno", "'", 10, 10)   = "'ghijklmno"
+     * StringUtils.abbreviate("abcdefghijklmno", "!", 12, 10)   = "!ghijklmno"
+     * StringUtils.abbreviate("abcdefghij", "abra", 0, 4)       = Throws {@link IllegalArgumentException}.
+     * StringUtils.abbreviate("abcdefghij", "...", 5, 6)        = Throws {@link IllegalArgumentException}.
+     * 
+ * + * @param str the String to check, may be null. + * @param abbrevMarker the String used as replacement marker, for example "...", or Unicode HORIZONTAL ELLIPSIS, U+2026 '…'. + * @param offset left edge of source String. + * @param maxWidth maximum length of result String, must be at least 4. + * @return abbreviated String, {@code null} if null String input. + * @throws IllegalArgumentException if the width is too small. + * @since 3.6 + */ + public static String abbreviate(final String str, String abbrevMarker, int offset, final int maxWidth) { + if (isEmpty(str)) { + return str; + } + if (abbrevMarker == null) { + abbrevMarker = EMPTY; + } + final int abbrevMarkerLength = abbrevMarker.length(); + final int minAbbrevWidth = abbrevMarkerLength + 1; + final int minAbbrevWidthOffset = abbrevMarkerLength + abbrevMarkerLength + 1; + + if (maxWidth < minAbbrevWidth) { + throw new IllegalArgumentException(String.format("Minimum abbreviation width is %d", minAbbrevWidth)); + } + final int strLen = str.length(); + if (strLen <= maxWidth) { + return str; + } + if (strLen - offset <= maxWidth - abbrevMarkerLength) { + return abbrevMarker + str.substring(strLen - (maxWidth - abbrevMarkerLength)); + } + if (offset <= abbrevMarkerLength + 1) { + return str.substring(0, maxWidth - abbrevMarkerLength) + abbrevMarker; + } + if (maxWidth < minAbbrevWidthOffset) { + throw new IllegalArgumentException(String.format("Minimum abbreviation width with offset is %d", minAbbrevWidthOffset)); + } + return abbrevMarker + abbreviate(str.substring(offset), abbrevMarker, maxWidth - abbrevMarkerLength); + } + + /** + * Abbreviates a String to the length passed, replacing the middle characters with the supplied replacement String. + * + *

+ * This abbreviation only occurs if the following criteria is met: + *

+ *
    + *
  • Neither the String for abbreviation nor the replacement String are null or empty
  • + *
  • The length to truncate to is less than the length of the supplied String
  • + *
  • The length to truncate to is greater than 0
  • + *
  • The abbreviated String will have enough room for the length supplied replacement String and the first and last characters of the supplied String for + * abbreviation
  • + *
+ *

+ * Otherwise, the returned String will be the same as the supplied String for abbreviation. + *

+ * + *
+     * StringUtils.abbreviateMiddle(null, null, 0)    = null
+     * StringUtils.abbreviateMiddle("abc", null, 0)   = "abc"
+     * StringUtils.abbreviateMiddle("abc", ".", 0)    = "abc"
+     * StringUtils.abbreviateMiddle("abc", ".", 3)    = "abc"
+     * StringUtils.abbreviateMiddle("abcdef", ".", 4) = "ab.f"
+     * 
+ * + * @param str the String to abbreviate, may be null. + * @param middle the String to replace the middle characters with, may be null. + * @param length the length to abbreviate {@code str} to. + * @return the abbreviated String if the above criteria is met, or the original String supplied for abbreviation. + * @since 2.5 + */ + public static String abbreviateMiddle(final String str, final String middle, final int length) { + if (isAnyEmpty(str, middle) || length >= str.length() || length < middle.length() + 2) { + return str; + } + final int targetString = length - middle.length(); + final int startOffset = targetString / 2 + targetString % 2; + final int endOffset = str.length() - targetString / 2; + return str.substring(0, startOffset) + middle + str.substring(endOffset); + } + + /** + * Appends the suffix to the end of the string if the string does not already end with any of the suffixes. + * + *
+     * StringUtils.appendIfMissing(null, null)      = null
+     * StringUtils.appendIfMissing("abc", null)     = "abc"
+     * StringUtils.appendIfMissing("", "xyz"        = "xyz"
+     * StringUtils.appendIfMissing("abc", "xyz")    = "abcxyz"
+     * StringUtils.appendIfMissing("abcxyz", "xyz") = "abcxyz"
+     * StringUtils.appendIfMissing("abcXYZ", "xyz") = "abcXYZxyz"
+     * 
+ *

+ * With additional suffixes, + *

+ * + *
+     * StringUtils.appendIfMissing(null, null, null)       = null
+     * StringUtils.appendIfMissing("abc", null, null)      = "abc"
+     * StringUtils.appendIfMissing("", "xyz", null)        = "xyz"
+     * StringUtils.appendIfMissing("abc", "xyz", new CharSequence[]{null}) = "abcxyz"
+     * StringUtils.appendIfMissing("abc", "xyz", "")       = "abc"
+     * StringUtils.appendIfMissing("abc", "xyz", "mno")    = "abcxyz"
+     * StringUtils.appendIfMissing("abcxyz", "xyz", "mno") = "abcxyz"
+     * StringUtils.appendIfMissing("abcmno", "xyz", "mno") = "abcmno"
+     * StringUtils.appendIfMissing("abcXYZ", "xyz", "mno") = "abcXYZxyz"
+     * StringUtils.appendIfMissing("abcMNO", "xyz", "mno") = "abcMNOxyz"
+     * 
+ * + * @param str The string. + * @param suffix The suffix to append to the end of the string. + * @param suffixes Additional suffixes that are valid terminators. + * @return A new String if suffix was appended, the same string otherwise. + * @since 3.2 + * @deprecated Use {@link Strings#appendIfMissing(String, CharSequence, CharSequence...) Strings.CS.appendIfMissing(String, CharSequence, CharSequence...)}. + */ + @Deprecated + public static String appendIfMissing(final String str, final CharSequence suffix, final CharSequence... suffixes) { + return Strings.CS.appendIfMissing(str, suffix, suffixes); + } + + /** + * Appends the suffix to the end of the string if the string does not + * already end, case-insensitive, with any of the suffixes. + * + *
+     * StringUtils.appendIfMissingIgnoreCase(null, null)      = null
+     * StringUtils.appendIfMissingIgnoreCase("abc", null)     = "abc"
+     * StringUtils.appendIfMissingIgnoreCase("", "xyz")       = "xyz"
+     * StringUtils.appendIfMissingIgnoreCase("abc", "xyz")    = "abcxyz"
+     * StringUtils.appendIfMissingIgnoreCase("abcxyz", "xyz") = "abcxyz"
+     * StringUtils.appendIfMissingIgnoreCase("abcXYZ", "xyz") = "abcXYZ"
+     * 
+ *

With additional suffixes,

+ *
+     * StringUtils.appendIfMissingIgnoreCase(null, null, null)       = null
+     * StringUtils.appendIfMissingIgnoreCase("abc", null, null)      = "abc"
+     * StringUtils.appendIfMissingIgnoreCase("", "xyz", null)        = "xyz"
+     * StringUtils.appendIfMissingIgnoreCase("abc", "xyz", new CharSequence[]{null}) = "abcxyz"
+     * StringUtils.appendIfMissingIgnoreCase("abc", "xyz", "")       = "abc"
+     * StringUtils.appendIfMissingIgnoreCase("abc", "xyz", "mno")    = "abcxyz"
+     * StringUtils.appendIfMissingIgnoreCase("abcxyz", "xyz", "mno") = "abcxyz"
+     * StringUtils.appendIfMissingIgnoreCase("abcmno", "xyz", "mno") = "abcmno"
+     * StringUtils.appendIfMissingIgnoreCase("abcXYZ", "xyz", "mno") = "abcXYZ"
+     * StringUtils.appendIfMissingIgnoreCase("abcMNO", "xyz", "mno") = "abcMNO"
+     * 
+ * + * @param str The string. + * @param suffix The suffix to append to the end of the string. + * @param suffixes Additional suffixes that are valid terminators. + * @return A new String if suffix was appended, the same string otherwise. + * @since 3.2 + * @deprecated Use {@link Strings#appendIfMissing(String, CharSequence, CharSequence...) Strings.CI.appendIfMissing(String, CharSequence, CharSequence...)}. + */ + @Deprecated + public static String appendIfMissingIgnoreCase(final String str, final CharSequence suffix, final CharSequence... suffixes) { + return Strings.CI.appendIfMissing(str, suffix, suffixes); + } + + /** + * Computes the capacity required for a StringBuilder to hold {@code items} of {@code maxElementChars} characters plus the separators between them. The + * separator is assumed to be 1 character. + * + * @param count The number of items. + * @param maxElementChars The maximum number of characters per item. + * @return A StringBuilder with the appropriate capacity. + */ + private static StringBuilder capacity(final int count, final byte maxElementChars) { + return new StringBuilder(count * maxElementChars + count - 1); + } + + /** + * Capitalizes a String changing the first character to title case as per {@link Character#toTitleCase(int)}. No other characters are changed. + * + *

+ * For a word based algorithm, see {@link org.apache.commons.text.WordUtils#capitalize(String)}. A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.capitalize(null)    = null
+     * StringUtils.capitalize("")      = ""
+     * StringUtils.capitalize("cat")   = "Cat"
+     * StringUtils.capitalize("cAt")   = "CAt"
+     * StringUtils.capitalize("'cat'") = "'cat'"
+     * 
+ * + * @param str the String to capitalize, may be null. + * @return the capitalized String, {@code null} if null String input. + * @see org.apache.commons.text.WordUtils#capitalize(String) + * @see #uncapitalize(String) + * @since 2.0 + */ + public static String capitalize(final String str) { + if (isEmpty(str)) { + return str; + } + final int firstCodepoint = str.codePointAt(0); + final int newCodePoint = Character.toTitleCase(firstCodepoint); + if (firstCodepoint == newCodePoint) { + // already capitalized + return str; + } + final int[] newCodePoints = str.codePoints().toArray(); + newCodePoints[0] = newCodePoint; // copy the first code point + return new String(newCodePoints, 0, newCodePoints.length); + } + + /** + * Centers a String in a larger String of size {@code size} using the space character (' '). + * + *

+ * If the size is less than the String length, the original String is returned. A {@code null} String returns {@code null}. A negative size is treated as + * zero. + *

+ * + *

+ * Equivalent to {@code center(str, size, " ")}. + *

+ * + *
+     * StringUtils.center(null, *)   = null
+     * StringUtils.center("", 4)     = "    "
+     * StringUtils.center("ab", -1)  = "ab"
+     * StringUtils.center("ab", 4)   = " ab "
+     * StringUtils.center("abcd", 2) = "abcd"
+     * StringUtils.center("a", 4)    = " a  "
+     * 
+ * + * @param str the String to center, may be null. + * @param size the int size of new String, negative treated as zero. + * @return centered String, {@code null} if null String input. + */ + public static String center(final String str, final int size) { + return center(str, size, ' '); + } + + /** + * Centers a String in a larger String of size {@code size}. Uses a supplied character as the value to pad the String with. + * + *

+ * If the size is less than the String length, the String is returned. A {@code null} String returns {@code null}. A negative size is treated as zero. + *

+ * + *
+     * StringUtils.center(null, *, *)     = null
+     * StringUtils.center("", 4, ' ')     = "    "
+     * StringUtils.center("ab", -1, ' ')  = "ab"
+     * StringUtils.center("ab", 4, ' ')   = " ab "
+     * StringUtils.center("abcd", 2, ' ') = "abcd"
+     * StringUtils.center("a", 4, ' ')    = " a  "
+     * StringUtils.center("a", 4, 'y')    = "yayy"
+     * 
+ * + * @param str the String to center, may be null. + * @param size the int size of new String, negative treated as zero. + * @param padChar the character to pad the new String with. + * @return centered String, {@code null} if null String input. + * @since 2.0 + */ + public static String center(String str, final int size, final char padChar) { + if (str == null || size <= 0) { + return str; + } + final int strLen = str.length(); + final int pads = size - strLen; + if (pads <= 0) { + return str; + } + str = leftPad(str, strLen + pads / 2, padChar); + return rightPad(str, size, padChar); + } + + /** + * Centers a String in a larger String of size {@code size}. Uses a supplied String as the value to pad the String with. + * + *

+ * If the size is less than the String length, the String is returned. A {@code null} String returns {@code null}. A negative size is treated as zero. + *

+ * + *
+     * StringUtils.center(null, *, *)     = null
+     * StringUtils.center("", 4, " ")     = "    "
+     * StringUtils.center("ab", -1, " ")  = "ab"
+     * StringUtils.center("ab", 4, " ")   = " ab "
+     * StringUtils.center("abcd", 2, " ") = "abcd"
+     * StringUtils.center("a", 4, " ")    = " a  "
+     * StringUtils.center("a", 4, "yz")   = "yayz"
+     * StringUtils.center("abc", 7, null) = "  abc  "
+     * StringUtils.center("abc", 7, "")   = "  abc  "
+     * 
+ * + * @param str the String to center, may be null. + * @param size the int size of new String, negative treated as zero. + * @param padStr the String to pad the new String with, must not be null or empty. + * @return centered String, {@code null} if null String input. + * @throws IllegalArgumentException if padStr is {@code null} or empty. + */ + public static String center(String str, final int size, String padStr) { + if (str == null || size <= 0) { + return str; + } + if (isEmpty(padStr)) { + padStr = SPACE; + } + final int strLen = str.length(); + final int pads = size - strLen; + if (pads <= 0) { + return str; + } + str = leftPad(str, strLen + pads / 2, padStr); + return rightPad(str, size, padStr); + } + + /** + * Removes one newline from end of a String if it's there, otherwise leave it alone. A newline is "{@code \n}", "{@code \r}", or + * "{@code \r\n}". + * + *

+ * NOTE: This method changed in 2.0. It now more closely matches Perl chomp. + *

+ * + *
+     * StringUtils.chomp(null)          = null
+     * StringUtils.chomp("")            = ""
+     * StringUtils.chomp("abc \r")      = "abc "
+     * StringUtils.chomp("abc\n")       = "abc"
+     * StringUtils.chomp("abc\r\n")     = "abc"
+     * StringUtils.chomp("abc\r\n\r\n") = "abc\r\n"
+     * StringUtils.chomp("abc\n\r")     = "abc\n"
+     * StringUtils.chomp("abc\n\rabc")  = "abc\n\rabc"
+     * StringUtils.chomp("\r")          = ""
+     * StringUtils.chomp("\n")          = ""
+     * StringUtils.chomp("\r\n")        = ""
+     * 
+ * + * @param str the String to chomp a newline from, may be null. + * @return String without newline, {@code null} if null String input. + */ + public static String chomp(final String str) { + if (isEmpty(str)) { + return str; + } + if (str.length() == 1) { + final char ch = str.charAt(0); + if (ch == CharUtils.CR || ch == CharUtils.LF) { + return EMPTY; + } + return str; + } + int lastIdx = str.length() - 1; + final char last = str.charAt(lastIdx); + if (last == CharUtils.LF) { + if (str.charAt(lastIdx - 1) == CharUtils.CR) { + lastIdx--; + } + } else if (last != CharUtils.CR) { + lastIdx++; + } + return str.substring(0, lastIdx); + } + + /** + * Removes {@code separator} from the end of {@code str} if it's there, otherwise leave it alone. + * + *

+ * NOTE: This method changed in version 2.0. It now more closely matches Perl chomp. For the previous behavior, use + * {@link #substringBeforeLast(String, String)}. This method uses {@link String#endsWith(String)}. + *

+ * + *
+     * StringUtils.chomp(null, *)         = null
+     * StringUtils.chomp("", *)           = ""
+     * StringUtils.chomp("foobar", "bar") = "foo"
+     * StringUtils.chomp("foobar", "baz") = "foobar"
+     * StringUtils.chomp("foo", "foo")    = ""
+     * StringUtils.chomp("foo ", "foo")   = "foo "
+     * StringUtils.chomp(" foo", "foo")   = " "
+     * StringUtils.chomp("foo", "foooo")  = "foo"
+     * StringUtils.chomp("foo", "")       = "foo"
+     * StringUtils.chomp("foo", null)     = "foo"
+     * 
+ * + * @param str the String to chomp from, may be null. + * @param separator separator String, may be null. + * @return String without trailing separator, {@code null} if null String input. + * @deprecated This feature will be removed in Lang 4, use {@link StringUtils#removeEnd(String, String)} instead. + */ + @Deprecated + public static String chomp(final String str, final String separator) { + return Strings.CS.removeEnd(str, separator); + } + + /** + * Removes the last character from a String. + * + *

+ * If the String ends in {@code \r\n}, then remove both of them. + *

+ * + *
+     * StringUtils.chop(null)          = null
+     * StringUtils.chop("")            = ""
+     * StringUtils.chop("abc \r")      = "abc "
+     * StringUtils.chop("abc\n")       = "abc"
+     * StringUtils.chop("abc\r\n")     = "abc"
+     * StringUtils.chop("abc")         = "ab"
+     * StringUtils.chop("abc\nabc")    = "abc\nab"
+     * StringUtils.chop("a")           = ""
+     * StringUtils.chop("\r")          = ""
+     * StringUtils.chop("\n")          = ""
+     * StringUtils.chop("\r\n")        = ""
+     * 
+ * + * @param str the String to chop last character from, may be null. + * @return String without last character, {@code null} if null String input. + */ + public static String chop(final String str) { + if (str == null) { + return null; + } + final int strLen = str.length(); + if (strLen < 2) { + return EMPTY; + } + final int lastIdx = strLen - 1; + final String ret = str.substring(0, lastIdx); + final char last = str.charAt(lastIdx); + if (last == CharUtils.LF && ret.charAt(lastIdx - 1) == CharUtils.CR) { + return ret.substring(0, lastIdx - 1); + } + return ret; + } + + /** + * Compares two Strings lexicographically, as per {@link String#compareTo(String)}, returning : + *
    + *
  • {@code int = 0}, if {@code str1} is equal to {@code str2} (or both {@code null})
  • + *
  • {@code int < 0}, if {@code str1} is less than {@code str2}
  • + *
  • {@code int > 0}, if {@code str1} is greater than {@code str2}
  • + *
+ * + *

+ * This is a {@code null} safe version of: + *

+ * + *
+     * str1.compareTo(str2)
+     * 
+ * + *

+ * {@code null} value is considered less than non-{@code null} value. Two {@code null} references are considered equal. + *

+ * + *
{@code
+     * StringUtils.compare(null, null)   = 0
+     * StringUtils.compare(null , "a")   < 0
+     * StringUtils.compare("a", null)   > 0
+     * StringUtils.compare("abc", "abc") = 0
+     * StringUtils.compare("a", "b")     < 0
+     * StringUtils.compare("b", "a")     > 0
+     * StringUtils.compare("a", "B")     > 0
+     * StringUtils.compare("ab", "abc")  < 0
+     * }
+ * + * @param str1 the String to compare from. + * @param str2 the String to compare to. + * @return < 0, 0, > 0, if {@code str1} is respectively less, equal or greater than {@code str2}. + * @see #compare(String, String, boolean) + * @see String#compareTo(String) + * @since 3.5 + * @deprecated Use {@link Strings#compare(String, String) Strings.CS.compare(String, String)}. + */ + @Deprecated + public static int compare(final String str1, final String str2) { + return Strings.CS.compare(str1, str2); + } + + /** + * Compares two Strings lexicographically, as per {@link String#compareTo(String)}, returning : + *
    + *
  • {@code int = 0}, if {@code str1} is equal to {@code str2} (or both {@code null})
  • + *
  • {@code int < 0}, if {@code str1} is less than {@code str2}
  • + *
  • {@code int > 0}, if {@code str1} is greater than {@code str2}
  • + *
+ * + *

+ * This is a {@code null} safe version of : + *

+ * + *
+     * str1.compareTo(str2)
+     * 
+ * + *

+ * {@code null} inputs are handled according to the {@code nullIsLess} parameter. Two {@code null} references are considered equal. + *

+ * + *
{@code
+     * StringUtils.compare(null, null, *)     = 0
+     * StringUtils.compare(null , "a", true)  < 0
+     * StringUtils.compare(null , "a", false) > 0
+     * StringUtils.compare("a", null, true)   > 0
+     * StringUtils.compare("a", null, false)  < 0
+     * StringUtils.compare("abc", "abc", *)   = 0
+     * StringUtils.compare("a", "b", *)       < 0
+     * StringUtils.compare("b", "a", *)       > 0
+     * StringUtils.compare("a", "B", *)       > 0
+     * StringUtils.compare("ab", "abc", *)    < 0
+     * }
+ * + * @param str1 the String to compare from. + * @param str2 the String to compare to. + * @param nullIsLess whether consider {@code null} value less than non-{@code null} value. + * @return < 0, 0, > 0, if {@code str1} is respectively less, equal ou greater than {@code str2}. + * @see String#compareTo(String) + * @since 3.5 + */ + public static int compare(final String str1, final String str2, final boolean nullIsLess) { + if (str1 == str2) { // NOSONARLINT this intentionally uses == to allow for both null + return 0; + } + if (str1 == null) { + return nullIsLess ? -1 : 1; + } + if (str2 == null) { + return nullIsLess ? 1 : -1; + } + return str1.compareTo(str2); + } + + /** + * Compares two Strings lexicographically, ignoring case differences, as per {@link String#compareToIgnoreCase(String)}, returning : + *
    + *
  • {@code int = 0}, if {@code str1} is equal to {@code str2} (or both {@code null})
  • + *
  • {@code int < 0}, if {@code str1} is less than {@code str2}
  • + *
  • {@code int > 0}, if {@code str1} is greater than {@code str2}
  • + *
+ * + *

+ * This is a {@code null} safe version of: + *

+ * + *
+     * str1.compareToIgnoreCase(str2)
+     * 
+ * + *

+ * {@code null} value is considered less than non-{@code null} value. Two {@code null} references are considered equal. Comparison is case insensitive. + *

+ * + *
{@code
+     * StringUtils.compareIgnoreCase(null, null)   = 0
+     * StringUtils.compareIgnoreCase(null , "a")   < 0
+     * StringUtils.compareIgnoreCase("a", null)    > 0
+     * StringUtils.compareIgnoreCase("abc", "abc") = 0
+     * StringUtils.compareIgnoreCase("abc", "ABC") = 0
+     * StringUtils.compareIgnoreCase("a", "b")     < 0
+     * StringUtils.compareIgnoreCase("b", "a")     > 0
+     * StringUtils.compareIgnoreCase("a", "B")     < 0
+     * StringUtils.compareIgnoreCase("A", "b")     < 0
+     * StringUtils.compareIgnoreCase("ab", "ABC")  < 0
+     * }
+ * + * @param str1 the String to compare from. + * @param str2 the String to compare to. + * @return < 0, 0, > 0, if {@code str1} is respectively less, equal ou greater than {@code str2}, ignoring case differences. + * @see #compareIgnoreCase(String, String, boolean) + * @see String#compareToIgnoreCase(String) + * @since 3.5 + * @deprecated Use {@link Strings#compare(String, String) Strings.CI.compare(String, String)}. + */ + @Deprecated + public static int compareIgnoreCase(final String str1, final String str2) { + return Strings.CI.compare(str1, str2); + } + + /** + * Compares two Strings lexicographically, ignoring case differences, as per {@link String#compareToIgnoreCase(String)}, returning : + *
    + *
  • {@code int = 0}, if {@code str1} is equal to {@code str2} (or both {@code null})
  • + *
  • {@code int < 0}, if {@code str1} is less than {@code str2}
  • + *
  • {@code int > 0}, if {@code str1} is greater than {@code str2}
  • + *
+ * + *

+ * This is a {@code null} safe version of : + *

+ *
+     * str1.compareToIgnoreCase(str2)
+     * 
+ * + *

+ * {@code null} inputs are handled according to the {@code nullIsLess} parameter. Two {@code null} references are considered equal. Comparison is case + * insensitive. + *

+ * + *
{@code
+     * StringUtils.compareIgnoreCase(null, null, *)     = 0
+     * StringUtils.compareIgnoreCase(null , "a", true)  < 0
+     * StringUtils.compareIgnoreCase(null , "a", false) > 0
+     * StringUtils.compareIgnoreCase("a", null, true)   > 0
+     * StringUtils.compareIgnoreCase("a", null, false)  < 0
+     * StringUtils.compareIgnoreCase("abc", "abc", *)   = 0
+     * StringUtils.compareIgnoreCase("abc", "ABC", *)   = 0
+     * StringUtils.compareIgnoreCase("a", "b", *)       < 0
+     * StringUtils.compareIgnoreCase("b", "a", *)       > 0
+     * StringUtils.compareIgnoreCase("a", "B", *)       < 0
+     * StringUtils.compareIgnoreCase("A", "b", *)       < 0
+     * StringUtils.compareIgnoreCase("ab", "abc", *)    < 0
+     * }
+ * + * @param str1 the String to compare from. + * @param str2 the String to compare to. + * @param nullIsLess whether consider {@code null} value less than non-{@code null} value. + * @return < 0, 0, > 0, if {@code str1} is respectively less, equal ou greater than {@code str2}, ignoring case differences. + * @see String#compareToIgnoreCase(String) + * @since 3.5 + */ + public static int compareIgnoreCase(final String str1, final String str2, final boolean nullIsLess) { + if (str1 == str2) { // NOSONARLINT this intentionally uses == to allow for both null + return 0; + } + if (str1 == null) { + return nullIsLess ? -1 : 1; + } + if (str2 == null) { + return nullIsLess ? 1 : -1; + } + return str1.compareToIgnoreCase(str2); + } + + /** + * Tests if CharSequence contains a search CharSequence, handling {@code null}. + * This method uses {@link String#indexOf(String)} if possible. + * + *

A {@code null} CharSequence will return {@code false}.

+ * + *
+     * StringUtils.contains(null, *)     = false
+     * StringUtils.contains(*, null)     = false
+     * StringUtils.contains("", "")      = true
+     * StringUtils.contains("abc", "")   = true
+     * StringUtils.contains("abc", "a")  = true
+     * StringUtils.contains("abc", "z")  = false
+     * 
+ * + * @param seq the CharSequence to check, may be null + * @param searchSeq the CharSequence to find, may be null + * @return true if the CharSequence contains the search CharSequence, + * false if not or {@code null} string input + * @since 2.0 + * @since 3.0 Changed signature from contains(String, String) to contains(CharSequence, CharSequence) + * @deprecated Use {@link Strings#contains(CharSequence, CharSequence) Strings.CS.contains(CharSequence, CharSequence)}. + */ + @Deprecated + public static boolean contains(final CharSequence seq, final CharSequence searchSeq) { + return Strings.CS.contains(seq, searchSeq); + } + + /** + * Tests if CharSequence contains a search character, handling {@code null}. This method uses {@link String#indexOf(int)} if possible. + * + *

+ * A {@code null} or empty ("") CharSequence will return {@code false}. + *

+ * + *
+     * StringUtils.contains(null, *)    = false
+     * StringUtils.contains("", *)      = false
+     * StringUtils.contains("abc", 'a') = true
+     * StringUtils.contains("abc", 'z') = false
+     * 
+ * + * @param seq the CharSequence to check, may be null + * @param searchChar the character to find + * @return true if the CharSequence contains the search character, false if not or {@code null} string input + * @since 2.0 + * @since 3.0 Changed signature from contains(String, int) to contains(CharSequence, int) + */ + public static boolean contains(final CharSequence seq, final int searchChar) { + if (isEmpty(seq)) { + return false; + } + return CharSequenceUtils.indexOf(seq, searchChar, 0) >= 0; + } + + /** + * Tests if the CharSequence contains any character in the given set of characters. + * + *

+ * A {@code null} CharSequence will return {@code false}. A {@code null} or zero length search array will return {@code false}. + *

+ * + *
+     * StringUtils.containsAny(null, *)                  = false
+     * StringUtils.containsAny("", *)                    = false
+     * StringUtils.containsAny(*, null)                  = false
+     * StringUtils.containsAny(*, [])                    = false
+     * StringUtils.containsAny("zzabyycdxx", 'z', 'a')   = true
+     * StringUtils.containsAny("zzabyycdxx", 'b', 'y')   = true
+     * StringUtils.containsAny("zzabyycdxx", 'z', 'y')   = true
+     * StringUtils.containsAny("aba", 'z])               = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param searchChars the chars to search for, may be null. + * @return the {@code true} if any of the chars are found, {@code false} if no match or null input. + * @since 2.4 + * @since 3.0 Changed signature from containsAny(String, char[]) to containsAny(CharSequence, char...) + */ + public static boolean containsAny(final CharSequence cs, final char... searchChars) { + if (isEmpty(cs) || ArrayUtils.isEmpty(searchChars)) { + return false; + } + final int csLength = cs.length(); + final int searchLength = searchChars.length; + final int csLast = csLength - 1; + final int searchLast = searchLength - 1; + for (int i = 0; i < csLength; i++) { + final char ch = cs.charAt(i); + for (int j = 0; j < searchLength; j++) { + if (searchChars[j] == ch) { + if (!Character.isHighSurrogate(ch) || j == searchLast || i < csLast && searchChars[j + 1] == cs.charAt(i + 1)) { + return true; + } + } + } + } + return false; + } + + /** + * Tests if the CharSequence contains any character in the given set of characters. + * + *

+ * A {@code null} CharSequence will return {@code false}. A {@code null} search CharSequence will return {@code false}. + *

+ * + *
+     * StringUtils.containsAny(null, *)               = false
+     * StringUtils.containsAny("", *)                 = false
+     * StringUtils.containsAny(*, null)               = false
+     * StringUtils.containsAny(*, "")                 = false
+     * StringUtils.containsAny("zzabyycdxx", "za")    = true
+     * StringUtils.containsAny("zzabyycdxx", "by")    = true
+     * StringUtils.containsAny("zzabyycdxx", "zy")    = true
+     * StringUtils.containsAny("zzabyycdxx", "\tx")   = true
+     * StringUtils.containsAny("zzabyycdxx", "$.#yF") = true
+     * StringUtils.containsAny("aba", "z")            = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param searchChars the chars to search for, may be null. + * @return the {@code true} if any of the chars are found, {@code false} if no match or null input. + * @since 2.4 + * @since 3.0 Changed signature from containsAny(String, String) to containsAny(CharSequence, CharSequence) + */ + public static boolean containsAny(final CharSequence cs, final CharSequence searchChars) { + if (searchChars == null) { + return false; + } + return containsAny(cs, CharSequenceUtils.toCharArray(searchChars)); + } + + /** + * Tests if the CharSequence contains any of the CharSequences in the given array. + * + *

+ * A {@code null} {@code cs} CharSequence will return {@code false}. A {@code null} or zero length search array will + * return {@code false}. + *

+ * + *
+     * StringUtils.containsAny(null, *)            = false
+     * StringUtils.containsAny("", *)              = false
+     * StringUtils.containsAny(*, null)            = false
+     * StringUtils.containsAny(*, [])              = false
+     * StringUtils.containsAny("abcd", "ab", null) = true
+     * StringUtils.containsAny("abcd", "ab", "cd") = true
+     * StringUtils.containsAny("abc", "d", "abc")  = true
+     * 
+ * + * @param cs The CharSequence to check, may be null. + * @param searchCharSequences The array of CharSequences to search for, may be null. Individual CharSequences may be + * null as well. + * @return {@code true} if any of the search CharSequences are found, {@code false} otherwise. + * @since 3.4 + * @deprecated Use {@link Strings#containsAny(CharSequence, CharSequence...) Strings.CS.containsAny(CharSequence, CharSequence...)}. + */ + @Deprecated + public static boolean containsAny(final CharSequence cs, final CharSequence... searchCharSequences) { + return Strings.CS.containsAny(cs, searchCharSequences); + } + + /** + * Tests if the CharSequence contains any of the CharSequences in the given array, ignoring case. + * + *

+ * A {@code null} {@code cs} CharSequence will return {@code false}. A {@code null} or zero length search array will + * return {@code false}. + *

+ * + *
+     * StringUtils.containsAny(null, *)            = false
+     * StringUtils.containsAny("", *)              = false
+     * StringUtils.containsAny(*, null)            = false
+     * StringUtils.containsAny(*, [])              = false
+     * StringUtils.containsAny("abcd", "ab", null) = true
+     * StringUtils.containsAny("abcd", "ab", "cd") = true
+     * StringUtils.containsAny("abc", "d", "abc")  = true
+     * StringUtils.containsAny("abc", "D", "ABC")  = true
+     * StringUtils.containsAny("ABC", "d", "abc")  = true
+     * 
+ * + * @param cs The CharSequence to check, may be null. + * @param searchCharSequences The array of CharSequences to search for, may be null. Individual CharSequences may be + * null as well. + * @return {@code true} if any of the search CharSequences are found, {@code false} otherwise + * @since 3.12.0 + * @deprecated Use {@link Strings#containsAny(CharSequence, CharSequence...) Strings.CI.containsAny(CharSequence, CharSequence...)}. + */ + @Deprecated + public static boolean containsAnyIgnoreCase(final CharSequence cs, final CharSequence... searchCharSequences) { + return Strings.CI.containsAny(cs, searchCharSequences); + } + + /** + * Tests if CharSequence contains a search CharSequence irrespective of case, handling {@code null}. Case-insensitivity is defined as by + * {@link String#equalsIgnoreCase(String)}. + * + *

+ * A {@code null} CharSequence will return {@code false}. + *

+ * + *
+     * StringUtils.containsIgnoreCase(null, *)    = false
+     * StringUtils.containsIgnoreCase(*, null)    = false
+     * StringUtils.containsIgnoreCase("", "")     = true
+     * StringUtils.containsIgnoreCase("abc", "")  = true
+     * StringUtils.containsIgnoreCase("abc", "a") = true
+     * StringUtils.containsIgnoreCase("abc", "z") = false
+     * StringUtils.containsIgnoreCase("abc", "A") = true
+     * StringUtils.containsIgnoreCase("abc", "Z") = false
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStr the CharSequence to find, may be null. + * @return true if the CharSequence contains the search CharSequence irrespective of case or false if not or {@code null} string input. + * @since 3.0 Changed signature from containsIgnoreCase(String, String) to containsIgnoreCase(CharSequence, CharSequence). + * @deprecated Use {@link Strings#contains(CharSequence, CharSequence) Strings.CI.contains(CharSequence, CharSequence)}. + */ + @Deprecated + public static boolean containsIgnoreCase(final CharSequence str, final CharSequence searchStr) { + return Strings.CI.contains(str, searchStr); + } + + /** + * Tests that the CharSequence does not contain certain characters. + * + *

+ * A {@code null} CharSequence will return {@code true}. A {@code null} invalid character array will return {@code true}. An empty CharSequence (length()=0) + * always returns true. + *

+ * + *
+     * StringUtils.containsNone(null, *)               = true
+     * StringUtils.containsNone(*, null)               = true
+     * StringUtils.containsNone("", *)                 = true
+     * StringUtils.containsNone("ab", '')              = true
+     * StringUtils.containsNone("abab", 'x', 'y', 'z') = true
+     * StringUtils.containsNone("ab1", 'x', 'y', 'z')  = true
+     * StringUtils.containsNone("abz", 'x', 'y', 'z')  = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param searchChars an array of invalid chars, may be null. + * @return true if it contains none of the invalid chars, or is null. + * @since 2.0 + * @since 3.0 Changed signature from containsNone(String, char[]) to containsNone(CharSequence, char...) + */ + public static boolean containsNone(final CharSequence cs, final char... searchChars) { + if (cs == null || searchChars == null) { + return true; + } + final int csLen = cs.length(); + final int csLast = csLen - 1; + final int searchLen = searchChars.length; + final int searchLast = searchLen - 1; + for (int i = 0; i < csLen; i++) { + final char ch = cs.charAt(i); + for (int j = 0; j < searchLen; j++) { + if (searchChars[j] == ch) { + if (!Character.isHighSurrogate(ch) || j == searchLast || i < csLast && searchChars[j + 1] == cs.charAt(i + 1)) { + return false; + } + } + } + } + return true; + } + + /** + * Tests that the CharSequence does not contain certain characters. + * + *

+ * A {@code null} CharSequence will return {@code true}. A {@code null} invalid character array will return {@code true}. An empty String ("") always + * returns true. + *

+ * + *
+     * StringUtils.containsNone(null, *)       = true
+     * StringUtils.containsNone(*, null)       = true
+     * StringUtils.containsNone("", *)         = true
+     * StringUtils.containsNone("ab", "")      = true
+     * StringUtils.containsNone("abab", "xyz") = true
+     * StringUtils.containsNone("ab1", "xyz")  = true
+     * StringUtils.containsNone("abz", "xyz")  = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param invalidChars a String of invalid chars, may be null. + * @return true if it contains none of the invalid chars, or is null. + * @since 2.0 + * @since 3.0 Changed signature from containsNone(String, String) to containsNone(CharSequence, String) + */ + public static boolean containsNone(final CharSequence cs, final String invalidChars) { + if (invalidChars == null) { + return true; + } + return containsNone(cs, invalidChars.toCharArray()); + } + + /** + * Tests if the CharSequence contains only certain characters. + * + *

+ * A {@code null} CharSequence will return {@code false}. A {@code null} valid character array will return {@code false}. An empty CharSequence (length()=0) + * always returns {@code true}. + *

+ * + *
+     * StringUtils.containsOnly(null, *)               = false
+     * StringUtils.containsOnly(*, null)               = false
+     * StringUtils.containsOnly("", *)                 = true
+     * StringUtils.containsOnly("ab", '')              = false
+     * StringUtils.containsOnly("abab", 'a', 'b', 'c') = true
+     * StringUtils.containsOnly("ab1", 'a', 'b', 'c')  = false
+     * StringUtils.containsOnly("abz", 'a', 'b', 'c')  = false
+     * 
+ * + * @param cs the String to check, may be null. + * @param valid an array of valid chars, may be null. + * @return true if it only contains valid chars and is non-null. + * @since 3.0 Changed signature from containsOnly(String, char[]) to containsOnly(CharSequence, char...) + */ + public static boolean containsOnly(final CharSequence cs, final char... valid) { + // All these pre-checks are to maintain API with an older version + if (valid == null || cs == null) { + return false; + } + if (cs.length() == 0) { + return true; + } + if (valid.length == 0) { + return false; + } + return indexOfAnyBut(cs, valid) == INDEX_NOT_FOUND; + } + + /** + * Tests if the CharSequence contains only certain characters. + * + *

+ * A {@code null} CharSequence will return {@code false}. A {@code null} valid character String will return {@code false}. An empty String (length()=0) + * always returns {@code true}. + *

+ * + *
+     * StringUtils.containsOnly(null, *)       = false
+     * StringUtils.containsOnly(*, null)       = false
+     * StringUtils.containsOnly("", *)         = true
+     * StringUtils.containsOnly("ab", "")      = false
+     * StringUtils.containsOnly("abab", "abc") = true
+     * StringUtils.containsOnly("ab1", "abc")  = false
+     * StringUtils.containsOnly("abz", "abc")  = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param validChars a String of valid chars, may be null. + * @return true if it only contains valid chars and is non-null. + * @since 2.0 + * @since 3.0 Changed signature from containsOnly(String, String) to containsOnly(CharSequence, String) + */ + public static boolean containsOnly(final CharSequence cs, final String validChars) { + if (cs == null || validChars == null) { + return false; + } + return containsOnly(cs, validChars.toCharArray()); + } + + /** + * Tests whether the given CharSequence contains any whitespace characters. + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.containsWhitespace(null)       = false
+     * StringUtils.containsWhitespace("")         = false
+     * StringUtils.containsWhitespace("ab")       = false
+     * StringUtils.containsWhitespace(" ab")      = true
+     * StringUtils.containsWhitespace("a b")      = true
+     * StringUtils.containsWhitespace("ab ")      = true
+     * 
+ * + * @param seq the CharSequence to check (may be {@code null}). + * @return {@code true} if the CharSequence is not empty and contains at least 1 (breaking) whitespace character. + * @since 3.0 + */ + public static boolean containsWhitespace(final CharSequence seq) { + if (isEmpty(seq)) { + return false; + } + final int strLen = seq.length(); + for (int i = 0; i < strLen; i++) { + if (Character.isWhitespace(seq.charAt(i))) { + return true; + } + } + return false; + } + + private static void convertRemainingAccentCharacters(final StringBuilder decomposed) { + for (int i = 0; i < decomposed.length(); i++) { + final char charAt = decomposed.charAt(i); + switch (charAt) { + case '\u0141': + decomposed.setCharAt(i, 'L'); + break; + case '\u0142': + decomposed.setCharAt(i, 'l'); + break; + // D with stroke + case '\u0110': + // LATIN CAPITAL LETTER D WITH STROKE + decomposed.setCharAt(i, 'D'); + break; + case '\u0111': + // LATIN SMALL LETTER D WITH STROKE + decomposed.setCharAt(i, 'd'); + break; + // I with bar + case '\u0197': + decomposed.setCharAt(i, 'I'); + break; + case '\u0268': + decomposed.setCharAt(i, 'i'); + break; + case '\u1D7B': + decomposed.setCharAt(i, 'I'); + break; + case '\u1DA4': + decomposed.setCharAt(i, 'i'); + break; + case '\u1DA7': + decomposed.setCharAt(i, 'I'); + break; + // U with bar + case '\u0244': + // LATIN CAPITAL LETTER U BAR + decomposed.setCharAt(i, 'U'); + break; + case '\u0289': + // LATIN SMALL LETTER U BAR + decomposed.setCharAt(i, 'u'); + break; + case '\u1D7E': + // LATIN SMALL CAPITAL LETTER U WITH STROKE + decomposed.setCharAt(i, 'U'); + break; + case '\u1DB6': + // MODIFIER LETTER SMALL U BAR + decomposed.setCharAt(i, 'u'); + break; + // T with stroke + case '\u0166': + // LATIN CAPITAL LETTER T WITH STROKE + decomposed.setCharAt(i, 'T'); + break; + case '\u0167': + // LATIN SMALL LETTER T WITH STROKE + decomposed.setCharAt(i, 't'); + break; + default: + break; + } + } + } + + /** + * Counts how many times the char appears in the given string. + * + *

+ * A {@code null} or empty ("") String input returns {@code 0}. + *

+ * + *
+     * StringUtils.countMatches(null, *)     = 0
+     * StringUtils.countMatches("", *)       = 0
+     * StringUtils.countMatches("abba", 0)   = 0
+     * StringUtils.countMatches("abba", 'a') = 2
+     * StringUtils.countMatches("abba", 'b') = 2
+     * StringUtils.countMatches("abba", 'x') = 0
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param ch the char to count. + * @return the number of occurrences, 0 if the CharSequence is {@code null}. + * @since 3.4 + */ + public static int countMatches(final CharSequence str, final char ch) { + if (isEmpty(str)) { + return 0; + } + int count = 0; + // We could also call str.toCharArray() for faster lookups but that would generate more garbage. + for (int i = 0; i < str.length(); i++) { + if (ch == str.charAt(i)) { + count++; + } + } + return count; + } + + /** + * Counts how many times the substring appears in the larger string. Note that the code only counts non-overlapping matches. + * + *

+ * A {@code null} or empty ("") String input returns {@code 0}. + *

+ * + *
+     * StringUtils.countMatches(null, *)        = 0
+     * StringUtils.countMatches("", *)          = 0
+     * StringUtils.countMatches("abba", null)   = 0
+     * StringUtils.countMatches("abba", "")     = 0
+     * StringUtils.countMatches("abba", "a")    = 2
+     * StringUtils.countMatches("abba", "ab")   = 1
+     * StringUtils.countMatches("abba", "xxx")  = 0
+     * StringUtils.countMatches("ababa", "aba") = 1
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param sub the substring to count, may be null. + * @return the number of occurrences, 0 if either CharSequence is {@code null}. + * @since 3.0 Changed signature from countMatches(String, String) to countMatches(CharSequence, CharSequence) + */ + public static int countMatches(final CharSequence str, final CharSequence sub) { + if (isEmpty(str) || isEmpty(sub)) { + return 0; + } + int count = 0; + int idx = 0; + while ((idx = CharSequenceUtils.indexOf(str, sub, idx)) != INDEX_NOT_FOUND) { + count++; + idx += sub.length(); + } + return count; + } + + /** + * Returns either the passed in CharSequence, or if the CharSequence is {@link #isBlank(CharSequence) blank} (whitespaces, empty ({@code ""}), or + * {@code null}), the value of {@code defaultStr}. + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.defaultIfBlank(null, "NULL")  = "NULL"
+     * StringUtils.defaultIfBlank("", "NULL")    = "NULL"
+     * StringUtils.defaultIfBlank(" ", "NULL")   = "NULL"
+     * StringUtils.defaultIfBlank("bat", "NULL") = "bat"
+     * StringUtils.defaultIfBlank("", null)      = null
+     * 
+ * + * @param the specific kind of CharSequence. + * @param str the CharSequence to check, may be null. + * @param defaultStr the default CharSequence to return if {@code str} is {@link #isBlank(CharSequence) blank} (whitespaces, empty ({@code ""}), or + * {@code null}); may be null. + * @return the passed in CharSequence, or the default. + * @see StringUtils#defaultString(String, String) + * @see #isBlank(CharSequence) + */ + public static T defaultIfBlank(final T str, final T defaultStr) { + return isBlank(str) ? defaultStr : str; + } + + /** + * Returns either the passed in CharSequence, or if the CharSequence is empty or {@code null}, the value of {@code defaultStr}. + * + *
+     * StringUtils.defaultIfEmpty(null, "NULL")  = "NULL"
+     * StringUtils.defaultIfEmpty("", "NULL")    = "NULL"
+     * StringUtils.defaultIfEmpty(" ", "NULL")   = " "
+     * StringUtils.defaultIfEmpty("bat", "NULL") = "bat"
+     * StringUtils.defaultIfEmpty("", null)      = null
+     * 
+ * + * @param the specific kind of CharSequence. + * @param str the CharSequence to check, may be null. + * @param defaultStr the default CharSequence to return if the input is empty ("") or {@code null}, may be null. + * @return the passed in CharSequence, or the default. + * @see StringUtils#defaultString(String, String) + */ + public static T defaultIfEmpty(final T str, final T defaultStr) { + return isEmpty(str) ? defaultStr : str; + } + + /** + * Returns either the passed in String, or if the String is {@code null}, an empty String (""). + * + *
+     * StringUtils.defaultString(null)  = ""
+     * StringUtils.defaultString("")    = ""
+     * StringUtils.defaultString("bat") = "bat"
+     * 
+ * + * @param str the String to check, may be null. + * @return the passed in String, or the empty String if it was {@code null}. + * @see Objects#toString(Object, String) + * @see String#valueOf(Object) + */ + public static String defaultString(final String str) { + return Objects.toString(str, EMPTY); + } + + /** + * Returns either the given String, or if the String is {@code null}, {@code nullDefault}. + * + *
+     * StringUtils.defaultString(null, "NULL")  = "NULL"
+     * StringUtils.defaultString("", "NULL")    = ""
+     * StringUtils.defaultString("bat", "NULL") = "bat"
+     * 
+ *

+ * Since this is now provided by Java, instead call {@link Objects#toString(Object, String)}: + *

+ * + *
+     * Objects.toString(null, "NULL")  = "NULL"
+     * Objects.toString("", "NULL")    = ""
+     * Objects.toString("bat", "NULL") = "bat"
+     * 
+ * + * @param str the String to check, may be null. + * @param nullDefault the default String to return if the input is {@code null}, may be null. + * @return the passed in String, or the default if it was {@code null}. + * @see Objects#toString(Object, String) + * @see String#valueOf(Object) + * @deprecated Use {@link Objects#toString(Object, String)}. + */ + @Deprecated + public static String defaultString(final String str, final String nullDefault) { + return Objects.toString(str, nullDefault); + } + + /** + * Deletes all whitespaces from a String as defined by {@link Character#isWhitespace(char)}. + * + *
+     * StringUtils.deleteWhitespace(null)         = null
+     * StringUtils.deleteWhitespace("")           = ""
+     * StringUtils.deleteWhitespace("abc")        = "abc"
+     * StringUtils.deleteWhitespace("   ab  c  ") = "abc"
+     * 
+ * + * @param str the String to delete whitespace from, may be null. + * @return the String without whitespaces, {@code null} if null String input. + */ + public static String deleteWhitespace(final String str) { + if (isEmpty(str)) { + return str; + } + final int sz = str.length(); + final char[] chs = new char[sz]; + int count = 0; + for (int i = 0; i < sz; i++) { + if (!Character.isWhitespace(str.charAt(i))) { + chs[count++] = str.charAt(i); + } + } + if (count == sz) { + return str; + } + if (count == 0) { + return EMPTY; + } + return new String(chs, 0, count); + } + + /** + * Compares two Strings, and returns the portion where they differ. More precisely, return the remainder of the second String, starting from where it's + * different from the first. This means that the difference between "abc" and "ab" is the empty String and not "c". + * + *

+ * For example, {@code difference("i am a machine", "i am a robot") -> "robot"}. + *

+ * + *
+     * StringUtils.difference(null, null)       = null
+     * StringUtils.difference("", "")           = ""
+     * StringUtils.difference("", "abc")        = "abc"
+     * StringUtils.difference("abc", "")        = ""
+     * StringUtils.difference("abc", "abc")     = ""
+     * StringUtils.difference("abc", "ab")      = ""
+     * StringUtils.difference("ab", "abxyz")    = "xyz"
+     * StringUtils.difference("abcde", "abxyz") = "xyz"
+     * StringUtils.difference("abcde", "xyz")   = "xyz"
+     * 
+ * + * @param str1 the first String, may be null. + * @param str2 the second String, may be null. + * @return the portion of str2 where it differs from str1; returns the empty String if they are equal. + * @see #indexOfDifference(CharSequence,CharSequence) + * @since 2.0 + */ + public static String difference(final String str1, final String str2) { + if (str1 == null) { + return str2; + } + if (str2 == null) { + return str1; + } + final int at = indexOfDifference(str1, str2); + if (at == INDEX_NOT_FOUND) { + return EMPTY; + } + return str2.substring(at); + } + + /** + * Tests if a CharSequence ends with a specified suffix. + * + *

+ * {@code null}s are handled without exceptions. Two {@code null} references are considered to be equal. The comparison is case-sensitive. + *

+ * + *
+     * StringUtils.endsWith(null, null)      = true
+     * StringUtils.endsWith(null, "def")     = false
+     * StringUtils.endsWith("abcdef", null)  = false
+     * StringUtils.endsWith("abcdef", "def") = true
+     * StringUtils.endsWith("ABCDEF", "def") = false
+     * StringUtils.endsWith("ABCDEF", "cde") = false
+     * StringUtils.endsWith("ABCDEF", "")    = true
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param suffix the suffix to find, may be null. + * @return {@code true} if the CharSequence ends with the suffix, case-sensitive, or both {@code null}. + * @see String#endsWith(String) + * @since 2.4 + * @since 3.0 Changed signature from endsWith(String, String) to endsWith(CharSequence, CharSequence) + * @deprecated Use {@link Strings#endsWith(CharSequence, CharSequence) Strings.CS.endsWith(CharSequence, CharSequence)}. + */ + @Deprecated + public static boolean endsWith(final CharSequence str, final CharSequence suffix) { + return Strings.CS.endsWith(str, suffix); + } + + /** + * Tests if a CharSequence ends with any of the provided case-sensitive suffixes. + * + *
+     * StringUtils.endsWithAny(null, null)                  = false
+     * StringUtils.endsWithAny(null, new String[] {"abc"})  = false
+     * StringUtils.endsWithAny("abcxyz", null)              = false
+     * StringUtils.endsWithAny("abcxyz", new String[] {""}) = true
+     * StringUtils.endsWithAny("abcxyz", new String[] {"xyz"}) = true
+     * StringUtils.endsWithAny("abcxyz", new String[] {null, "xyz", "abc"}) = true
+     * StringUtils.endsWithAny("abcXYZ", "def", "XYZ")      = true
+     * StringUtils.endsWithAny("abcXYZ", "def", "xyz")      = false
+     * 
+ * + * @param sequence the CharSequence to check, may be null. + * @param searchStrings the case-sensitive CharSequences to find, may be empty or contain {@code null}. + * @return {@code true} if the input {@code sequence} is {@code null} AND no {@code searchStrings} are provided, or the input {@code sequence} ends in any + * of the provided case-sensitive {@code searchStrings}. + * @see StringUtils#endsWith(CharSequence, CharSequence) + * @since 3.0 + * @deprecated Use {@link Strings#endsWithAny(CharSequence, CharSequence...) Strings.CS.endsWithAny(CharSequence, CharSequence...)}. + */ + @Deprecated + public static boolean endsWithAny(final CharSequence sequence, final CharSequence... searchStrings) { + return Strings.CS.endsWithAny(sequence, searchStrings); + } + + /** + * Case-insensitive check if a CharSequence ends with a specified suffix. + * + *

+ * {@code null}s are handled without exceptions. Two {@code null} references are considered to be equal. The comparison is case insensitive. + *

+ * + *
+     * StringUtils.endsWithIgnoreCase(null, null)      = true
+     * StringUtils.endsWithIgnoreCase(null, "def")     = false
+     * StringUtils.endsWithIgnoreCase("abcdef", null)  = false
+     * StringUtils.endsWithIgnoreCase("abcdef", "def") = true
+     * StringUtils.endsWithIgnoreCase("ABCDEF", "def") = true
+     * StringUtils.endsWithIgnoreCase("ABCDEF", "cde") = false
+     * 
+ * + * @param str the CharSequence to check, may be null + * @param suffix the suffix to find, may be null + * @return {@code true} if the CharSequence ends with the suffix, case-insensitive, or both {@code null} + * @see String#endsWith(String) + * @since 2.4 + * @since 3.0 Changed signature from endsWithIgnoreCase(String, String) to endsWithIgnoreCase(CharSequence, CharSequence) + * @deprecated Use {@link Strings#endsWith(CharSequence, CharSequence) Strings.CI.endsWith(CharSequence, CharSequence)}. + */ + @Deprecated + public static boolean endsWithIgnoreCase(final CharSequence str, final CharSequence suffix) { + return Strings.CI.endsWith(str, suffix); + } + + /** + * Compares two CharSequences, returning {@code true} if they represent equal sequences of characters. + * + *

+ * {@code null}s are handled without exceptions. Two {@code null} references are considered to be equal. The comparison is case-sensitive. + *

+ * + *
+     * StringUtils.equals(null, null)   = true
+     * StringUtils.equals(null, "abc")  = false
+     * StringUtils.equals("abc", null)  = false
+     * StringUtils.equals("abc", "abc") = true
+     * StringUtils.equals("abc", "ABC") = false
+     * 
+ * + * @param cs1 the first CharSequence, may be {@code null}. + * @param cs2 the second CharSequence, may be {@code null}. + * @return {@code true} if the CharSequences are equal (case-sensitive), or both {@code null}. + * @since 3.0 Changed signature from equals(String, String) to equals(CharSequence, CharSequence) + * @see Object#equals(Object) + * @see #equalsIgnoreCase(CharSequence, CharSequence) + * @deprecated Use {@link Strings#equals(CharSequence, CharSequence) Strings.CS.equals(CharSequence, CharSequence)}. + */ + @Deprecated + public static boolean equals(final CharSequence cs1, final CharSequence cs2) { + return Strings.CS.equals(cs1, cs2); + } + + /** + * Compares given {@code string} to a CharSequences vararg of {@code searchStrings}, returning {@code true} if the {@code string} is equal to any of the + * {@code searchStrings}. + * + *
+     * StringUtils.equalsAny(null, (CharSequence[]) null) = false
+     * StringUtils.equalsAny(null, null, null)    = true
+     * StringUtils.equalsAny(null, "abc", "def")  = false
+     * StringUtils.equalsAny("abc", null, "def")  = false
+     * StringUtils.equalsAny("abc", "abc", "def") = true
+     * StringUtils.equalsAny("abc", "ABC", "DEF") = false
+     * 
+ * + * @param string to compare, may be {@code null}. + * @param searchStrings a vararg of strings, may be {@code null}. + * @return {@code true} if the string is equal (case-sensitive) to any other element of {@code searchStrings}; {@code false} if {@code searchStrings} is + * null or contains no matches. + * @since 3.5 + * @deprecated Use {@link Strings#equalsAny(CharSequence, CharSequence...) Strings.CS.equalsAny(CharSequence, CharSequence...)}. + */ + @Deprecated + public static boolean equalsAny(final CharSequence string, final CharSequence... searchStrings) { + return Strings.CS.equalsAny(string, searchStrings); + } + + /** + * Compares given {@code string} to a CharSequences vararg of {@code searchStrings}, + * returning {@code true} if the {@code string} is equal to any of the {@code searchStrings}, ignoring case. + * + *
+     * StringUtils.equalsAnyIgnoreCase(null, (CharSequence[]) null) = false
+     * StringUtils.equalsAnyIgnoreCase(null, null, null)    = true
+     * StringUtils.equalsAnyIgnoreCase(null, "abc", "def")  = false
+     * StringUtils.equalsAnyIgnoreCase("abc", null, "def")  = false
+     * StringUtils.equalsAnyIgnoreCase("abc", "abc", "def") = true
+     * StringUtils.equalsAnyIgnoreCase("abc", "ABC", "DEF") = true
+     * 
+ * + * @param string to compare, may be {@code null}. + * @param searchStrings a vararg of strings, may be {@code null}. + * @return {@code true} if the string is equal (case-insensitive) to any other element of {@code searchStrings}; + * {@code false} if {@code searchStrings} is null or contains no matches. + * @since 3.5 + * @deprecated Use {@link Strings#equalsAny(CharSequence, CharSequence...) Strings.CI.equalsAny(CharSequence, CharSequence...)}. + */ + @Deprecated + public static boolean equalsAnyIgnoreCase(final CharSequence string, final CharSequence... searchStrings) { + return Strings.CI.equalsAny(string, searchStrings); + } + + /** + * Compares two CharSequences, returning {@code true} if they represent equal sequences of characters, ignoring case. + * + *

+ * {@code null}s are handled without exceptions. Two {@code null} references are considered equal. The comparison is case insensitive. + *

+ * + *
+     * StringUtils.equalsIgnoreCase(null, null)   = true
+     * StringUtils.equalsIgnoreCase(null, "abc")  = false
+     * StringUtils.equalsIgnoreCase("abc", null)  = false
+     * StringUtils.equalsIgnoreCase("abc", "abc") = true
+     * StringUtils.equalsIgnoreCase("abc", "ABC") = true
+     * 
+ * + * @param cs1 the first CharSequence, may be {@code null}. + * @param cs2 the second CharSequence, may be {@code null}. + * @return {@code true} if the CharSequences are equal (case-insensitive), or both {@code null}. + * @since 3.0 Changed signature from equalsIgnoreCase(String, String) to equalsIgnoreCase(CharSequence, CharSequence) + * @see #equals(CharSequence, CharSequence) + * @deprecated Use {@link Strings#equals(CharSequence, CharSequence) Strings.CI.equals(CharSequence, CharSequence)}. + */ + @Deprecated + public static boolean equalsIgnoreCase(final CharSequence cs1, final CharSequence cs2) { + return Strings.CI.equals(cs1, cs2); + } + + /** + * Returns the first value in the array which is not empty (""), {@code null} or whitespace only. + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *

+ * If all values are blank or the array is {@code null} or empty then {@code null} is returned. + *

+ * + *
+     * StringUtils.firstNonBlank(null, null, null)     = null
+     * StringUtils.firstNonBlank(null, "", " ")        = null
+     * StringUtils.firstNonBlank("abc")                = "abc"
+     * StringUtils.firstNonBlank(null, "xyz")          = "xyz"
+     * StringUtils.firstNonBlank(null, "", " ", "xyz") = "xyz"
+     * StringUtils.firstNonBlank(null, "xyz", "abc")   = "xyz"
+     * StringUtils.firstNonBlank()                     = null
+     * 
+ * + * @param the specific kind of CharSequence. + * @param values the values to test, may be {@code null} or empty. + * @return the first value from {@code values} which is not blank, or {@code null} if there are no non-blank values. + * @since 3.8 + */ + @SafeVarargs + public static T firstNonBlank(final T... values) { + if (values != null) { + for (final T val : values) { + if (isNotBlank(val)) { + return val; + } + } + } + return null; + } + + /** + * Returns the first value in the array which is not empty. + * + *

+ * If all values are empty or the array is {@code null} or empty then {@code null} is returned. + *

+ * + *
+     * StringUtils.firstNonEmpty(null, null, null)   = null
+     * StringUtils.firstNonEmpty(null, null, "")     = null
+     * StringUtils.firstNonEmpty(null, "", " ")      = " "
+     * StringUtils.firstNonEmpty("abc")              = "abc"
+     * StringUtils.firstNonEmpty(null, "xyz")        = "xyz"
+     * StringUtils.firstNonEmpty("", "xyz")          = "xyz"
+     * StringUtils.firstNonEmpty(null, "xyz", "abc") = "xyz"
+     * StringUtils.firstNonEmpty()                   = null
+     * 
+ * + * @param the specific kind of CharSequence. + * @param values the values to test, may be {@code null} or empty. + * @return the first value from {@code values} which is not empty, or {@code null} if there are no non-empty values. + * @since 3.8 + */ + @SafeVarargs + public static T firstNonEmpty(final T... values) { + if (values != null) { + for (final T val : values) { + if (isNotEmpty(val)) { + return val; + } + } + } + return null; + } + + /** + * Calls {@link String#getBytes(Charset)} in a null-safe manner. + * + * @param string input string. + * @param charset The {@link Charset} to encode the {@link String}. If null, then use the default Charset. + * @return The empty byte[] if {@code string} is null, the result of {@link String#getBytes(Charset)} otherwise. + * @see String#getBytes(Charset) + * @since 3.10 + */ + public static byte[] getBytes(final String string, final Charset charset) { + return string == null ? ArrayUtils.EMPTY_BYTE_ARRAY : string.getBytes(Charsets.toCharset(charset)); + } + + /** + * Calls {@link String#getBytes(String)} in a null-safe manner. + * + * @param string input string. + * @param charset The {@link Charset} name to encode the {@link String}. If null, then use the default Charset. + * @return The empty byte[] if {@code string} is null, the result of {@link String#getBytes(String)} otherwise. + * @throws UnsupportedEncodingException Thrown when the named charset is not supported. + * @see String#getBytes(String) + * @since 3.10 + */ + public static byte[] getBytes(final String string, final String charset) throws UnsupportedEncodingException { + return string == null ? ArrayUtils.EMPTY_BYTE_ARRAY : string.getBytes(Charsets.toCharsetName(charset)); + } + + /** + * Compares all Strings in an array and returns the initial sequence of characters that is common to all of them. + * + *

+ * For example, {@code getCommonPrefix("i am a machine", "i am a robot") -> "i am a "} + *

+ * + *
+     * StringUtils.getCommonPrefix(null)                             = ""
+     * StringUtils.getCommonPrefix(new String[] {})                  = ""
+     * StringUtils.getCommonPrefix(new String[] {"abc"})             = "abc"
+     * StringUtils.getCommonPrefix(new String[] {null, null})        = ""
+     * StringUtils.getCommonPrefix(new String[] {"", ""})            = ""
+     * StringUtils.getCommonPrefix(new String[] {"", null})          = ""
+     * StringUtils.getCommonPrefix(new String[] {"abc", null, null}) = ""
+     * StringUtils.getCommonPrefix(new String[] {null, null, "abc"}) = ""
+     * StringUtils.getCommonPrefix(new String[] {"", "abc"})         = ""
+     * StringUtils.getCommonPrefix(new String[] {"abc", ""})         = ""
+     * StringUtils.getCommonPrefix(new String[] {"abc", "abc"})      = "abc"
+     * StringUtils.getCommonPrefix(new String[] {"abc", "a"})        = "a"
+     * StringUtils.getCommonPrefix(new String[] {"ab", "abxyz"})     = "ab"
+     * StringUtils.getCommonPrefix(new String[] {"abcde", "abxyz"})  = "ab"
+     * StringUtils.getCommonPrefix(new String[] {"abcde", "xyz"})    = ""
+     * StringUtils.getCommonPrefix(new String[] {"xyz", "abcde"})    = ""
+     * StringUtils.getCommonPrefix(new String[] {"i am a machine", "i am a robot"}) = "i am a "
+     * 
+ * + * @param strs array of String objects, entries may be null. + * @return the initial sequence of characters that are common to all Strings in the array; empty String if the array is null, the elements are all null or + * if there is no common prefix. + * @since 2.4 + */ + public static String getCommonPrefix(final String... strs) { + if (ArrayUtils.isEmpty(strs)) { + return EMPTY; + } + final int smallestIndexOfDiff = indexOfDifference(strs); + if (smallestIndexOfDiff == INDEX_NOT_FOUND) { + // all strings were identical + if (strs[0] == null) { + return EMPTY; + } + return strs[0]; + } + if (smallestIndexOfDiff == 0) { + // there were no common initial characters + return EMPTY; + } + // we found a common initial character sequence + return strs[0].substring(0, smallestIndexOfDiff); + } + + /** + * Checks if a String {@code str} contains Unicode digits, if yes then concatenate all the digits in {@code str} and return it as a String. + * + *

+ * An empty ("") String will be returned if no digits found in {@code str}. + *

+ * + *
+     * StringUtils.getDigits(null)                 = null
+     * StringUtils.getDigits("")                   = ""
+     * StringUtils.getDigits("abc")                = ""
+     * StringUtils.getDigits("1000$")              = "1000"
+     * StringUtils.getDigits("1123~45")            = "112345"
+     * StringUtils.getDigits("(541) 754-3010")     = "5417543010"
+     * StringUtils.getDigits("\u0967\u0968\u0969") = "\u0967\u0968\u0969"
+     * 
+ * + * @param str the String to extract digits from, may be null. + * @return String with only digits, or an empty ("") String if no digits found, or {@code null} String if {@code str} is null. + * @since 3.6 + */ + public static String getDigits(final String str) { + if (isEmpty(str)) { + return str; + } + final int len = str.length(); + final char[] buffer = new char[len]; + int count = 0; + + for (int i = 0; i < len; i++) { + final char tempChar = str.charAt(i); + if (Character.isDigit(tempChar)) { + buffer[count++] = tempChar; + } + } + return new String(buffer, 0, count); + } + + /** + * Gets the Fuzzy Distance which indicates the similarity score between two Strings. + * + *

+ * This string matching algorithm is similar to the algorithms of editors such as Sublime Text, TextMate, Atom and others. One point is given for every + * matched character. Subsequent matches yield two bonus points. A higher score indicates a higher similarity. + *

+ * + *
+     * StringUtils.getFuzzyDistance(null, null, null)                                    = Throws {@link IllegalArgumentException}
+     * StringUtils.getFuzzyDistance("", "", Locale.ENGLISH)                              = 0
+     * StringUtils.getFuzzyDistance("Workshop", "b", Locale.ENGLISH)                     = 0
+     * StringUtils.getFuzzyDistance("Room", "o", Locale.ENGLISH)                         = 1
+     * StringUtils.getFuzzyDistance("Workshop", "w", Locale.ENGLISH)                     = 1
+     * StringUtils.getFuzzyDistance("Workshop", "ws", Locale.ENGLISH)                    = 2
+     * StringUtils.getFuzzyDistance("Workshop", "wo", Locale.ENGLISH)                    = 4
+     * StringUtils.getFuzzyDistance("Apache Software Foundation", "asf", Locale.ENGLISH) = 3
+     * 
+ * + * @param term a full term that should be matched against, must not be null. + * @param query the query that will be matched against a term, must not be null. + * @param locale This string matching logic is case-insensitive. A locale is necessary to normalize both Strings to lower case. + * @return result score. + * @throws IllegalArgumentException if either String input {@code null} or Locale input {@code null}. + * @since 3.4 + * @deprecated As of 3.6, use Apache Commons Text + * + * FuzzyScore instead. + */ + @Deprecated + public static int getFuzzyDistance(final CharSequence term, final CharSequence query, final Locale locale) { + if (term == null || query == null) { + throw new IllegalArgumentException("Strings must not be null"); + } + if (locale == null) { + throw new IllegalArgumentException("Locale must not be null"); + } + // fuzzy logic is case-insensitive. We normalize the Strings to lower + // case right from the start. Turning characters to lower case + // via Character.toLowerCase(char) is unfortunately insufficient + // as it does not accept a locale. + final String termLowerCase = term.toString().toLowerCase(locale); + final String queryLowerCase = query.toString().toLowerCase(locale); + // the resulting score + int score = 0; + // the position in the term which will be scanned next for potential + // query character matches + int termIndex = 0; + // index of the previously matched character in the term + int previousMatchingCharacterIndex = Integer.MIN_VALUE; + for (int queryIndex = 0; queryIndex < queryLowerCase.length(); queryIndex++) { + final char queryChar = queryLowerCase.charAt(queryIndex); + boolean termCharacterMatchFound = false; + for (; termIndex < termLowerCase.length() && !termCharacterMatchFound; termIndex++) { + final char termChar = termLowerCase.charAt(termIndex); + if (queryChar == termChar) { + // simple character matches result in one point + score++; + // subsequent character matches further improve + // the score. + if (previousMatchingCharacterIndex + 1 == termIndex) { + score += 2; + } + previousMatchingCharacterIndex = termIndex; + // we can leave the nested loop. Every character in the + // query can match at most one character in the term. + termCharacterMatchFound = true; + } + } + } + return score; + } + + /** + * Returns either the passed in CharSequence, or if the CharSequence is {@link #isBlank(CharSequence) blank} (whitespaces, empty ({@code ""}), or + * {@code null}), the value supplied by {@code defaultStrSupplier}. + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *

+ * Caller responsible for thread-safety and exception handling of default value supplier + *

+ * + *
+     * {@code
+     * StringUtils.getIfBlank(null, () -> "NULL")   = "NULL"
+     * StringUtils.getIfBlank("", () -> "NULL")     = "NULL"
+     * StringUtils.getIfBlank(" ", () -> "NULL")    = "NULL"
+     * StringUtils.getIfBlank("bat", () -> "NULL")  = "bat"
+     * StringUtils.getIfBlank("", () -> null)       = null
+     * StringUtils.getIfBlank("", null)             = null
+     * }
+ * + * @param the specific kind of CharSequence. + * @param str the CharSequence to check, may be null. + * @param defaultSupplier the supplier of default CharSequence to return if the input is {@link #isBlank(CharSequence) blank} (whitespaces, empty + * ({@code ""}), or {@code null}); may be null. + * @return the passed in CharSequence, or the default + * @see StringUtils#defaultString(String, String) + * @see #isBlank(CharSequence) + * @since 3.10 + */ + public static T getIfBlank(final T str, final Supplier defaultSupplier) { + return isBlank(str) ? Suppliers.get(defaultSupplier) : str; + } + + /** + * Returns either the passed in CharSequence, or if the CharSequence is empty or {@code null}, the value supplied by {@code defaultStrSupplier}. + * + *

+ * Caller responsible for thread-safety and exception handling of default value supplier + *

+ * + *
+     * {@code
+     * StringUtils.getIfEmpty(null, () -> "NULL")    = "NULL"
+     * StringUtils.getIfEmpty("", () -> "NULL")      = "NULL"
+     * StringUtils.getIfEmpty(" ", () -> "NULL")     = " "
+     * StringUtils.getIfEmpty("bat", () -> "NULL")   = "bat"
+     * StringUtils.getIfEmpty("", () -> null)        = null
+     * StringUtils.getIfEmpty("", null)              = null
+     * }
+     * 
+ * + * @param the specific kind of CharSequence. + * @param str the CharSequence to check, may be null. + * @param defaultSupplier the supplier of default CharSequence to return if the input is empty ("") or {@code null}, may be null. + * @return the passed in CharSequence, or the default. + * @see StringUtils#defaultString(String, String) + * @since 3.10 + */ + public static T getIfEmpty(final T str, final Supplier defaultSupplier) { + return isEmpty(str) ? Suppliers.get(defaultSupplier) : str; + } + + /** + * Gets the Jaro Winkler Distance which indicates the similarity score between two Strings. + * + *

+ * The Jaro measure is the weighted sum of percentage of matched characters from each file and transposed characters. Winkler increased this measure for + * matching initial characters. + *

+ * + *

+ * This implementation is based on the Jaro Winkler similarity algorithm from + * https://en.wikipedia.org/wiki/Jaro%E2%80%93Winkler_distance. + *

+ * + *
+     * StringUtils.getJaroWinklerDistance(null, null)          = Throws {@link IllegalArgumentException}
+     * StringUtils.getJaroWinklerDistance("", "")              = 0.0
+     * StringUtils.getJaroWinklerDistance("", "a")             = 0.0
+     * StringUtils.getJaroWinklerDistance("aaapppp", "")       = 0.0
+     * StringUtils.getJaroWinklerDistance("frog", "fog")       = 0.93
+     * StringUtils.getJaroWinklerDistance("fly", "ant")        = 0.0
+     * StringUtils.getJaroWinklerDistance("elephant", "hippo") = 0.44
+     * StringUtils.getJaroWinklerDistance("hippo", "elephant") = 0.44
+     * StringUtils.getJaroWinklerDistance("hippo", "zzzzzzzz") = 0.0
+     * StringUtils.getJaroWinklerDistance("hello", "hallo")    = 0.88
+     * StringUtils.getJaroWinklerDistance("ABC Corporation", "ABC Corp") = 0.93
+     * StringUtils.getJaroWinklerDistance("D N H Enterprises Inc", "D & H Enterprises, Inc.") = 0.95
+     * StringUtils.getJaroWinklerDistance("My Gym Children's Fitness Center", "My Gym. Childrens Fitness") = 0.92
+     * StringUtils.getJaroWinklerDistance("PENNSYLVANIA", "PENNCISYLVNIA") = 0.88
+     * 
+ * + * @param first the first String, must not be null. + * @param second the second String, must not be null. + * @return result distance. + * @throws IllegalArgumentException if either String input {@code null}. + * @since 3.3 + * @deprecated As of 3.6, use Apache Commons Text + * + * JaroWinklerDistance instead. + */ + @Deprecated + public static double getJaroWinklerDistance(final CharSequence first, final CharSequence second) { + final double DEFAULT_SCALING_FACTOR = 0.1; + + if (first == null || second == null) { + throw new IllegalArgumentException("Strings must not be null"); + } + + final int[] mtp = matches(first, second); + final double m = mtp[0]; + if (m == 0) { + return 0D; + } + final double j = (m / first.length() + m / second.length() + (m - mtp[1]) / m) / 3; + final double jw = j < 0.7D ? j : j + Math.min(DEFAULT_SCALING_FACTOR, 1D / mtp[3]) * mtp[2] * (1D - j); + return Math.round(jw * 100.0D) / 100.0D; + } + + /** + * Gets the Levenshtein distance between two Strings. + * + *

+ * This is the number of changes needed to change one String into another, where each change is a single character modification (deletion, insertion or + * substitution). + *

+ * + *

+ * The implementation uses a single-dimensional array of length s.length() + 1. See + * + * https://blog.softwx.net/2014/12/optimizing-levenshtein-algorithm-in-c.html for details. + *

+ * + *
+     * StringUtils.getLevenshteinDistance(null, *)             = Throws {@link IllegalArgumentException}
+     * StringUtils.getLevenshteinDistance(*, null)             = Throws {@link IllegalArgumentException}
+     * StringUtils.getLevenshteinDistance("", "")              = 0
+     * StringUtils.getLevenshteinDistance("", "a")             = 1
+     * StringUtils.getLevenshteinDistance("aaapppp", "")       = 7
+     * StringUtils.getLevenshteinDistance("frog", "fog")       = 1
+     * StringUtils.getLevenshteinDistance("fly", "ant")        = 3
+     * StringUtils.getLevenshteinDistance("elephant", "hippo") = 7
+     * StringUtils.getLevenshteinDistance("hippo", "elephant") = 7
+     * StringUtils.getLevenshteinDistance("hippo", "zzzzzzzz") = 8
+     * StringUtils.getLevenshteinDistance("hello", "hallo")    = 1
+     * 
+ * + * @param s the first String, must not be null. + * @param t the second String, must not be null. + * @return result distance. + * @throws IllegalArgumentException if either String input {@code null}. + * @since 3.0 Changed signature from getLevenshteinDistance(String, String) to getLevenshteinDistance(CharSequence, CharSequence) + * @deprecated As of 3.6, use Apache Commons Text + * + * LevenshteinDistance instead. + */ + @Deprecated + public static int getLevenshteinDistance(CharSequence s, CharSequence t) { + if (s == null || t == null) { + throw new IllegalArgumentException("Strings must not be null"); + } + + int n = s.length(); + int m = t.length(); + + if (n == 0) { + return m; + } + if (m == 0) { + return n; + } + + if (n > m) { + // swap the input strings to consume less memory + final CharSequence tmp = s; + s = t; + t = tmp; + n = m; + m = t.length(); + } + + final int[] p = new int[n + 1]; + // indexes into strings s and t + int i; // iterates through s + int j; // iterates through t + int upperleft; + int upper; + + char jOfT; // jth character of t + int cost; + + for (i = 0; i <= n; i++) { + p[i] = i; + } + + for (j = 1; j <= m; j++) { + upperleft = p[0]; + jOfT = t.charAt(j - 1); + p[0] = j; + + for (i = 1; i <= n; i++) { + upper = p[i]; + cost = s.charAt(i - 1) == jOfT ? 0 : 1; + // minimum of cell to the left+1, to the top+1, diagonally left and up +cost + p[i] = Math.min(Math.min(p[i - 1] + 1, p[i] + 1), upperleft + cost); + upperleft = upper; + } + } + + return p[n]; + } + + /** + * Gets the Levenshtein distance between two Strings if it's less than or equal to a given threshold. + * + *

+ * This is the number of changes needed to change one String into another, where each change is a single character modification (deletion, insertion or + * substitution). + *

+ * + *

+ * This implementation follows from Algorithms on Strings, Trees and Sequences by Dan Gusfield and Chas Emerick's implementation of the Levenshtein distance + * algorithm. + *

+ * + *
+     * StringUtils.getLevenshteinDistance(null, *, *)             = Throws {@link IllegalArgumentException}
+     * StringUtils.getLevenshteinDistance(*, null, *)             = Throws {@link IllegalArgumentException}
+     * StringUtils.getLevenshteinDistance(*, *, -1)               = Throws {@link IllegalArgumentException}
+     * StringUtils.getLevenshteinDistance("", "", 0)              = 0
+     * StringUtils.getLevenshteinDistance("aaapppp", "", 8)       = 7
+     * StringUtils.getLevenshteinDistance("aaapppp", "", 7)       = 7
+     * StringUtils.getLevenshteinDistance("aaapppp", "", 6))      = -1
+     * StringUtils.getLevenshteinDistance("elephant", "hippo", 7) = 7
+     * StringUtils.getLevenshteinDistance("elephant", "hippo", 6) = -1
+     * StringUtils.getLevenshteinDistance("hippo", "elephant", 7) = 7
+     * StringUtils.getLevenshteinDistance("hippo", "elephant", 6) = -1
+     * 
+ * + * @param s the first String, must not be null. + * @param t the second String, must not be null. + * @param threshold the target threshold, must not be negative. + * @return result distance, or {@code -1} if the distance would be greater than the threshold. + * @throws IllegalArgumentException if either String input {@code null} or negative threshold. + * @deprecated As of 3.6, use Apache Commons Text + * + * LevenshteinDistance instead. + */ + @Deprecated + public static int getLevenshteinDistance(CharSequence s, CharSequence t, final int threshold) { + if (s == null || t == null) { + throw new IllegalArgumentException("Strings must not be null"); + } + if (threshold < 0) { + throw new IllegalArgumentException("Threshold must not be negative"); + } + + /* + This implementation only computes the distance if it's less than or equal to the + threshold value, returning -1 if it's greater. The advantage is performance: unbounded + distance is O(nm), but a bound of k allows us to reduce it to O(km) time by only + computing a diagonal stripe of width 2k + 1 of the cost table. + It is also possible to use this to compute the unbounded Levenshtein distance by starting + the threshold at 1 and doubling each time until the distance is found; this is O(dm), where + d is the distance. + + One subtlety comes from needing to ignore entries on the border of our stripe + for example, + p[] = |#|#|#|* + d[] = *|#|#|#| + We must ignore the entry to the left of the leftmost member + We must ignore the entry above the rightmost member + + Another subtlety comes from our stripe running off the matrix if the strings aren't + of the same size. Since string s is always swapped to be the shorter of the two, + the stripe will always run off to the upper right instead of the lower left of the matrix. + + As a concrete example, suppose s is of length 5, t is of length 7, and our threshold is 1. + In this case we're going to walk a stripe of length 3. The matrix would look like so: + + 1 2 3 4 5 + 1 |#|#| | | | + 2 |#|#|#| | | + 3 | |#|#|#| | + 4 | | |#|#|#| + 5 | | | |#|#| + 6 | | | | |#| + 7 | | | | | | + + Note how the stripe leads off the table as there is no possible way to turn a string of length 5 + into one of length 7 in edit distance of 1. + + Additionally, this implementation decreases memory usage by using two + single-dimensional arrays and swapping them back and forth instead of allocating + an entire n by m matrix. This requires a few minor changes, such as immediately returning + when it's detected that the stripe has run off the matrix and initially filling the arrays with + large values so that entries we don't compute are ignored. + + See Algorithms on Strings, Trees and Sequences by Dan Gusfield for some discussion. + */ + + int n = s.length(); // length of s + int m = t.length(); // length of t + + // if one string is empty, the edit distance is necessarily the length of the other + if (n == 0) { + return m <= threshold ? m : -1; + } + if (m == 0) { + return n <= threshold ? n : -1; + } + if (Math.abs(n - m) > threshold) { + // no need to calculate the distance if the length difference is greater than the threshold + return -1; + } + + if (n > m) { + // swap the two strings to consume less memory + final CharSequence tmp = s; + s = t; + t = tmp; + n = m; + m = t.length(); + } + + int[] p = new int[n + 1]; // 'previous' cost array, horizontally + int[] d = new int[n + 1]; // cost array, horizontally + int[] tmp; // placeholder to assist in swapping p and d + + // fill in starting table values + final int boundary = Math.min(n, threshold) + 1; + for (int i = 0; i < boundary; i++) { + p[i] = i; + } + // these fills ensure that the value above the rightmost entry of our + // stripe will be ignored in following loop iterations + Arrays.fill(p, boundary, p.length, Integer.MAX_VALUE); + Arrays.fill(d, Integer.MAX_VALUE); + + // iterates through t + for (int j = 1; j <= m; j++) { + final char jOfT = t.charAt(j - 1); // jth character of t + d[0] = j; + + // compute stripe indices, constrain to array size + final int min = Math.max(1, j - threshold); + final int max = j > Integer.MAX_VALUE - threshold ? n : Math.min(n, j + threshold); + + // the stripe may lead off of the table if s and t are of different sizes + if (min > max) { + return -1; + } + + // ignore entry left of leftmost + if (min > 1) { + d[min - 1] = Integer.MAX_VALUE; + } + + // iterates through [min, max] in s + for (int i = min; i <= max; i++) { + if (s.charAt(i - 1) == jOfT) { + // diagonally left and up + d[i] = p[i - 1]; + } else { + // 1 + minimum of cell to the left, to the top, diagonally left and up + d[i] = 1 + Math.min(Math.min(d[i - 1], p[i]), p[i - 1]); + } + } + + // copy current distance counts to 'previous row' distance counts + tmp = p; + p = d; + d = tmp; + } + + // if p[n] is greater than the threshold, there's no guarantee on it being the correct + // distance + if (p[n] <= threshold) { + return p[n]; + } + return -1; + } + + /** + * Finds the first index within a CharSequence, handling {@code null}. This method uses {@link String#indexOf(String, int)} if possible. + * + *

+ * A {@code null} CharSequence will return {@code -1}. + *

+ * + *
+     * StringUtils.indexOf(null, *)          = -1
+     * StringUtils.indexOf(*, null)          = -1
+     * StringUtils.indexOf("", "")           = 0
+     * StringUtils.indexOf("", *)            = -1 (except when * = "")
+     * StringUtils.indexOf("aabaabaa", "a")  = 0
+     * StringUtils.indexOf("aabaabaa", "b")  = 2
+     * StringUtils.indexOf("aabaabaa", "ab") = 1
+     * StringUtils.indexOf("aabaabaa", "")   = 0
+     * 
+ * + * @param seq the CharSequence to check, may be null. + * @param searchSeq the CharSequence to find, may be null. + * @return the first index of the search CharSequence, -1 if no match or {@code null} string input. + * @since 2.0 + * @since 3.0 Changed signature from indexOf(String, String) to indexOf(CharSequence, CharSequence) + * @deprecated Use {@link Strings#indexOf(CharSequence, CharSequence) Strings.CS.indexOf(CharSequence, CharSequence)}. + */ + @Deprecated + public static int indexOf(final CharSequence seq, final CharSequence searchSeq) { + return Strings.CS.indexOf(seq, searchSeq); + } + + /** + * Finds the first index within a CharSequence, handling {@code null}. This method uses {@link String#indexOf(String, int)} if possible. + * + *

+ * A {@code null} CharSequence will return {@code -1}. A negative start position is treated as zero. An empty ("") search CharSequence always matches. A + * start position greater than the string length only matches an empty search CharSequence. + *

+ * + *
+     * StringUtils.indexOf(null, *, *)          = -1
+     * StringUtils.indexOf(*, null, *)          = -1
+     * StringUtils.indexOf("", "", 0)           = 0
+     * StringUtils.indexOf("", *, 0)            = -1 (except when * = "")
+     * StringUtils.indexOf("aabaabaa", "a", 0)  = 0
+     * StringUtils.indexOf("aabaabaa", "b", 0)  = 2
+     * StringUtils.indexOf("aabaabaa", "ab", 0) = 1
+     * StringUtils.indexOf("aabaabaa", "b", 3)  = 5
+     * StringUtils.indexOf("aabaabaa", "b", 9)  = -1
+     * StringUtils.indexOf("aabaabaa", "b", -1) = 2
+     * StringUtils.indexOf("aabaabaa", "", 2)   = 2
+     * StringUtils.indexOf("abc", "", 9)        = 3
+     * 
+ * + * @param seq the CharSequence to check, may be null. + * @param searchSeq the CharSequence to find, may be null. + * @param startPos the start position, negative treated as zero. + * @return the first index of the search CharSequence (always ≥ startPos), -1 if no match or {@code null} string input. + * @since 2.0 + * @since 3.0 Changed signature from indexOf(String, String, int) to indexOf(CharSequence, CharSequence, int) + * @deprecated Use {@link Strings#indexOf(CharSequence, CharSequence, int) Strings.CS.indexOf(CharSequence, CharSequence, int)}. + */ + @Deprecated + public static int indexOf(final CharSequence seq, final CharSequence searchSeq, final int startPos) { + return Strings.CS.indexOf(seq, searchSeq, startPos); + } + + /** + * Returns the index within {@code seq} of the first occurrence of the specified character. If a character with value {@code searchChar} occurs in the + * character sequence represented by {@code seq} {@link CharSequence} object, then the index (in Unicode code units) of the first such occurrence is + * returned. For values of {@code searchChar} in the range from 0 to 0xFFFF (inclusive), this is the smallest value k such that: + * + *
+     * this.charAt(k) == searchChar
+     * 
+ * + *

+ * is true. For other values of {@code searchChar}, it is the smallest value k such that: + *

+ * + *
+     * this.codePointAt(k) == searchChar
+     * 
+ * + *

+ * is true. In either case, if no such character occurs in {@code seq}, then {@code INDEX_NOT_FOUND (-1)} is returned. + *

+ * + *

+ * Furthermore, a {@code null} or empty ("") CharSequence will return {@code INDEX_NOT_FOUND (-1)}. + *

+ * + *
+     * StringUtils.indexOf(null, *)         = -1
+     * StringUtils.indexOf("", *)           = -1
+     * StringUtils.indexOf("aabaabaa", 'a') = 0
+     * StringUtils.indexOf("aabaabaa", 'b') = 2
+     * StringUtils.indexOf("aaaaaaaa", 'Z') = -1
+     * 
+ * + * @param seq the CharSequence to check, may be null. + * @param searchChar the character to find. + * @return the first index of the search character, -1 if no match or {@code null} string input. + * @since 2.0 + * @since 3.0 Changed signature from indexOf(String, int) to indexOf(CharSequence, int) + * @since 3.6 Updated {@link CharSequenceUtils} call to behave more like {@link String} + */ + public static int indexOf(final CharSequence seq, final int searchChar) { + if (isEmpty(seq)) { + return INDEX_NOT_FOUND; + } + return CharSequenceUtils.indexOf(seq, searchChar, 0); + } + + /** + * Returns the index within {@code seq} of the first occurrence of the specified character, starting the search at the specified index. + *

+ * If a character with value {@code searchChar} occurs in the character sequence represented by the {@code seq} {@link CharSequence} object at an index no + * smaller than {@code startPos}, then the index of the first such occurrence is returned. For values of {@code searchChar} in the range from 0 to 0xFFFF + * (inclusive), this is the smallest value k such that: + *

+ * + *
+     * (this.charAt(k) == searchChar) && (k >= startPos)
+     * 
+ * + *

+ * is true. For other values of {@code searchChar}, it is the smallest value k such that: + *

+ * + *
+     * (this.codePointAt(k) == searchChar) && (k >= startPos)
+     * 
+ * + *

+ * is true. In either case, if no such character occurs in {@code seq} at or after position {@code startPos}, then {@code -1} is returned. + *

+ * + *

+ * There is no restriction on the value of {@code startPos}. If it is negative, it has the same effect as if it were zero: this entire string may be + * searched. If it is greater than the length of this string, it has the same effect as if it were equal to the length of this string: + * {@code (INDEX_NOT_FOUND) -1} is returned. Furthermore, a {@code null} or empty ("") CharSequence will return {@code (INDEX_NOT_FOUND) -1}. + *

+ *

+ * All indices are specified in {@code char} values (Unicode code units). + *

+ * + *
+     * StringUtils.indexOf(null, *, *)          = -1
+     * StringUtils.indexOf("", *, *)            = -1
+     * StringUtils.indexOf("aabaabaa", 'b', 0)  = 2
+     * StringUtils.indexOf("aabaabaa", 'b', 3)  = 5
+     * StringUtils.indexOf("aabaabaa", 'b', 9)  = -1
+     * StringUtils.indexOf("aabaabaa", 'b', -1) = 2
+     * 
+ * + * @param seq the CharSequence to check, may be null. + * @param searchChar the character to find. + * @param startPos the start position, negative treated as zero. + * @return the first index of the search character (always ≥ startPos), -1 if no match or {@code null} string input. + * @since 2.0 + * @since 3.0 Changed signature from indexOf(String, int, int) to indexOf(CharSequence, int, int) + * @since 3.6 Updated {@link CharSequenceUtils} call to behave more like {@link String} + */ + public static int indexOf(final CharSequence seq, final int searchChar, final int startPos) { + if (isEmpty(seq)) { + return INDEX_NOT_FOUND; + } + return CharSequenceUtils.indexOf(seq, searchChar, startPos); + } + + /** + * Search a CharSequence to find the first index of any character in the given set of characters. + * + *

+ * A {@code null} String will return {@code -1}. A {@code null} or zero length search array will return {@code -1}. + *

+ * + *
+     * StringUtils.indexOfAny(null, *)                  = -1
+     * StringUtils.indexOfAny("", *)                    = -1
+     * StringUtils.indexOfAny(*, null)                  = -1
+     * StringUtils.indexOfAny(*, [])                    = -1
+     * StringUtils.indexOfAny("zzabyycdxx", 'z', 'a')   = 0
+     * StringUtils.indexOfAny("zzabyycdxx", 'b', 'y')   = 3
+     * StringUtils.indexOfAny("aba", 'z')               = -1
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param searchChars the chars to search for, may be null. + * @return the index of any of the chars, -1 if no match or null input. + * @since 2.0 + * @since 3.0 Changed signature from indexOfAny(String, char[]) to indexOfAny(CharSequence, char...) + */ + public static int indexOfAny(final CharSequence cs, final char... searchChars) { + return indexOfAny(cs, 0, searchChars); + } + + /** + * Find the first index of any of a set of potential substrings. + * + *

+ * A {@code null} CharSequence will return {@code -1}. A {@code null} or zero length search array will return {@code -1}. A {@code null} search array entry + * will be ignored, but a search array containing "" will return {@code 0} if {@code str} is not null. This method uses {@link String#indexOf(String)} if + * possible. + *

+ * + *
+     * StringUtils.indexOfAny(null, *)                    = -1
+     * StringUtils.indexOfAny(*, null)                    = -1
+     * StringUtils.indexOfAny(*, [])                      = -1
+     * StringUtils.indexOfAny("zzabyycdxx", "ab", "cd")   = 2
+     * StringUtils.indexOfAny("zzabyycdxx", "cd", "ab")   = 2
+     * StringUtils.indexOfAny("zzabyycdxx", "mn", "op")   = -1
+     * StringUtils.indexOfAny("zzabyycdxx", "zab", "aby") = 1
+     * StringUtils.indexOfAny("zzabyycdxx", "")           = 0
+     * StringUtils.indexOfAny("", "")                     = 0
+     * StringUtils.indexOfAny("", "a")                    = -1
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStrs the CharSequences to search for, may be null. + * @return the first index of any of the searchStrs in str, -1 if no match. + * @since 3.0 Changed signature from indexOfAny(String, String[]) to indexOfAny(CharSequence, CharSequence...) + */ + public static int indexOfAny(final CharSequence str, final CharSequence... searchStrs) { + if (str == null || searchStrs == null) { + return INDEX_NOT_FOUND; + } + // String's can't have a MAX_VALUEth index. + int ret = Integer.MAX_VALUE; + int tmp; + for (final CharSequence search : searchStrs) { + if (search == null) { + continue; + } + tmp = CharSequenceUtils.indexOf(str, search, 0); + if (tmp == INDEX_NOT_FOUND) { + continue; + } + if (tmp < ret) { + ret = tmp; + } + } + return ret == Integer.MAX_VALUE ? INDEX_NOT_FOUND : ret; + } + + /** + * Search a CharSequence to find the first index of any character in the given set of characters. + * + *

+ * A {@code null} String will return {@code -1}. A {@code null} or zero length search array will return {@code -1}. + *

+ *

+ * The following is the same as {@code indexOfAny(cs, 0, searchChars)}. + *

+ *
+     * StringUtils.indexOfAny(null, 0, *)                  = -1
+     * StringUtils.indexOfAny("", 0, *)                    = -1
+     * StringUtils.indexOfAny(*, 0, null)                  = -1
+     * StringUtils.indexOfAny(*, 0, [])                    = -1
+     * StringUtils.indexOfAny("zzabyycdxx", 0, ['z', 'a']) = 0
+     * StringUtils.indexOfAny("zzabyycdxx", 0, ['b', 'y']) = 3
+     * StringUtils.indexOfAny("aba", 0, ['z'])             = -1
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param csStart Start searching the input {@code cs} at this index. + * @param searchChars the chars to search for, may be null. + * @return the index of any of the chars, -1 if no match or null input. + * @since 2.0 + * @since 3.0 Changed signature from indexOfAny(String, char[]) to indexOfAny(CharSequence, char...) + */ + public static int indexOfAny(final CharSequence cs, final int csStart, final char... searchChars) { + if (isEmpty(cs) || ArrayUtils.isEmpty(searchChars)) { + return INDEX_NOT_FOUND; + } + final int csLen = cs.length(); + final int csLast = csLen - 1; + final int searchLen = searchChars.length; + final int searchLast = searchLen - 1; + for (int i = csStart; i < csLen; i++) { + final char ch = cs.charAt(i); + for (int j = 0; j < searchLen; j++) { + if (searchChars[j] == ch) { + // ch is a supplementary character + if (i >= csLast || j >= searchLast || !Character.isHighSurrogate(ch) || searchChars[j + 1] == cs.charAt(i + 1)) { + return i; + } + } + } + } + return INDEX_NOT_FOUND; + } + + /** + * Search a CharSequence to find the first index of any character in the given set of characters. + * + *

+ * A {@code null} String will return {@code -1}. A {@code null} search string will return {@code -1}. + *

+ * + *
+     * StringUtils.indexOfAny(null, *)            = -1
+     * StringUtils.indexOfAny("", *)              = -1
+     * StringUtils.indexOfAny(*, null)            = -1
+     * StringUtils.indexOfAny(*, "")              = -1
+     * StringUtils.indexOfAny("zzabyycdxx", "za") = 0
+     * StringUtils.indexOfAny("zzabyycdxx", "by") = 3
+     * StringUtils.indexOfAny("aba", "z")         = -1
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param searchChars the chars to search for, may be null. + * @return the index of any of the chars, -1 if no match or null input. + * @since 2.0 + * @since 3.0 Changed signature from indexOfAny(String, String) to indexOfAny(CharSequence, String) + */ + public static int indexOfAny(final CharSequence cs, final String searchChars) { + if (isEmpty(cs) || isEmpty(searchChars)) { + return INDEX_NOT_FOUND; + } + return indexOfAny(cs, searchChars.toCharArray()); + } + + /** + * Searches a CharSequence to find the first index of any character not in the given set of characters, i.e., find index i of first char in cs such that + * (cs.codePointAt(i) ∉ { x ∈ codepoints(searchChars) }) + * + *

+ * A {@code null} CharSequence will return {@code -1}. A {@code null} or zero length search array will return {@code -1}. + *

+ * + *
+     * StringUtils.indexOfAnyBut(null, *)                              = -1
+     * StringUtils.indexOfAnyBut("", *)                                = -1
+     * StringUtils.indexOfAnyBut(*, null)                              = -1
+     * StringUtils.indexOfAnyBut(*, [])                                = -1
+     * StringUtils.indexOfAnyBut("zzabyycdxx", new char[] {'z', 'a'} ) = 3
+     * StringUtils.indexOfAnyBut("aba", new char[] {'z'} )             = 0
+     * StringUtils.indexOfAnyBut("aba", new char[] {'a', 'b'} )        = -1
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @param searchChars the chars to search for, may be null. + * @return the index of any of the chars, -1 if no match or null input. + * @since 2.0 + * @since 3.0 Changed signature from indexOfAnyBut(String, char[]) to indexOfAnyBut(CharSequence, char...) + */ + public static int indexOfAnyBut(final CharSequence cs, final char... searchChars) { + if (isEmpty(cs) || ArrayUtils.isEmpty(searchChars)) { + return INDEX_NOT_FOUND; + } + return indexOfAnyBut(cs, CharBuffer.wrap(searchChars)); + } + + /** + * Search a CharSequence to find the first index of any character not in the given set of characters, i.e., find index i of first char in seq such that + * (seq.codePointAt(i) ∉ { x ∈ codepoints(searchChars) }) + * + *

+ * A {@code null} CharSequence will return {@code -1}. A {@code null} or empty search string will return {@code -1}. + *

+ * + *
+     * StringUtils.indexOfAnyBut(null, *)            = -1
+     * StringUtils.indexOfAnyBut("", *)              = -1
+     * StringUtils.indexOfAnyBut(*, null)            = -1
+     * StringUtils.indexOfAnyBut(*, "")              = -1
+     * StringUtils.indexOfAnyBut("zzabyycdxx", "za") = 3
+     * StringUtils.indexOfAnyBut("zzabyycdxx", "")   = -1
+     * StringUtils.indexOfAnyBut("aba", "ab")        = -1
+     * 
+ * + * @param seq the CharSequence to check, may be null. + * @param searchChars the chars to search for, may be null. + * @return the index of any of the chars, -1 if no match or null input. + * @since 2.0 + * @since 3.0 Changed signature from indexOfAnyBut(String, String) to indexOfAnyBut(CharSequence, CharSequence) + */ + public static int indexOfAnyBut(final CharSequence seq, final CharSequence searchChars) { + if (isEmpty(seq) || isEmpty(searchChars)) { + return INDEX_NOT_FOUND; + } + final Set searchSetCodePoints = searchChars.codePoints() + .boxed().collect(Collectors.toSet()); + // advance character index from one interpreted codepoint to the next + for (int curSeqCharIdx = 0; curSeqCharIdx < seq.length();) { + final int curSeqCodePoint = Character.codePointAt(seq, curSeqCharIdx); + if (!searchSetCodePoints.contains(curSeqCodePoint)) { + return curSeqCharIdx; + } + curSeqCharIdx += Character.charCount(curSeqCodePoint); // skip indices to paired low-surrogates + } + return INDEX_NOT_FOUND; + } + + /** + * Compares all CharSequences in an array and returns the index at which the CharSequences begin to differ. + * + *

+ * For example, {@code indexOfDifference(new String[] {"i am a machine", "i am a robot"}) -> 7} + *

+ * + *
+     * StringUtils.indexOfDifference(null)                             = -1
+     * StringUtils.indexOfDifference(new String[] {})                  = -1
+     * StringUtils.indexOfDifference(new String[] {"abc"})             = -1
+     * StringUtils.indexOfDifference(new String[] {null, null})        = -1
+     * StringUtils.indexOfDifference(new String[] {"", ""})            = -1
+     * StringUtils.indexOfDifference(new String[] {"", null})          = 0
+     * StringUtils.indexOfDifference(new String[] {"abc", null, null}) = 0
+     * StringUtils.indexOfDifference(new String[] {null, null, "abc"}) = 0
+     * StringUtils.indexOfDifference(new String[] {"", "abc"})         = 0
+     * StringUtils.indexOfDifference(new String[] {"abc", ""})         = 0
+     * StringUtils.indexOfDifference(new String[] {"abc", "abc"})      = -1
+     * StringUtils.indexOfDifference(new String[] {"abc", "a"})        = 1
+     * StringUtils.indexOfDifference(new String[] {"ab", "abxyz"})     = 2
+     * StringUtils.indexOfDifference(new String[] {"abcde", "abxyz"})  = 2
+     * StringUtils.indexOfDifference(new String[] {"abcde", "xyz"})    = 0
+     * StringUtils.indexOfDifference(new String[] {"xyz", "abcde"})    = 0
+     * StringUtils.indexOfDifference(new String[] {"i am a machine", "i am a robot"}) = 7
+     * 
+ * + * @param css array of CharSequences, entries may be null. + * @return the index where the strings begin to differ; -1 if they are all equal. + * @since 2.4 + * @since 3.0 Changed signature from indexOfDifference(String...) to indexOfDifference(CharSequence...) + */ + public static int indexOfDifference(final CharSequence... css) { + if (ArrayUtils.getLength(css) <= 1) { + return INDEX_NOT_FOUND; + } + boolean anyStringNull = false; + boolean allStringsNull = true; + final int arrayLen = css.length; + int shortestStrLen = Integer.MAX_VALUE; + int longestStrLen = 0; + // find the min and max string lengths; this avoids checking to make + // sure we are not exceeding the length of the string each time through + // the bottom loop. + for (final CharSequence cs : css) { + if (cs == null) { + anyStringNull = true; + shortestStrLen = 0; + } else { + allStringsNull = false; + shortestStrLen = Math.min(cs.length(), shortestStrLen); + longestStrLen = Math.max(cs.length(), longestStrLen); + } + } + // handle lists containing all nulls or all empty strings + if (allStringsNull || longestStrLen == 0 && !anyStringNull) { + return INDEX_NOT_FOUND; + } + // handle lists containing some nulls or some empty strings + if (shortestStrLen == 0) { + return 0; + } + // find the position with the first difference across all strings + int firstDiff = -1; + for (int stringPos = 0; stringPos < shortestStrLen; stringPos++) { + final char comparisonChar = css[0].charAt(stringPos); + for (int arrayPos = 1; arrayPos < arrayLen; arrayPos++) { + if (css[arrayPos].charAt(stringPos) != comparisonChar) { + firstDiff = stringPos; + break; + } + } + if (firstDiff != -1) { + break; + } + } + if (firstDiff == -1 && shortestStrLen != longestStrLen) { + // we compared all of the characters up to the length of the + // shortest string and didn't find a match, but the string lengths + // vary, so return the length of the shortest string. + return shortestStrLen; + } + return firstDiff; + } + + /** + * Compares two CharSequences, and returns the index at which the CharSequences begin to differ. + * + *

+ * For example, {@code indexOfDifference("i am a machine", "i am a robot") -> 7} + *

+ * + *
+     * StringUtils.indexOfDifference(null, null)       = -1
+     * StringUtils.indexOfDifference("", "")           = -1
+     * StringUtils.indexOfDifference("", "abc")        = 0
+     * StringUtils.indexOfDifference("abc", "")        = 0
+     * StringUtils.indexOfDifference("abc", "abc")     = -1
+     * StringUtils.indexOfDifference("ab", "abxyz")    = 2
+     * StringUtils.indexOfDifference("abcde", "abxyz") = 2
+     * StringUtils.indexOfDifference("abcde", "xyz")   = 0
+     * 
+ * + * @param cs1 the first CharSequence, may be null. + * @param cs2 the second CharSequence, may be null. + * @return the index where cs1 and cs2 begin to differ; -1 if they are equal. + * @since 2.0 + * @since 3.0 Changed signature from indexOfDifference(String, String) to indexOfDifference(CharSequence, CharSequence) + */ + public static int indexOfDifference(final CharSequence cs1, final CharSequence cs2) { + if (cs1 == cs2) { + return INDEX_NOT_FOUND; + } + if (cs1 == null || cs2 == null) { + return 0; + } + int i; + for (i = 0; i < cs1.length() && i < cs2.length(); ++i) { + if (cs1.charAt(i) != cs2.charAt(i)) { + break; + } + } + if (i < cs2.length() || i < cs1.length()) { + return i; + } + return INDEX_NOT_FOUND; + } + + /** + * Case in-sensitive find of the first index within a CharSequence. + * + *

+ * A {@code null} CharSequence will return {@code -1}. A negative start position is treated as zero. An empty ("") search CharSequence always matches. A + * start position greater than the string length only matches an empty search CharSequence. + *

+ * + *
+     * StringUtils.indexOfIgnoreCase(null, *)          = -1
+     * StringUtils.indexOfIgnoreCase(*, null)          = -1
+     * StringUtils.indexOfIgnoreCase("", "")           = 0
+     * StringUtils.indexOfIgnoreCase(" ", " ")         = 0
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "a")  = 0
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "b")  = 2
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "ab") = 1
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStr the CharSequence to find, may be null. + * @return the first index of the search CharSequence, -1 if no match or {@code null} string input. + * @since 2.5 + * @since 3.0 Changed signature from indexOfIgnoreCase(String, String) to indexOfIgnoreCase(CharSequence, CharSequence) + * @deprecated Use {@link Strings#indexOf(CharSequence, CharSequence) Strings.CI.indexOf(CharSequence, CharSequence)}. + */ + @Deprecated + public static int indexOfIgnoreCase(final CharSequence str, final CharSequence searchStr) { + return Strings.CI.indexOf(str, searchStr); + } + + /** + * Case in-sensitive find of the first index within a CharSequence from the specified position. + * + *

+ * A {@code null} CharSequence will return {@code -1}. A negative start position is treated as zero. An empty ("") search CharSequence always matches. A + * start position greater than the string length only matches an empty search CharSequence. + *

+ * + *
+     * StringUtils.indexOfIgnoreCase(null, *, *)          = -1
+     * StringUtils.indexOfIgnoreCase(*, null, *)          = -1
+     * StringUtils.indexOfIgnoreCase("", "", 0)           = 0
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "A", 0)  = 0
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "B", 0)  = 2
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "AB", 0) = 1
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "B", 3)  = 5
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "B", 9)  = -1
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "B", -1) = 2
+     * StringUtils.indexOfIgnoreCase("aabaabaa", "", 2)   = 2
+     * StringUtils.indexOfIgnoreCase("abc", "", 9)        = -1
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStr the CharSequence to find, may be null. + * @param startPos the start position, negative treated as zero. + * @return the first index of the search CharSequence (always ≥ startPos), -1 if no match or {@code null} string input. + * @since 2.5 + * @since 3.0 Changed signature from indexOfIgnoreCase(String, String, int) to indexOfIgnoreCase(CharSequence, CharSequence, int) + * @deprecated Use {@link Strings#indexOf(CharSequence, CharSequence, int) Strings.CI.indexOf(CharSequence, CharSequence, int)}. + */ + @Deprecated + public static int indexOfIgnoreCase(final CharSequence str, final CharSequence searchStr, final int startPos) { + return Strings.CI.indexOf(str, searchStr, startPos); + } + + /** + * Tests if all of the CharSequences are empty (""), null or whitespace only. + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.isAllBlank(null)             = true
+     * StringUtils.isAllBlank(null, "foo")      = false
+     * StringUtils.isAllBlank(null, null)       = true
+     * StringUtils.isAllBlank("", "bar")        = false
+     * StringUtils.isAllBlank("bob", "")        = false
+     * StringUtils.isAllBlank("  bob  ", null)  = false
+     * StringUtils.isAllBlank(" ", "bar")       = false
+     * StringUtils.isAllBlank("foo", "bar")     = false
+     * StringUtils.isAllBlank(new String[] {})  = true
+     * 
+ * + * @param css the CharSequences to check, may be null or empty. + * @return {@code true} if all of the CharSequences are empty or null or whitespace only. + * @since 3.6 + */ + public static boolean isAllBlank(final CharSequence... css) { + if (ArrayUtils.isEmpty(css)) { + return true; + } + for (final CharSequence cs : css) { + if (isNotBlank(cs)) { + return false; + } + } + return true; + } + + /** + * Tests if all of the CharSequences are empty ("") or null. + * + *
+     * StringUtils.isAllEmpty(null)             = true
+     * StringUtils.isAllEmpty(null, "")         = true
+     * StringUtils.isAllEmpty(new String[] {})  = true
+     * StringUtils.isAllEmpty(null, "foo")      = false
+     * StringUtils.isAllEmpty("", "bar")        = false
+     * StringUtils.isAllEmpty("bob", "")        = false
+     * StringUtils.isAllEmpty("  bob  ", null)  = false
+     * StringUtils.isAllEmpty(" ", "bar")       = false
+     * StringUtils.isAllEmpty("foo", "bar")     = false
+     * 
+ * + * @param css the CharSequences to check, may be null or empty. + * @return {@code true} if all of the CharSequences are empty or null. + * @since 3.6 + */ + public static boolean isAllEmpty(final CharSequence... css) { + if (ArrayUtils.isEmpty(css)) { + return true; + } + for (final CharSequence cs : css) { + if (isNotEmpty(cs)) { + return false; + } + } + return true; + } + + /** + * Tests if the CharSequence contains only lowercase characters. + * + *

+ * {@code null} will return {@code false}. An empty CharSequence (length()=0) will return {@code false}. + *

+ * + *
+     * StringUtils.isAllLowerCase(null)   = false
+     * StringUtils.isAllLowerCase("")     = false
+     * StringUtils.isAllLowerCase("  ")   = false
+     * StringUtils.isAllLowerCase("abc")  = true
+     * StringUtils.isAllLowerCase("abC")  = false
+     * StringUtils.isAllLowerCase("ab c") = false
+     * StringUtils.isAllLowerCase("ab1c") = false
+     * StringUtils.isAllLowerCase("ab/c") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains lowercase characters, and is non-null. + * @since 2.5 + * @since 3.0 Changed signature from isAllLowerCase(String) to isAllLowerCase(CharSequence) + */ + public static boolean isAllLowerCase(final CharSequence cs) { + if (isEmpty(cs)) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + if (!Character.isLowerCase(cs.charAt(i))) { + return false; + } + } + return true; + } + + /** + * Tests if the CharSequence contains only uppercase characters. + * + *

{@code null} will return {@code false}. + * An empty String (length()=0) will return {@code false}.

+ * + *
+     * StringUtils.isAllUpperCase(null)   = false
+     * StringUtils.isAllUpperCase("")     = false
+     * StringUtils.isAllUpperCase("  ")   = false
+     * StringUtils.isAllUpperCase("ABC")  = true
+     * StringUtils.isAllUpperCase("aBC")  = false
+     * StringUtils.isAllUpperCase("A C")  = false
+     * StringUtils.isAllUpperCase("A1C")  = false
+     * StringUtils.isAllUpperCase("A/C")  = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains uppercase characters, and is non-null. + * @since 2.5 + * @since 3.0 Changed signature from isAllUpperCase(String) to isAllUpperCase(CharSequence) + */ + public static boolean isAllUpperCase(final CharSequence cs) { + if (isEmpty(cs)) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + if (!Character.isUpperCase(cs.charAt(i))) { + return false; + } + } + return true; + } + + /** + * Tests if the CharSequence contains only Unicode letters. + * + *

+ * {@code null} will return {@code false}. An empty CharSequence (length()=0) will return {@code false}. + *

+ * + *
+     * StringUtils.isAlpha(null)   = false
+     * StringUtils.isAlpha("")     = false
+     * StringUtils.isAlpha("  ")   = false
+     * StringUtils.isAlpha("abc")  = true
+     * StringUtils.isAlpha("ab2c") = false
+     * StringUtils.isAlpha("ab-c") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains letters, and is non-null. + * @since 3.0 Changed signature from isAlpha(String) to isAlpha(CharSequence) + * @since 3.0 Changed "" to return false and not true + */ + public static boolean isAlpha(final CharSequence cs) { + if (isEmpty(cs)) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + if (!Character.isLetter(cs.charAt(i))) { + return false; + } + } + return true; + } + + /** + * Tests if the CharSequence contains only Unicode letters or digits. + * + *

+ * {@code null} will return {@code false}. An empty CharSequence (length()=0) will return {@code false}. + *

+ * + *
+     * StringUtils.isAlphanumeric(null)   = false
+     * StringUtils.isAlphanumeric("")     = false
+     * StringUtils.isAlphanumeric("  ")   = false
+     * StringUtils.isAlphanumeric("abc")  = true
+     * StringUtils.isAlphanumeric("ab c") = false
+     * StringUtils.isAlphanumeric("ab2c") = true
+     * StringUtils.isAlphanumeric("ab-c") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains letters or digits, and is non-null. + * @since 3.0 Changed signature from isAlphanumeric(String) to isAlphanumeric(CharSequence) + * @since 3.0 Changed "" to return false and not true + */ + public static boolean isAlphanumeric(final CharSequence cs) { + if (isEmpty(cs)) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + if (!Character.isLetterOrDigit(cs.charAt(i))) { + return false; + } + } + return true; + } + + /** + * Tests if the CharSequence contains only Unicode letters, digits or space ({@code ' '}). + * + *

+ * {@code null} will return {@code false}. An empty CharSequence (length()=0) will return {@code true}. + *

+ * + *
+     * StringUtils.isAlphanumericSpace(null)   = false
+     * StringUtils.isAlphanumericSpace("")     = true
+     * StringUtils.isAlphanumericSpace("  ")   = true
+     * StringUtils.isAlphanumericSpace("abc")  = true
+     * StringUtils.isAlphanumericSpace("ab c") = true
+     * StringUtils.isAlphanumericSpace("ab2c") = true
+     * StringUtils.isAlphanumericSpace("ab-c") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains letters, digits or space, and is non-null. + * @since 3.0 Changed signature from isAlphanumericSpace(String) to isAlphanumericSpace(CharSequence) + */ + public static boolean isAlphanumericSpace(final CharSequence cs) { + if (cs == null) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + final char nowChar = cs.charAt(i); + if (nowChar != ' ' && !Character.isLetterOrDigit(nowChar)) { + return false; + } + } + return true; + } + + /** + * Tests if the CharSequence contains only Unicode letters and space (' '). + * + *

+ * {@code null} will return {@code false} An empty CharSequence (length()=0) will return {@code true}. + *

+ * + *
+     * StringUtils.isAlphaSpace(null)   = false
+     * StringUtils.isAlphaSpace("")     = true
+     * StringUtils.isAlphaSpace("  ")   = true
+     * StringUtils.isAlphaSpace("abc")  = true
+     * StringUtils.isAlphaSpace("ab c") = true
+     * StringUtils.isAlphaSpace("ab2c") = false
+     * StringUtils.isAlphaSpace("ab-c") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains letters and space, and is non-null. + * @since 3.0 Changed signature from isAlphaSpace(String) to isAlphaSpace(CharSequence) + */ + public static boolean isAlphaSpace(final CharSequence cs) { + if (cs == null) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + final char nowChar = cs.charAt(i); + if (nowChar != ' ' && !Character.isLetter(nowChar)) { + return false; + } + } + return true; + } + + /** + * Tests if any of the CharSequences are {@link #isBlank(CharSequence) blank} (whitespaces, empty ({@code ""}), or {@code null}). + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.isAnyBlank((String) null)    = true
+     * StringUtils.isAnyBlank((String[]) null)  = false
+     * StringUtils.isAnyBlank(null, "foo")      = true
+     * StringUtils.isAnyBlank(null, null)       = true
+     * StringUtils.isAnyBlank("", "bar")        = true
+     * StringUtils.isAnyBlank("bob", "")        = true
+     * StringUtils.isAnyBlank("  bob  ", null)  = true
+     * StringUtils.isAnyBlank(" ", "bar")       = true
+     * StringUtils.isAnyBlank(new String[] {})  = false
+     * StringUtils.isAnyBlank(new String[]{""}) = true
+     * StringUtils.isAnyBlank("foo", "bar")     = false
+     * 
+ * + * @param css the CharSequences to check, may be null or empty. + * @return {@code true} if any of the CharSequences are {@link #isBlank(CharSequence) blank} (whitespaces, empty ({@code ""}), or {@code null}). + * @see #isBlank(CharSequence) + * @since 3.2 + */ + public static boolean isAnyBlank(final CharSequence... css) { + if (ArrayUtils.isEmpty(css)) { + return false; + } + for (final CharSequence cs : css) { + if (isBlank(cs)) { + return true; + } + } + return false; + } + + /** + * Tests if any of the CharSequences are empty ("") or null. + * + *
+     * StringUtils.isAnyEmpty((String) null)    = true
+     * StringUtils.isAnyEmpty((String[]) null)  = false
+     * StringUtils.isAnyEmpty(null, "foo")      = true
+     * StringUtils.isAnyEmpty("", "bar")        = true
+     * StringUtils.isAnyEmpty("bob", "")        = true
+     * StringUtils.isAnyEmpty("  bob  ", null)  = true
+     * StringUtils.isAnyEmpty(" ", "bar")       = false
+     * StringUtils.isAnyEmpty("foo", "bar")     = false
+     * StringUtils.isAnyEmpty(new String[]{})   = false
+     * StringUtils.isAnyEmpty(new String[]{""}) = true
+     * 
+ * + * @param css the CharSequences to check, may be null or empty. + * @return {@code true} if any of the CharSequences are empty or null. + * @since 3.2 + */ + public static boolean isAnyEmpty(final CharSequence... css) { + if (ArrayUtils.isEmpty(css)) { + return false; + } + for (final CharSequence cs : css) { + if (isEmpty(cs)) { + return true; + } + } + return false; + } + + /** + * Tests if the CharSequence contains only ASCII printable characters. + * + *

+ * {@code null} will return {@code false}. An empty CharSequence (length()=0) will return {@code true}. + *

+ * + *
+     * StringUtils.isAsciiPrintable(null)     = false
+     * StringUtils.isAsciiPrintable("")       = true
+     * StringUtils.isAsciiPrintable(" ")      = true
+     * StringUtils.isAsciiPrintable("Ceki")   = true
+     * StringUtils.isAsciiPrintable("ab2c")   = true
+     * StringUtils.isAsciiPrintable("!ab-c~") = true
+     * StringUtils.isAsciiPrintable("\u0020") = true
+     * StringUtils.isAsciiPrintable("\u0021") = true
+     * StringUtils.isAsciiPrintable("\u007e") = true
+     * StringUtils.isAsciiPrintable("\u007f") = false
+     * StringUtils.isAsciiPrintable("Ceki G\u00fclc\u00fc") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if every character is in the range 32 through 126. + * @since 2.1 + * @since 3.0 Changed signature from isAsciiPrintable(String) to isAsciiPrintable(CharSequence) + */ + public static boolean isAsciiPrintable(final CharSequence cs) { + if (cs == null) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + if (!CharUtils.isAsciiPrintable(cs.charAt(i))) { + return false; + } + } + return true; + } + + /** + * Tests if a CharSequence is empty ({@code "")}, null, or contains only whitespace as defined by {@link Character#isWhitespace(char)}. + * + *
+     * StringUtils.isBlank(null)      = true
+     * StringUtils.isBlank("")        = true
+     * StringUtils.isBlank(" ")       = true
+     * StringUtils.isBlank("bob")     = false
+     * StringUtils.isBlank("  bob  ") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if the CharSequence is null, empty or whitespace only. + * @since 2.0 + * @since 3.0 Changed signature from isBlank(String) to isBlank(CharSequence) + */ + public static boolean isBlank(final CharSequence cs) { + final int strLen = length(cs); + for (int i = 0; i < strLen; i++) { + if (!Character.isWhitespace(cs.charAt(i))) { + return false; + } + } + return true; + } + + /** + * Tests if a CharSequence is empty ("") or null. + * + *
+     * StringUtils.isEmpty(null)      = true
+     * StringUtils.isEmpty("")        = true
+     * StringUtils.isEmpty(" ")       = false
+     * StringUtils.isEmpty("bob")     = false
+     * StringUtils.isEmpty("  bob  ") = false
+     * 
+ * + *

+ * NOTE: This method changed in Lang version 2.0. It no longer trims the CharSequence. That functionality is available in isBlank(). + *

+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if the CharSequence is empty or null. + * @since 3.0 Changed signature from isEmpty(String) to isEmpty(CharSequence) + */ + public static boolean isEmpty(final CharSequence cs) { + return cs == null || cs.length() == 0; + } + + /** + * Tests if the CharSequence contains mixed casing of both uppercase and lowercase characters. + * + *

+ * {@code null} will return {@code false}. An empty CharSequence ({@code length()=0}) will return {@code false}. + *

+ * + *
+     * StringUtils.isMixedCase(null)    = false
+     * StringUtils.isMixedCase("")      = false
+     * StringUtils.isMixedCase(" ")     = false
+     * StringUtils.isMixedCase("ABC")   = false
+     * StringUtils.isMixedCase("abc")   = false
+     * StringUtils.isMixedCase("aBc")   = true
+     * StringUtils.isMixedCase("A c")   = true
+     * StringUtils.isMixedCase("A1c")   = true
+     * StringUtils.isMixedCase("a/C")   = true
+     * StringUtils.isMixedCase("aC\t")  = true
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if the CharSequence contains both uppercase and lowercase characters. + * @since 3.5 + */ + public static boolean isMixedCase(final CharSequence cs) { + if (isEmpty(cs) || cs.length() == 1) { + return false; + } + boolean containsUppercase = false; + boolean containsLowercase = false; + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + final char nowChar = cs.charAt(i); + if (Character.isUpperCase(nowChar)) { + containsUppercase = true; + } else if (Character.isLowerCase(nowChar)) { + containsLowercase = true; + } + if (containsUppercase && containsLowercase) { + return true; + } + } + return false; + } + + /** + * Tests if none of the CharSequences are empty (""), null or whitespace only. + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.isNoneBlank((String) null)    = false
+     * StringUtils.isNoneBlank((String[]) null)  = true
+     * StringUtils.isNoneBlank(null, "foo")      = false
+     * StringUtils.isNoneBlank(null, null)       = false
+     * StringUtils.isNoneBlank("", "bar")        = false
+     * StringUtils.isNoneBlank("bob", "")        = false
+     * StringUtils.isNoneBlank("  bob  ", null)  = false
+     * StringUtils.isNoneBlank(" ", "bar")       = false
+     * StringUtils.isNoneBlank(new String[] {})  = true
+     * StringUtils.isNoneBlank(new String[]{""}) = false
+     * StringUtils.isNoneBlank("foo", "bar")     = true
+     * 
+ * + * @param css the CharSequences to check, may be null or empty. + * @return {@code true} if none of the CharSequences are empty or null or whitespace only. + * @since 3.2 + */ + public static boolean isNoneBlank(final CharSequence... css) { + return !isAnyBlank(css); + } + + /** + * Tests if none of the CharSequences are empty ("") or null. + * + *
+     * StringUtils.isNoneEmpty((String) null)    = false
+     * StringUtils.isNoneEmpty((String[]) null)  = true
+     * StringUtils.isNoneEmpty(null, "foo")      = false
+     * StringUtils.isNoneEmpty("", "bar")        = false
+     * StringUtils.isNoneEmpty("bob", "")        = false
+     * StringUtils.isNoneEmpty("  bob  ", null)  = false
+     * StringUtils.isNoneEmpty(new String[] {})  = true
+     * StringUtils.isNoneEmpty(new String[]{""}) = false
+     * StringUtils.isNoneEmpty(" ", "bar")       = true
+     * StringUtils.isNoneEmpty("foo", "bar")     = true
+     * 
+ * + * @param css the CharSequences to check, may be null or empty. + * @return {@code true} if none of the CharSequences are empty or null. + * @since 3.2 + */ + public static boolean isNoneEmpty(final CharSequence... css) { + return !isAnyEmpty(css); + } + + /** + * Tests if a CharSequence is not {@link #isBlank(CharSequence) blank} (whitespaces, empty ({@code ""}), or {@code null}). + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.isNotBlank(null)      = false
+     * StringUtils.isNotBlank("")        = false
+     * StringUtils.isNotBlank(" ")       = false
+     * StringUtils.isNotBlank("bob")     = true
+     * StringUtils.isNotBlank("  bob  ") = true
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if the CharSequence is not {@link #isBlank(CharSequence) blank} (whitespaces, empty ({@code ""}), or {@code null}). + * @see #isBlank(CharSequence) + * @since 2.0 + * @since 3.0 Changed signature from isNotBlank(String) to isNotBlank(CharSequence) + */ + public static boolean isNotBlank(final CharSequence cs) { + return !isBlank(cs); + } + + /** + * Tests if a CharSequence is not empty ("") and not null. + * + *
+     * StringUtils.isNotEmpty(null)      = false
+     * StringUtils.isNotEmpty("")        = false
+     * StringUtils.isNotEmpty(" ")       = true
+     * StringUtils.isNotEmpty("bob")     = true
+     * StringUtils.isNotEmpty("  bob  ") = true
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if the CharSequence is not empty and not null. + * @since 3.0 Changed signature from isNotEmpty(String) to isNotEmpty(CharSequence) + */ + public static boolean isNotEmpty(final CharSequence cs) { + return !isEmpty(cs); + } + + /** + * Tests if the CharSequence contains only Unicode digits. A decimal point is not a Unicode digit and returns false. + * + *

+ * {@code null} will return {@code false}. An empty CharSequence (length()=0) will return {@code false}. + *

+ * + *

+ * Note that the method does not allow for a leading sign, either positive or negative. Also, if a String passes the numeric test, it may still generate a + * NumberFormatException when parsed by Integer.parseInt or Long.parseLong, e.g. if the value is outside the range for int or long respectively. + *

+ * + *
+     * StringUtils.isNumeric(null)   = false
+     * StringUtils.isNumeric("")     = false
+     * StringUtils.isNumeric("  ")   = false
+     * StringUtils.isNumeric("123")  = true
+     * StringUtils.isNumeric("\u0967\u0968\u0969")  = true
+     * StringUtils.isNumeric("12 3") = false
+     * StringUtils.isNumeric("ab2c") = false
+     * StringUtils.isNumeric("12-3") = false
+     * StringUtils.isNumeric("12.3") = false
+     * StringUtils.isNumeric("-123") = false
+     * StringUtils.isNumeric("+123") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains digits, and is non-null. + * @since 3.0 Changed signature from isNumeric(String) to isNumeric(CharSequence) + * @since 3.0 Changed "" to return false and not true + */ + public static boolean isNumeric(final CharSequence cs) { + if (isEmpty(cs)) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + if (!Character.isDigit(cs.charAt(i))) { + return false; + } + } + return true; + } + + /** + * Tests if the CharSequence contains only Unicode digits or space ({@code ' '}). A decimal point is not a Unicode digit and returns false. + * + *

+ * {@code null} will return {@code false}. An empty CharSequence (length()=0) will return {@code true}. + *

+ * + *
+     * StringUtils.isNumericSpace(null)   = false
+     * StringUtils.isNumericSpace("")     = true
+     * StringUtils.isNumericSpace("  ")   = true
+     * StringUtils.isNumericSpace("123")  = true
+     * StringUtils.isNumericSpace("12 3") = true
+     * StringUtils.isNumericSpace("\u0967\u0968\u0969")   = true
+     * StringUtils.isNumericSpace("\u0967\u0968 \u0969")  = true
+     * StringUtils.isNumericSpace("ab2c") = false
+     * StringUtils.isNumericSpace("12-3") = false
+     * StringUtils.isNumericSpace("12.3") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains digits or space, and is non-null. + * @since 3.0 Changed signature from isNumericSpace(String) to isNumericSpace(CharSequence) + */ + public static boolean isNumericSpace(final CharSequence cs) { + if (cs == null) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + final char nowChar = cs.charAt(i); + if (nowChar != ' ' && !Character.isDigit(nowChar)) { + return false; + } + } + return true; + } + + /** + * Tests if the CharSequence contains only whitespace. + * + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *

+ * {@code null} will return {@code false}. An empty CharSequence (length()=0) will return {@code true}. + *

+ * + *
+     * StringUtils.isWhitespace(null)   = false
+     * StringUtils.isWhitespace("")     = true
+     * StringUtils.isWhitespace("  ")   = true
+     * StringUtils.isWhitespace("abc")  = false
+     * StringUtils.isWhitespace("ab2c") = false
+     * StringUtils.isWhitespace("ab-c") = false
+     * 
+ * + * @param cs the CharSequence to check, may be null. + * @return {@code true} if only contains whitespace, and is non-null. + * @since 2.0 + * @since 3.0 Changed signature from isWhitespace(String) to isWhitespace(CharSequence) + */ + public static boolean isWhitespace(final CharSequence cs) { + if (cs == null) { + return false; + } + final int sz = cs.length(); + for (int i = 0; i < sz; i++) { + if (!Character.isWhitespace(cs.charAt(i))) { + return false; + } + } + return true; + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)             = null
+     * StringUtils.join([], *)               = ""
+     * StringUtils.join([null], *)           = ""
+     * StringUtils.join([false, false], ';') = "false;false"
+     * 
+ * + * @param array the array of values to join together, may be null. + * @param delimiter the separator character to use. + * @return the joined String, {@code null} if null array input. + * @since 3.12.0 + */ + public static String join(final boolean[] array, final char delimiter) { + if (array == null) { + return null; + } + return join(array, delimiter, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)                  = null
+     * StringUtils.join([], *)                    = ""
+     * StringUtils.join([null], *)                = ""
+     * StringUtils.join([true, false, true], ';') = "true;false;true"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @param startIndex + * the first index to start joining from. It is an error to pass in a start index past the end of the + * array. + * @param endIndex + * the index to stop joining from (exclusive). It is an error to pass in an end index past the end of + * the array. + * @return the joined String, {@code null} if null array input. + * @since 3.12.0 + */ + public static String join(final boolean[] array, final char delimiter, final int startIndex, final int endIndex) { + // See StringUtilsJoinBenchmark + if (array == null) { + return null; + } + final int count = endIndex - startIndex; + if (count <= 0) { + return EMPTY; + } + final byte maxElementChars = 5; // "false" + final StringBuilder stringBuilder = capacity(count, maxElementChars); + stringBuilder.append(array[startIndex]); + for (int i = startIndex + 1; i < endIndex; i++) { + stringBuilder.append(delimiter).append(array[i]); + } + return stringBuilder.toString(); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)         = null
+     * StringUtils.join([], *)           = ""
+     * StringUtils.join([null], *)       = ""
+     * StringUtils.join([1, 2, 3], ';')  = "1;2;3"
+     * StringUtils.join([1, 2, 3], null) = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final byte[] array, final char delimiter) { + if (array == null) { + return null; + } + return join(array, delimiter, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)         = null
+     * StringUtils.join([], *)           = ""
+     * StringUtils.join([null], *)       = ""
+     * StringUtils.join([1, 2, 3], ';')  = "1;2;3"
+     * StringUtils.join([1, 2, 3], null) = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @param startIndex + * the first index to start joining from. It is an error to pass in a start index past the end of the + * array. + * @param endIndex + * the index to stop joining from (exclusive). It is an error to pass in an end index past the end of + * the array. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final byte[] array, final char delimiter, final int startIndex, final int endIndex) { + // See StringUtilsJoinBenchmark + if (array == null) { + return null; + } + final int count = endIndex - startIndex; + if (count <= 0) { + return EMPTY; + } + final byte maxElementChars = 4; // "-128" + final StringBuilder stringBuilder = capacity(count, maxElementChars); + stringBuilder.append(array[startIndex]); + for (int i = startIndex + 1; i < endIndex; i++) { + stringBuilder.append(delimiter).append(array[i]); + } + return stringBuilder.toString(); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)         = null
+     * StringUtils.join([], *)           = ""
+     * StringUtils.join([null], *)       = ""
+     * StringUtils.join([1, 2, 3], ';')  = "1;2;3"
+     * StringUtils.join([1, 2, 3], null) = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final char[] array, final char delimiter) { + if (array == null) { + return null; + } + return join(array, delimiter, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)         = null
+     * StringUtils.join([], *)           = ""
+     * StringUtils.join([null], *)       = ""
+     * StringUtils.join([1, 2, 3], ';')  = "1;2;3"
+     * StringUtils.join([1, 2, 3], null) = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @param startIndex + * the first index to start joining from. It is an error to pass in a start index past the end of the + * array. + * @param endIndex + * the index to stop joining from (exclusive). It is an error to pass in an end index past the end of + * the array. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final char[] array, final char delimiter, final int startIndex, final int endIndex) { + // See StringUtilsJoinBenchmark + if (array == null) { + return null; + } + final int count = endIndex - startIndex; + if (count <= 0) { + return EMPTY; + } + final byte maxElementChars = 1; + final StringBuilder stringBuilder = capacity(count, maxElementChars); + stringBuilder.append(array[startIndex]); + for (int i = startIndex + 1; i < endIndex; i++) { + stringBuilder.append(delimiter).append(array[i]); + } + return stringBuilder.toString(); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)          = null
+     * StringUtils.join([], *)            = ""
+     * StringUtils.join([null], *)        = ""
+     * StringUtils.join([1, 2, 3], ';')   = "1;2;3"
+     * StringUtils.join([1, 2, 3], null)  = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final double[] array, final char delimiter) { + if (array == null) { + return null; + } + return join(array, delimiter, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)          = null
+     * StringUtils.join([], *)            = ""
+     * StringUtils.join([null], *)        = ""
+     * StringUtils.join([1, 2, 3], ';')   = "1;2;3"
+     * StringUtils.join([1, 2, 3], null)  = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @param startIndex + * the first index to start joining from. It is an error to pass in a start index past the end of the + * array. + * @param endIndex + * the index to stop joining from (exclusive). It is an error to pass in an end index past the end of + * the array. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final double[] array, final char delimiter, final int startIndex, final int endIndex) { + // See StringUtilsJoinBenchmark + if (array == null) { + return null; + } + final int count = endIndex - startIndex; + if (count <= 0) { + return EMPTY; + } + final byte maxElementChars = 22; // "1.7976931348623157E308" + final StringBuilder stringBuilder = capacity(count, maxElementChars); + stringBuilder.append(array[startIndex]); + for (int i = startIndex + 1; i < endIndex; i++) { + stringBuilder.append(delimiter).append(array[i]); + } + return stringBuilder.toString(); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)          = null
+     * StringUtils.join([], *)            = ""
+     * StringUtils.join([null], *)        = ""
+     * StringUtils.join([1, 2, 3], ';')   = "1;2;3"
+     * StringUtils.join([1, 2, 3], null)  = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @return the joined String, {@code null} if null array input + * @since 3.2 + */ + public static String join(final float[] array, final char delimiter) { + if (array == null) { + return null; + } + return join(array, delimiter, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)          = null
+     * StringUtils.join([], *)            = ""
+     * StringUtils.join([null], *)        = ""
+     * StringUtils.join([1, 2, 3], ';')   = "1;2;3"
+     * StringUtils.join([1, 2, 3], null)  = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @param startIndex + * the first index to start joining from. It is an error to pass in a start index past the end of the + * array. + * @param endIndex + * the index to stop joining from (exclusive). It is an error to pass in an end index past the end of + * the array. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final float[] array, final char delimiter, final int startIndex, final int endIndex) { + // See StringUtilsJoinBenchmark + if (array == null) { + return null; + } + final int count = endIndex - startIndex; + if (count <= 0) { + return EMPTY; + } + final byte maxElementChars = 12; // "3.4028235E38" + final StringBuilder stringBuilder = capacity(count, maxElementChars); + stringBuilder.append(array[startIndex]); + for (int i = startIndex + 1; i < endIndex; i++) { + stringBuilder.append(delimiter).append(array[i]); + } + return stringBuilder.toString(); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)          = null
+     * StringUtils.join([], *)            = ""
+     * StringUtils.join([null], *)        = ""
+     * StringUtils.join([1, 2, 3], ';')   = "1;2;3"
+     * StringUtils.join([1, 2, 3], null)  = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param separator + * the separator character to use. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final int[] array, final char separator) { + if (array == null) { + return null; + } + return join(array, separator, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)          = null
+     * StringUtils.join([], *)            = ""
+     * StringUtils.join([null], *)        = ""
+     * StringUtils.join([1, 2, 3], ';')   = "1;2;3"
+     * StringUtils.join([1, 2, 3], null)  = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @param startIndex + * the first index to start joining from. It is an error to pass in a start index past the end of the + * array. + * @param endIndex + * the index to stop joining from (exclusive). It is an error to pass in an end index past the end of + * the array. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final int[] array, final char delimiter, final int startIndex, final int endIndex) { + // See StringUtilsJoinBenchmark + if (array == null) { + return null; + } + final int count = endIndex - startIndex; + if (count <= 0) { + return EMPTY; + } + final byte maxElementChars = 11; // "-2147483648" + final StringBuilder stringBuilder = capacity(count, maxElementChars); + stringBuilder.append(array[startIndex]); + for (int i = startIndex + 1; i < endIndex; i++) { + stringBuilder.append(delimiter).append(array[i]); + } + return stringBuilder.toString(); + } + + /** + * Joins the elements of the provided {@link Iterable} into a single String containing the provided elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the iteration are represented by empty strings. + *

+ * + *

+ * See the examples here: {@link #join(Object[],char)}. + *

+ * + * @param iterable the {@link Iterable} providing the values to join together, may be null. + * @param separator the separator character to use. + * @return the joined String, {@code null} if null iterator input. + * @since 2.3 + */ + public static String join(final Iterable iterable, final char separator) { + return iterable != null ? join(iterable.iterator(), separator) : null; + } + + /** + * Joins the elements of the provided {@link Iterable} into a single String containing the provided elements. + * + *

+ * No delimiter is added before or after the list. A {@code null} separator is the same as an empty String (""). + *

+ * + *

+ * See the examples here: {@link #join(Object[],String)}. + *

+ * + * @param iterable the {@link Iterable} providing the values to join together, may be null. + * @param separator the separator character to use, null treated as "". + * @return the joined String, {@code null} if null iterator input. + * @since 2.3 + */ + public static String join(final Iterable iterable, final String separator) { + return iterable != null ? join(iterable.iterator(), separator) : null; + } + + /** + * Joins the elements of the provided {@link Iterator} into a single String containing the provided elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the iteration are represented by empty strings. + *

+ * + *

+ * See the examples here: {@link #join(Object[],char)}. + *

+ * + * @param iterator the {@link Iterator} of values to join together, may be null. + * @param separator the separator character to use. + * @return the joined String, {@code null} if null iterator input. + * @since 2.0 + */ + public static String join(final Iterator iterator, final char separator) { + // handle null, zero and one elements before building a buffer + if (iterator == null) { + return null; + } + if (!iterator.hasNext()) { + return EMPTY; + } + return Streams.of(iterator).collect(LangCollectors.joining(ObjectUtils.toString(String.valueOf(separator)), EMPTY, EMPTY, ObjectUtils::toString)); + } + + /** + * Joins the elements of the provided {@link Iterator} into a single String containing the provided elements. + * + *

+ * No delimiter is added before or after the list. A {@code null} separator is the same as an empty String (""). + *

+ * + *

+ * See the examples here: {@link #join(Object[],String)}. + *

+ * + * @param iterator the {@link Iterator} of values to join together, may be null. + * @param separator the separator character to use, null treated as "". + * @return the joined String, {@code null} if null iterator input. + */ + public static String join(final Iterator iterator, final String separator) { + // handle null, zero and one elements before building a buffer + if (iterator == null) { + return null; + } + if (!iterator.hasNext()) { + return EMPTY; + } + return Streams.of(iterator).collect(LangCollectors.joining(ObjectUtils.toString(separator), EMPTY, EMPTY, ObjectUtils::toString)); + } + + /** + * Joins the elements of the provided {@link List} into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)               = null
+     * StringUtils.join([], *)                 = ""
+     * StringUtils.join([null], *)             = ""
+     * StringUtils.join(["a", "b", "c"], ';')  = "a;b;c"
+     * StringUtils.join(["a", "b", "c"], null) = "abc"
+     * StringUtils.join([null, "", "a"], ';')  = ";;a"
+     * 
+ * + * @param list the {@link List} of values to join together, may be null. + * @param separator the separator character to use. + * @param startIndex the first index to start joining from. It is an error to pass in a start index past the end of the list. + * @param endIndex the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the list. + * @return the joined String, {@code null} if null list input. + * @since 3.8 + */ + public static String join(final List list, final char separator, final int startIndex, final int endIndex) { + if (list == null) { + return null; + } + final int noOfItems = endIndex - startIndex; + if (noOfItems <= 0) { + return EMPTY; + } + final List subList = list.subList(startIndex, endIndex); + return join(subList.iterator(), separator); + } + + /** + * Joins the elements of the provided {@link List} into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)               = null
+     * StringUtils.join([], *)                 = ""
+     * StringUtils.join([null], *)             = ""
+     * StringUtils.join(["a", "b", "c"], ';')  = "a;b;c"
+     * StringUtils.join(["a", "b", "c"], null) = "abc"
+     * StringUtils.join([null, "", "a"], ';')  = ";;a"
+     * 
+ * + * @param list the {@link List} of values to join together, may be null. + * @param separator the separator character to use. + * @param startIndex the first index to start joining from. It is an error to pass in a start index past the end of the list. + * @param endIndex the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the list. + * @return the joined String, {@code null} if null list input. + * @since 3.8 + */ + public static String join(final List list, final String separator, final int startIndex, final int endIndex) { + if (list == null) { + return null; + } + final int noOfItems = endIndex - startIndex; + if (noOfItems <= 0) { + return EMPTY; + } + final List subList = list.subList(startIndex, endIndex); + return join(subList.iterator(), separator); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)               = null
+     * StringUtils.join([], *)                 = ""
+     * StringUtils.join([null], *)             = ""
+     * StringUtils.join([1, 2, 3], ';')  = "1;2;3"
+     * StringUtils.join([1, 2, 3], null) = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param separator + * the separator character to use. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final long[] array, final char separator) { + if (array == null) { + return null; + } + return join(array, separator, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)               = null
+     * StringUtils.join([], *)                 = ""
+     * StringUtils.join([null], *)             = ""
+     * StringUtils.join([1, 2, 3], ';')  = "1;2;3"
+     * StringUtils.join([1, 2, 3], null) = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @param startIndex + * the first index to start joining from. It is an error to pass in a start index past the end of the + * array. + * @param endIndex + * the index to stop joining from (exclusive). It is an error to pass in an end index past the end of + * the array. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final long[] array, final char delimiter, final int startIndex, final int endIndex) { + // See StringUtilsJoinBenchmark + if (array == null) { + return null; + } + final int count = endIndex - startIndex; + if (count <= 0) { + return EMPTY; + } + final byte maxElementChars = 20; // "-9223372036854775808" + final StringBuilder stringBuilder = capacity(count, maxElementChars); + stringBuilder.append(array[startIndex]); + for (int i = startIndex + 1; i < endIndex; i++) { + stringBuilder.append(delimiter).append(array[i]); + } + return stringBuilder.toString(); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)               = null
+     * StringUtils.join([], *)                 = ""
+     * StringUtils.join([null], *)             = ""
+     * StringUtils.join(["a", "b", "c"], ';')  = "a;b;c"
+     * StringUtils.join(["a", "b", "c"], null) = "abc"
+     * StringUtils.join([null, "", "a"], ';')  = ";;a"
+     * 
+ * + * @param array the array of values to join together, may be null. + * @param delimiter the separator character to use. + * @return the joined String, {@code null} if null array input. + * @since 2.0 + */ + public static String join(final Object[] array, final char delimiter) { + if (array == null) { + return null; + } + return join(array, delimiter, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)               = null
+     * StringUtils.join([], *)                 = ""
+     * StringUtils.join([null], *)             = ""
+     * StringUtils.join(["a", "b", "c"], ';')  = "a;b;c"
+     * StringUtils.join(["a", "b", "c"], null) = "abc"
+     * StringUtils.join([null, "", "a"], ';')  = ";;a"
+     * 
+ * + * @param array the array of values to join together, may be null. + * @param delimiter the separator character to use. + * @param startIndex the first index to start joining from. It is an error to pass in a start index past the end of the array. + * @param endIndex the index to stop joining from (exclusive). It is an error to pass in an end index past the end of the array. + * @return the joined String, {@code null} if null array input. + * @since 2.0 + */ + public static String join(final Object[] array, final char delimiter, final int startIndex, final int endIndex) { + return join(array, String.valueOf(delimiter), startIndex, endIndex); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. A {@code null} separator is the same as an empty String (""). Null objects or empty strings within the + * array are represented by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)                = null
+     * StringUtils.join([], *)                  = ""
+     * StringUtils.join([null], *)              = ""
+     * StringUtils.join(["a", "b", "c"], "--")  = "a--b--c"
+     * StringUtils.join(["a", "b", "c"], null)  = "abc"
+     * StringUtils.join(["a", "b", "c"], "")    = "abc"
+     * StringUtils.join([null, "", "a"], ',')   = ",,a"
+     * 
+ * + * @param array the array of values to join together, may be null. + * @param delimiter the separator character to use, null treated as "". + * @return the joined String, {@code null} if null array input. + */ + public static String join(final Object[] array, final String delimiter) { + return array != null ? join(array, ObjectUtils.toString(delimiter), 0, array.length) : null; + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. A {@code null} separator is the same as an empty String (""). Null objects or empty strings within the + * array are represented by empty strings. + *

+ * + *
+     * StringUtils.join(null, *, *, *)                = null
+     * StringUtils.join([], *, *, *)                  = ""
+     * StringUtils.join([null], *, *, *)              = ""
+     * StringUtils.join(["a", "b", "c"], "--", 0, 3)  = "a--b--c"
+     * StringUtils.join(["a", "b", "c"], "--", 1, 3)  = "b--c"
+     * StringUtils.join(["a", "b", "c"], "--", 2, 3)  = "c"
+     * StringUtils.join(["a", "b", "c"], "--", 2, 2)  = ""
+     * StringUtils.join(["a", "b", "c"], null, 0, 3)  = "abc"
+     * StringUtils.join(["a", "b", "c"], "", 0, 3)    = "abc"
+     * StringUtils.join([null, "", "a"], ',', 0, 3)   = ",,a"
+     * 
+ * + * @param array the array of values to join together, may be null. + * @param delimiter the separator character to use, null treated as "". + * @param startIndex the first index to start joining from. + * @param endIndex the index to stop joining from (exclusive). + * @return the joined String, {@code null} if null array input; or the empty string if {@code endIndex - startIndex <= 0}. The number of joined entries is + * given by {@code endIndex - startIndex}. + * @throws ArrayIndexOutOfBoundsException ife
+ * {@code startIndex < 0} or
+ * {@code startIndex >= array.length()} or
+ * {@code endIndex < 0} or
+ * {@code endIndex > array.length()} + */ + public static String join(final Object[] array, final String delimiter, final int startIndex, final int endIndex) { + return array != null ? Streams.of(array).skip(startIndex).limit(Math.max(0, endIndex - startIndex)) + .collect(LangCollectors.joining(delimiter, EMPTY, EMPTY, ObjectUtils::toString)) : null; + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)          = null
+     * StringUtils.join([], *)            = ""
+     * StringUtils.join([null], *)        = ""
+     * StringUtils.join([1, 2, 3], ';')   = "1;2;3"
+     * StringUtils.join([1, 2, 3], null)  = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final short[] array, final char delimiter) { + if (array == null) { + return null; + } + return join(array, delimiter, 0, array.length); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No delimiter is added before or after the list. Null objects or empty strings within the array are represented + * by empty strings. + *

+ * + *
+     * StringUtils.join(null, *)          = null
+     * StringUtils.join([], *)            = ""
+     * StringUtils.join([null], *)        = ""
+     * StringUtils.join([1, 2, 3], ';')   = "1;2;3"
+     * StringUtils.join([1, 2, 3], null)  = "123"
+     * 
+ * + * @param array + * the array of values to join together, may be null. + * @param delimiter + * the separator character to use. + * @param startIndex + * the first index to start joining from. It is an error to pass in a start index past the end of the + * array. + * @param endIndex + * the index to stop joining from (exclusive). It is an error to pass in an end index past the end of + * the array. + * @return the joined String, {@code null} if null array input. + * @since 3.2 + */ + public static String join(final short[] array, final char delimiter, final int startIndex, final int endIndex) { + // See StringUtilsJoinBenchmark + if (array == null) { + return null; + } + final int count = endIndex - startIndex; + if (count <= 0) { + return EMPTY; + } + final byte maxElementChars = 6; // "-32768" + final StringBuilder stringBuilder = capacity(count, maxElementChars); + stringBuilder.append(array[startIndex]); + for (int i = startIndex + 1; i < endIndex; i++) { + stringBuilder.append(delimiter).append(array[i]); + } + return stringBuilder.toString(); + } + + /** + * Joins the elements of the provided array into a single String containing the provided list of elements. + * + *

+ * No separator is added to the joined String. Null objects or empty strings within the array are represented by empty strings. + *

+ * + *
+     * StringUtils.join(null)            = null
+     * StringUtils.join([])              = ""
+     * StringUtils.join([null])          = ""
+     * StringUtils.join("a", "b", "c")   = "abc"
+     * StringUtils.join(null, "", "a")   = "a"
+     * 
+ * + * @param the specific type of values to join together. + * @param elements the values to join together, may be null. + * @return the joined String, {@code null} if null array input. + * @since 2.0 + * @since 3.0 Changed signature to use varargs + */ + @SafeVarargs + public static String join(final T... elements) { + return join(elements, null); + } + + /** + * Joins the elements of the provided varargs into a single String containing the provided elements. + * + *

+ * No delimiter is added before or after the list. {@code null} elements and separator are treated as empty Strings (""). + *

+ * + *
+     * StringUtils.joinWith(",", "a", "b")        = "a,b"
+     * StringUtils.joinWith(",", "a", "b","")     = "a,b,"
+     * StringUtils.joinWith(",", "a", null, "b")  = "a,,b"
+     * StringUtils.joinWith(null, "a", "b")       = "ab"
+     * 
+ * + * @param delimiter the separator character to use, null treated as "". + * @param array the varargs providing the values to join together. {@code null} elements are treated as "". + * @return the joined String. + * @throws IllegalArgumentException if a null varargs is provided. + * @since 3.5 + */ + public static String joinWith(final String delimiter, final Object... array) { + if (array == null) { + throw new IllegalArgumentException("Object varargs must not be null"); + } + return join(array, delimiter); + } + + /** + * Finds the last index within a CharSequence, handling {@code null}. This method uses {@link String#lastIndexOf(String)} if possible. + * + *

+ * A {@code null} CharSequence will return {@code -1}. + *

+ * + *
+     * StringUtils.lastIndexOf(null, *)          = -1
+     * StringUtils.lastIndexOf(*, null)          = -1
+     * StringUtils.lastIndexOf("", "")           = 0
+     * StringUtils.lastIndexOf("aabaabaa", "a")  = 7
+     * StringUtils.lastIndexOf("aabaabaa", "b")  = 5
+     * StringUtils.lastIndexOf("aabaabaa", "ab") = 4
+     * StringUtils.lastIndexOf("aabaabaa", "")   = 8
+     * 
+ * + * @param seq the CharSequence to check, may be null. + * @param searchSeq the CharSequence to find, may be null. + * @return the last index of the search String, -1 if no match or {@code null} string input. + * @since 2.0 + * @since 3.0 Changed signature from lastIndexOf(String, String) to lastIndexOf(CharSequence, CharSequence) + * @deprecated Use {@link Strings#lastIndexOf(CharSequence, CharSequence) Strings.CS.lastIndexOf(CharSequence, CharSequence)}. + */ + @Deprecated + public static int lastIndexOf(final CharSequence seq, final CharSequence searchSeq) { + return Strings.CS.lastIndexOf(seq, searchSeq); + } + + /** + * Finds the last index within a CharSequence, handling {@code null}. This method uses {@link String#lastIndexOf(String, int)} if possible. + * + *

+ * A {@code null} CharSequence will return {@code -1}. A negative start position returns {@code -1}. An empty ("") search CharSequence always matches unless + * the start position is negative. A start position greater than the string length searches the whole string. The search starts at the startPos and works + * backwards; matches starting after the start position are ignored. + *

+ * + *
+     * StringUtils.lastIndexOf(null, *, *)          = -1
+     * StringUtils.lastIndexOf(*, null, *)          = -1
+     * StringUtils.lastIndexOf("aabaabaa", "a", 8)  = 7
+     * StringUtils.lastIndexOf("aabaabaa", "b", 8)  = 5
+     * StringUtils.lastIndexOf("aabaabaa", "ab", 8) = 4
+     * StringUtils.lastIndexOf("aabaabaa", "b", 9)  = 5
+     * StringUtils.lastIndexOf("aabaabaa", "b", -1) = -1
+     * StringUtils.lastIndexOf("aabaabaa", "a", 0)  = 0
+     * StringUtils.lastIndexOf("aabaabaa", "b", 0)  = -1
+     * StringUtils.lastIndexOf("aabaabaa", "b", 1)  = -1
+     * StringUtils.lastIndexOf("aabaabaa", "b", 2)  = 2
+     * StringUtils.lastIndexOf("aabaabaa", "ba", 2)  = 2
+     * 
+ * + * @param seq the CharSequence to check, may be null. + * @param searchSeq the CharSequence to find, may be null. + * @param startPos the start position, negative treated as zero. + * @return the last index of the search CharSequence (always ≤ startPos), -1 if no match or {@code null} string input. + * @since 2.0 + * @since 3.0 Changed signature from lastIndexOf(String, String, int) to lastIndexOf(CharSequence, CharSequence, int) + * @deprecated Use {@link Strings#lastIndexOf(CharSequence, CharSequence, int) Strings.CS.lastIndexOf(CharSequence, CharSequence, int)}. + */ + @Deprecated + public static int lastIndexOf(final CharSequence seq, final CharSequence searchSeq, final int startPos) { + return Strings.CS.lastIndexOf(seq, searchSeq, startPos); + } + + /** + * Returns the index within {@code seq} of the last occurrence of the specified character. For values of {@code searchChar} in the range from 0 to 0xFFFF + * (inclusive), the index (in Unicode code units) returned is the largest value k such that: + * + *
+     * this.charAt(k) == searchChar
+     * 
+ * + *

+ * is true. For other values of {@code searchChar}, it is the largest value k such that: + *

+ * + *
+     * this.codePointAt(k) == searchChar
+     * 
+ * + *

+ * is true. In either case, if no such character occurs in this string, then {@code -1} is returned. Furthermore, a {@code null} or empty ("") + * {@link CharSequence} will return {@code -1}. The {@code seq} {@link CharSequence} object is searched backwards starting at the last character. + *

+ * + *
+     * StringUtils.lastIndexOf(null, *)         = -1
+     * StringUtils.lastIndexOf("", *)           = -1
+     * StringUtils.lastIndexOf("aabaabaa", 'a') = 7
+     * StringUtils.lastIndexOf("aabaabaa", 'b') = 5
+     * 
+ * + * @param seq the {@link CharSequence} to check, may be null. + * @param searchChar the character to find. + * @return the last index of the search character, -1 if no match or {@code null} string input. + * @since 2.0 + * @since 3.0 Changed signature from lastIndexOf(String, int) to lastIndexOf(CharSequence, int) + * @since 3.6 Updated {@link CharSequenceUtils} call to behave more like {@link String} + */ + public static int lastIndexOf(final CharSequence seq, final int searchChar) { + if (isEmpty(seq)) { + return INDEX_NOT_FOUND; + } + return CharSequenceUtils.lastIndexOf(seq, searchChar, seq.length()); + } + + /** + * Returns the index within {@code seq} of the last occurrence of the specified character, searching backward starting at the specified index. For values of + * {@code searchChar} in the range from 0 to 0xFFFF (inclusive), the index returned is the largest value k such that: + * + *
+     * (this.charAt(k) == searchChar) && (k <= startPos)
+     * 
+ * + *

+ * is true. For other values of {@code searchChar}, it is the largest value k such that: + *

+ * + *
+     * (this.codePointAt(k) == searchChar) && (k <= startPos)
+     * 
+ * + *

+ * is true. In either case, if no such character occurs in {@code seq} at or before position {@code startPos}, then {@code -1} is returned. Furthermore, a + * {@code null} or empty ("") {@link CharSequence} will return {@code -1}. A start position greater than the string length searches the whole string. The + * search starts at the {@code startPos} and works backwards; matches starting after the start position are ignored. + *

+ * + *

+ * All indices are specified in {@code char} values (Unicode code units). + *

+ * + *
+     * StringUtils.lastIndexOf(null, *, *)          = -1
+     * StringUtils.lastIndexOf("", *,  *)           = -1
+     * StringUtils.lastIndexOf("aabaabaa", 'b', 8)  = 5
+     * StringUtils.lastIndexOf("aabaabaa", 'b', 4)  = 2
+     * StringUtils.lastIndexOf("aabaabaa", 'b', 0)  = -1
+     * StringUtils.lastIndexOf("aabaabaa", 'b', 9)  = 5
+     * StringUtils.lastIndexOf("aabaabaa", 'b', -1) = -1
+     * StringUtils.lastIndexOf("aabaabaa", 'a', 0)  = 0
+     * 
+ * + * @param seq the CharSequence to check, may be null. + * @param searchChar the character to find. + * @param startPos the start position. + * @return the last index of the search character (always ≤ startPos), -1 if no match or {@code null} string input. + * @since 2.0 + * @since 3.0 Changed signature from lastIndexOf(String, int, int) to lastIndexOf(CharSequence, int, int) + */ + public static int lastIndexOf(final CharSequence seq, final int searchChar, final int startPos) { + if (isEmpty(seq)) { + return INDEX_NOT_FOUND; + } + return CharSequenceUtils.lastIndexOf(seq, searchChar, startPos); + } + + /** + * Finds the latest index of any substring in a set of potential substrings. + * + *

+ * A {@code null} CharSequence will return {@code -1}. A {@code null} search array will return {@code -1}. A {@code null} or zero length search array entry + * will be ignored, but a search array containing "" will return the length of {@code str} if {@code str} is not null. This method uses + * {@link String#indexOf(String)} if possible + *

+ * + *
+     * StringUtils.lastIndexOfAny(null, *)                    = -1
+     * StringUtils.lastIndexOfAny(*, null)                    = -1
+     * StringUtils.lastIndexOfAny(*, [])                      = -1
+     * StringUtils.lastIndexOfAny(*, [null])                  = -1
+     * StringUtils.lastIndexOfAny("zzabyycdxx", ["ab", "cd"]) = 6
+     * StringUtils.lastIndexOfAny("zzabyycdxx", ["cd", "ab"]) = 6
+     * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn", "op"]) = -1
+     * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn", "op"]) = -1
+     * StringUtils.lastIndexOfAny("zzabyycdxx", ["mn", ""])   = 10
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStrs the CharSequences to search for, may be null. + * @return the last index of any of the CharSequences, -1 if no match. + * @since 3.0 Changed signature from lastIndexOfAny(String, String[]) to lastIndexOfAny(CharSequence, CharSequence) + */ + public static int lastIndexOfAny(final CharSequence str, final CharSequence... searchStrs) { + if (str == null || searchStrs == null) { + return INDEX_NOT_FOUND; + } + int ret = INDEX_NOT_FOUND; + int tmp; + for (final CharSequence search : searchStrs) { + if (search == null) { + continue; + } + tmp = CharSequenceUtils.lastIndexOf(str, search, str.length()); + if (tmp > ret) { + ret = tmp; + } + } + return ret; + } + + /** + * Case in-sensitive find of the last index within a CharSequence. + * + *

+ * A {@code null} CharSequence will return {@code -1}. A negative start position returns {@code -1}. An empty ("") search CharSequence always matches unless + * the start position is negative. A start position greater than the string length searches the whole string. + *

+ * + *
+     * StringUtils.lastIndexOfIgnoreCase(null, *)          = -1
+     * StringUtils.lastIndexOfIgnoreCase(*, null)          = -1
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "A")  = 7
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B")  = 5
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "AB") = 4
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStr the CharSequence to find, may be null. + * @return the first index of the search CharSequence, -1 if no match or {@code null} string input. + * @since 2.5 + * @since 3.0 Changed signature from lastIndexOfIgnoreCase(String, String) to lastIndexOfIgnoreCase(CharSequence, CharSequence) + * @deprecated Use {@link Strings#lastIndexOf(CharSequence, CharSequence) Strings.CI.lastIndexOf(CharSequence, CharSequence)}. + */ + @Deprecated + public static int lastIndexOfIgnoreCase(final CharSequence str, final CharSequence searchStr) { + return Strings.CI.lastIndexOf(str, searchStr); + } + + /** + * Case in-sensitive find of the last index within a CharSequence from the specified position. + * + *

+ * A {@code null} CharSequence will return {@code -1}. A negative start position returns {@code -1}. An empty ("") search CharSequence always matches unless + * the start position is negative. A start position greater than the string length searches the whole string. The search starts at the startPos and works + * backwards; matches starting after the start position are ignored. + *

+ * + *
+     * StringUtils.lastIndexOfIgnoreCase(null, *, *)          = -1
+     * StringUtils.lastIndexOfIgnoreCase(*, null, *)          = -1
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "A", 8)  = 7
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B", 8)  = 5
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "AB", 8) = 4
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B", 9)  = 5
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B", -1) = -1
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "A", 0)  = 0
+     * StringUtils.lastIndexOfIgnoreCase("aabaabaa", "B", 0)  = -1
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStr the CharSequence to find, may be null. + * @param startPos the start position. + * @return the last index of the search CharSequence (always ≤ startPos), -1 if no match or {@code null} input. + * @since 2.5 + * @since 3.0 Changed signature from lastIndexOfIgnoreCase(String, String, int) to lastIndexOfIgnoreCase(CharSequence, CharSequence, int) + * @deprecated Use {@link Strings#lastIndexOf(CharSequence, CharSequence, int) Strings.CI.lastIndexOf(CharSequence, CharSequence, int)}. + */ + @Deprecated + public static int lastIndexOfIgnoreCase(final CharSequence str, final CharSequence searchStr, final int startPos) { + return Strings.CI.lastIndexOf(str, searchStr, startPos); + } + + /** + * Finds the n-th last index within a String, handling {@code null}. This method uses {@link String#lastIndexOf(String)}. + * + *

+ * A {@code null} String will return {@code -1}. + *

+ * + *
+     * StringUtils.lastOrdinalIndexOf(null, *, *)          = -1
+     * StringUtils.lastOrdinalIndexOf(*, null, *)          = -1
+     * StringUtils.lastOrdinalIndexOf("", "", *)           = 0
+     * StringUtils.lastOrdinalIndexOf("aabaabaa", "a", 1)  = 7
+     * StringUtils.lastOrdinalIndexOf("aabaabaa", "a", 2)  = 6
+     * StringUtils.lastOrdinalIndexOf("aabaabaa", "b", 1)  = 5
+     * StringUtils.lastOrdinalIndexOf("aabaabaa", "b", 2)  = 2
+     * StringUtils.lastOrdinalIndexOf("aabaabaa", "ab", 1) = 4
+     * StringUtils.lastOrdinalIndexOf("aabaabaa", "ab", 2) = 1
+     * StringUtils.lastOrdinalIndexOf("aabaabaa", "", 1)   = 8
+     * StringUtils.lastOrdinalIndexOf("aabaabaa", "", 2)   = 8
+     * 
+ * + *

+ * Note that 'tail(CharSequence str, int n)' may be implemented as: + *

+ * + *
+     * str.substring(lastOrdinalIndexOf(str, "\n", n) + 1)
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStr the CharSequence to find, may be null. + * @param ordinal the n-th last {@code searchStr} to find. + * @return the n-th last index of the search CharSequence, {@code -1} ({@code INDEX_NOT_FOUND}) if no match or {@code null} string input. + * @since 2.5 + * @since 3.0 Changed signature from lastOrdinalIndexOf(String, String, int) to lastOrdinalIndexOf(CharSequence, CharSequence, int) + */ + public static int lastOrdinalIndexOf(final CharSequence str, final CharSequence searchStr, final int ordinal) { + return ordinalIndexOf(str, searchStr, ordinal, true); + } + + /** + * Gets the leftmost {@code len} characters of a String. + * + *

+ * If {@code len} characters are not available, or the String is {@code null}, the String will be returned without an exception. An empty String is returned + * if len is negative. + *

+ * + *
+     * StringUtils.left(null, *)    = null
+     * StringUtils.left(*, -ve)     = ""
+     * StringUtils.left("", *)      = ""
+     * StringUtils.left("abc", 0)   = ""
+     * StringUtils.left("abc", 2)   = "ab"
+     * StringUtils.left("abc", 4)   = "abc"
+     * 
+ * + * @param str the String to get the leftmost characters from, may be null. + * @param len the length of the required String. + * @return the leftmost characters, {@code null} if null String input. + */ + public static String left(final String str, final int len) { + if (str == null) { + return null; + } + if (len < 0) { + return EMPTY; + } + if (str.length() <= len) { + return str; + } + return str.substring(0, len); + } + + /** + * Left pad a String with spaces (' '). + * + *

+ * The String is padded to the size of {@code size}. + *

+ * + *
+     * StringUtils.leftPad(null, *)   = null
+     * StringUtils.leftPad("", 3)     = "   "
+     * StringUtils.leftPad("bat", 3)  = "bat"
+     * StringUtils.leftPad("bat", 5)  = "  bat"
+     * StringUtils.leftPad("bat", 1)  = "bat"
+     * StringUtils.leftPad("bat", -1) = "bat"
+     * 
+ * + * @param str the String to pad out, may be null. + * @param size the size to pad to. + * @return left padded String or original String if no padding is necessary, {@code null} if null String input. + */ + public static String leftPad(final String str, final int size) { + return leftPad(str, size, ' '); + } + + /** + * Left pad a String with a specified character. + * + *

+ * Pad to a size of {@code size}. + *

+ * + *
+     * StringUtils.leftPad(null, *, *)     = null
+     * StringUtils.leftPad("", 3, 'z')     = "zzz"
+     * StringUtils.leftPad("bat", 3, 'z')  = "bat"
+     * StringUtils.leftPad("bat", 5, 'z')  = "zzbat"
+     * StringUtils.leftPad("bat", 1, 'z')  = "bat"
+     * StringUtils.leftPad("bat", -1, 'z') = "bat"
+     * 
+ * + * @param str the String to pad out, may be null. + * @param size the size to pad to. + * @param padChar the character to pad with. + * @return left padded String or original String if no padding is necessary, {@code null} if null String input. + * @since 2.0 + */ + public static String leftPad(final String str, final int size, final char padChar) { + if (str == null) { + return null; + } + final int pads = size - str.length(); + if (pads <= 0) { + return str; // returns original String when possible + } + if (pads > PAD_LIMIT) { + return leftPad(str, size, String.valueOf(padChar)); + } + return repeat(padChar, pads).concat(str); + } + + /** + * Left pad a String with a specified String. + * + *

+ * Pad to a size of {@code size}. + *

+ * + *
+     * StringUtils.leftPad(null, *, *)      = null
+     * StringUtils.leftPad("", 3, "z")      = "zzz"
+     * StringUtils.leftPad("bat", 3, "yz")  = "bat"
+     * StringUtils.leftPad("bat", 5, "yz")  = "yzbat"
+     * StringUtils.leftPad("bat", 8, "yz")  = "yzyzybat"
+     * StringUtils.leftPad("bat", 1, "yz")  = "bat"
+     * StringUtils.leftPad("bat", -1, "yz") = "bat"
+     * StringUtils.leftPad("bat", 5, null)  = "  bat"
+     * StringUtils.leftPad("bat", 5, "")    = "  bat"
+     * 
+ * + * @param str the String to pad out, may be null. + * @param size the size to pad to. + * @param padStr the String to pad with, null or empty treated as single space. + * @return left padded String or original String if no padding is necessary, {@code null} if null String input. + */ + public static String leftPad(final String str, final int size, String padStr) { + if (str == null) { + return null; + } + if (isEmpty(padStr)) { + padStr = SPACE; + } + final int padLen = padStr.length(); + final int strLen = str.length(); + final int pads = size - strLen; + if (pads <= 0) { + return str; // returns original String when possible + } + if (padLen == 1 && pads <= PAD_LIMIT) { + return leftPad(str, size, padStr.charAt(0)); + } + if (pads == padLen) { + return padStr.concat(str); + } + if (pads < padLen) { + return padStr.substring(0, pads).concat(str); + } + final char[] padding = new char[pads]; + final char[] padChars = padStr.toCharArray(); + for (int i = 0; i < pads; i++) { + padding[i] = padChars[i % padLen]; + } + return new String(padding).concat(str); + } + + /** + * Gets a CharSequence length or {@code 0} if the CharSequence is {@code null}. + * + * @param cs a CharSequence or {@code null}. + * @return CharSequence length or {@code 0} if the CharSequence is {@code null}. + * @since 2.4 + * @since 3.0 Changed signature from length(String) to length(CharSequence) + */ + public static int length(final CharSequence cs) { + return cs == null ? 0 : cs.length(); + } + + /** + * Converts a String to lower case as per {@link String#toLowerCase()}. + * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.lowerCase(null)  = null
+     * StringUtils.lowerCase("")    = ""
+     * StringUtils.lowerCase("aBc") = "abc"
+     * 
+ * + *

+ * Note: As described in the documentation for {@link String#toLowerCase()}, the result of this method is affected by the current locale. + * For platform-independent case transformations, the method {@link #lowerCase(String, Locale)} should be used with a specific locale (e.g. + * {@link Locale#ENGLISH}). + *

+ * + * @param str the String to lower case, may be null. + * @return the lower cased String, {@code null} if null String input. + */ + public static String lowerCase(final String str) { + if (str == null) { + return null; + } + return str.toLowerCase(); + } + + /** + * Converts a String to lower case as per {@link String#toLowerCase(Locale)}. + * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.lowerCase(null, Locale.ENGLISH)  = null
+     * StringUtils.lowerCase("", Locale.ENGLISH)    = ""
+     * StringUtils.lowerCase("aBc", Locale.ENGLISH) = "abc"
+     * 
+ * + * @param str the String to lower case, may be null. + * @param locale the locale that defines the case transformation rules, must not be null. + * @return the lower cased String, {@code null} if null String input. + * @since 2.5 + */ + public static String lowerCase(final String str, final Locale locale) { + if (str == null) { + return null; + } + return str.toLowerCase(LocaleUtils.toLocale(locale)); + } + + private static int[] matches(final CharSequence first, final CharSequence second) { + final CharSequence max; + final CharSequence min; + if (first.length() > second.length()) { + max = first; + min = second; + } else { + max = second; + min = first; + } + final int range = Math.max(max.length() / 2 - 1, 0); + final int[] matchIndexes = ArrayFill.fill(new int[min.length()], -1); + final boolean[] matchFlags = new boolean[max.length()]; + int matches = 0; + for (int mi = 0; mi < min.length(); mi++) { + final char c1 = min.charAt(mi); + for (int xi = Math.max(mi - range, 0), xn = Math.min(mi + range + 1, max.length()); xi < xn; xi++) { + if (!matchFlags[xi] && c1 == max.charAt(xi)) { + matchIndexes[mi] = xi; + matchFlags[xi] = true; + matches++; + break; + } + } + } + final char[] ms1 = new char[matches]; + final char[] ms2 = new char[matches]; + for (int i = 0, si = 0; i < min.length(); i++) { + if (matchIndexes[i] != -1) { + ms1[si] = min.charAt(i); + si++; + } + } + for (int i = 0, si = 0; i < max.length(); i++) { + if (matchFlags[i]) { + ms2[si] = max.charAt(i); + si++; + } + } + int transpositions = 0; + for (int mi = 0; mi < ms1.length; mi++) { + if (ms1[mi] != ms2[mi]) { + transpositions++; + } + } + int prefix = 0; + for (int mi = 0; mi < min.length(); mi++) { + if (first.charAt(mi) != second.charAt(mi)) { + break; + } + prefix++; + } + return new int[] { matches, transpositions / 2, prefix, max.length() }; + } + + /** + * Gets {@code len} characters from the middle of a String. + * + *

+ * If {@code len} characters are not available, the remainder of the String will be returned without an exception. If the String is {@code null}, + * {@code null} will be returned. An empty String is returned if len is negative or exceeds the length of {@code str}. + *

+ * + *
+     * StringUtils.mid(null, *, *)    = null
+     * StringUtils.mid(*, *, -ve)     = ""
+     * StringUtils.mid("", 0, *)      = ""
+     * StringUtils.mid("abc", 0, 2)   = "ab"
+     * StringUtils.mid("abc", 0, 4)   = "abc"
+     * StringUtils.mid("abc", 2, 4)   = "c"
+     * StringUtils.mid("abc", 4, 2)   = ""
+     * StringUtils.mid("abc", -2, 2)  = "ab"
+     * 
+ * + * @param str the String to get the characters from, may be null. + * @param pos the position to start from, negative treated as zero. + * @param len the length of the required String. + * @return the middle characters, {@code null} if null String input. + */ + public static String mid(final String str, int pos, final int len) { + if (str == null) { + return null; + } + if (len < 0 || pos > str.length()) { + return EMPTY; + } + if (pos < 0) { + pos = 0; + } + if (str.length() <= pos + len) { + return str.substring(pos); + } + return str.substring(pos, pos + len); + } + + /** + * Similar to https://www.w3.org/TR/xpath/#function-normalize -space + * + *

+ * This function returns the argument string with whitespace normalized by using {@code {@link #trim(String)}} to remove leading and trailing whitespace and + * then replacing sequences of whitespace characters by a single space. + *

+ * In XML, whitespace characters are the same as those allowed by the S production, which is S ::= (#x20 | + * #x9 | #xD | #xA)+ + *

+ * Java's regexp pattern \s defines whitespace as [ \t\n\x0B\f\r] + *

+ *

+ * For reference: + *

+ *
    + *
  • \x0B = vertical tab
  • + *
  • \f = #xC = form feed
  • + *
  • #x20 = space
  • + *
  • #x9 = \t
  • + *
  • #xA = \n
  • + *
  • #xD = \r
  • + *
+ * + *

+ * The difference is that Java's whitespace includes vertical tab and form feed, which this function will also normalize. Additionally {@code {@link + * #trim(String)}} removes control characters (char <= 32) from both ends of this String. + *

+ * + * @param str the source String to normalize whitespaces from, may be null. + * @return the modified string with whitespace normalized, {@code null} if null String input. + * @see Pattern + * @see #trim(String) + * @see https://www.w3.org/TR/xpath/#function-normalize-space + * @since 3.0 + */ + public static String normalizeSpace(final String str) { + // LANG-1020: Improved performance significantly by normalizing manually instead of using regex + // See https://github.com/librucha/commons-lang-normalizespaces-benchmark for performance test + if (isEmpty(str)) { + return str; + } + final int size = str.length(); + final char[] newChars = new char[size]; + int count = 0; + int whitespacesCount = 0; + boolean startWhitespaces = true; + for (int i = 0; i < size; i++) { + final char actualChar = str.charAt(i); + final boolean isWhitespace = Character.isWhitespace(actualChar); + if (isWhitespace) { + if (whitespacesCount == 0 && !startWhitespaces) { + newChars[count++] = SPACE.charAt(0); + } + whitespacesCount++; + } else { + startWhitespaces = false; + newChars[count++] = actualChar == 160 ? 32 : actualChar; + whitespacesCount = 0; + } + } + if (startWhitespaces) { + return EMPTY; + } + return new String(newChars, 0, count - (whitespacesCount > 0 ? 1 : 0)).trim(); + } + + /** + * Finds the n-th index within a CharSequence, handling {@code null}. This method uses {@link String#indexOf(String)} if possible. + *

+ * Note: The code starts looking for a match at the start of the target, incrementing the starting index by one after each successful match + * (unless {@code searchStr} is an empty string, in which case the position is never incremented and {@code 0} is returned immediately). This means that + * matches may overlap. + *

+ *

+ * A {@code null} CharSequence will return {@code -1}. + *

+ * + *
+     * StringUtils.ordinalIndexOf(null, *, *)          = -1
+     * StringUtils.ordinalIndexOf(*, null, *)          = -1
+     * StringUtils.ordinalIndexOf("", "", *)           = 0
+     * StringUtils.ordinalIndexOf("aabaabaa", "a", 1)  = 0
+     * StringUtils.ordinalIndexOf("aabaabaa", "a", 2)  = 1
+     * StringUtils.ordinalIndexOf("aabaabaa", "b", 1)  = 2
+     * StringUtils.ordinalIndexOf("aabaabaa", "b", 2)  = 5
+     * StringUtils.ordinalIndexOf("aabaabaa", "ab", 1) = 1
+     * StringUtils.ordinalIndexOf("aabaabaa", "ab", 2) = 4
+     * StringUtils.ordinalIndexOf("aabaabaa", "", 1)   = 0
+     * StringUtils.ordinalIndexOf("aabaabaa", "", 2)   = 0
+     * 
+ * + *

+ * Matches may overlap: + *

+ * + *
+     * StringUtils.ordinalIndexOf("ababab", "aba", 1)   = 0
+     * StringUtils.ordinalIndexOf("ababab", "aba", 2)   = 2
+     * StringUtils.ordinalIndexOf("ababab", "aba", 3)   = -1
+     *
+     * StringUtils.ordinalIndexOf("abababab", "abab", 1) = 0
+     * StringUtils.ordinalIndexOf("abababab", "abab", 2) = 2
+     * StringUtils.ordinalIndexOf("abababab", "abab", 3) = 4
+     * StringUtils.ordinalIndexOf("abababab", "abab", 4) = -1
+     * 
+ * + *

+ * Note that 'head(CharSequence str, int n)' may be implemented as: + *

+ * + *
+     * str.substring(0, lastOrdinalIndexOf(str, "\n", n))
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param searchStr the CharSequence to find, may be null. + * @param ordinal the n-th {@code searchStr} to find. + * @return the n-th index of the search CharSequence, {@code -1} ({@code INDEX_NOT_FOUND}) if no match or {@code null} string input. + * @since 2.1 + * @since 3.0 Changed signature from ordinalIndexOf(String, String, int) to ordinalIndexOf(CharSequence, CharSequence, int) + */ + public static int ordinalIndexOf(final CharSequence str, final CharSequence searchStr, final int ordinal) { + return ordinalIndexOf(str, searchStr, ordinal, false); + } + + /** + * Finds the n-th index within a String, handling {@code null}. This method uses {@link String#indexOf(String)} if possible. + *

+ * Note that matches may overlap. + *

+ * + *

+ * A {@code null} CharSequence will return {@code -1}. + *

+ * + * @param str the CharSequence to check, may be null. + * @param searchStr the CharSequence to find, may be null. + * @param ordinal the n-th {@code searchStr} to find, overlapping matches are allowed. + * @param lastIndex true if lastOrdinalIndexOf() otherwise false if ordinalIndexOf(). + * @return the n-th index of the search CharSequence, {@code -1} ({@code INDEX_NOT_FOUND}) if no match or {@code null} string input. + */ + // Shared code between ordinalIndexOf(String, String, int) and lastOrdinalIndexOf(String, String, int) + private static int ordinalIndexOf(final CharSequence str, final CharSequence searchStr, final int ordinal, final boolean lastIndex) { + if (str == null || searchStr == null || ordinal <= 0) { + return INDEX_NOT_FOUND; + } + if (searchStr.length() == 0) { + return lastIndex ? str.length() : 0; + } + int found = 0; + // set the initial index beyond the end of the string + // this is to allow for the initial index decrement/increment + int index = lastIndex ? str.length() : INDEX_NOT_FOUND; + do { + if (lastIndex) { + index = CharSequenceUtils.lastIndexOf(str, searchStr, index - 1); // step backwards through string + } else { + index = CharSequenceUtils.indexOf(str, searchStr, index + 1); // step forwards through string + } + if (index < 0) { + return index; + } + found++; + } while (found < ordinal); + return index; + } + + /** + * Overlays part of a String with another String. + * + *

+ * A {@code null} string input returns {@code null}. A negative index is treated as zero. An index greater than the string length is treated as the string + * length. The start index is always the smaller of the two indices. + *

+ * + *
+     * StringUtils.overlay(null, *, *, *)            = null
+     * StringUtils.overlay("", "abc", 0, 0)          = "abc"
+     * StringUtils.overlay("abcdef", null, 2, 4)     = "abef"
+     * StringUtils.overlay("abcdef", "", 2, 4)       = "abef"
+     * StringUtils.overlay("abcdef", "", 4, 2)       = "abef"
+     * StringUtils.overlay("abcdef", "zzzz", 2, 4)   = "abzzzzef"
+     * StringUtils.overlay("abcdef", "zzzz", 4, 2)   = "abzzzzef"
+     * StringUtils.overlay("abcdef", "zzzz", -1, 4)  = "zzzzef"
+     * StringUtils.overlay("abcdef", "zzzz", 2, 8)   = "abzzzz"
+     * StringUtils.overlay("abcdef", "zzzz", -2, -3) = "zzzzabcdef"
+     * StringUtils.overlay("abcdef", "zzzz", 8, 10)  = "abcdefzzzz"
+     * 
+ * + * @param str the String to do overlaying in, may be null. + * @param overlay the String to overlay, may be null. + * @param start the position to start overlaying at. + * @param end the position to stop overlaying before. + * @return overlayed String, {@code null} if null String input. + * @since 2.0 + */ + public static String overlay(final String str, String overlay, int start, int end) { + if (str == null) { + return null; + } + if (overlay == null) { + overlay = EMPTY; + } + final int len = str.length(); + if (start < 0) { + start = 0; + } + if (start > len) { + start = len; + } + if (end < 0) { + end = 0; + } + if (end > len) { + end = len; + } + if (start > end) { + final int temp = start; + start = end; + end = temp; + } + return str.substring(0, start) + overlay + str.substring(end); + } + + /** + * Prepends the prefix to the start of the string if the string does not already start with any of the prefixes. + * + *
+     * StringUtils.prependIfMissing(null, null) = null
+     * StringUtils.prependIfMissing("abc", null) = "abc"
+     * StringUtils.prependIfMissing("", "xyz") = "xyz"
+     * StringUtils.prependIfMissing("abc", "xyz") = "xyzabc"
+     * StringUtils.prependIfMissing("xyzabc", "xyz") = "xyzabc"
+     * StringUtils.prependIfMissing("XYZabc", "xyz") = "xyzXYZabc"
+     * 
+ *

+ * With additional prefixes, + *

+ * + *
+     * StringUtils.prependIfMissing(null, null, null) = null
+     * StringUtils.prependIfMissing("abc", null, null) = "abc"
+     * StringUtils.prependIfMissing("", "xyz", null) = "xyz"
+     * StringUtils.prependIfMissing("abc", "xyz", new CharSequence[]{null}) = "xyzabc"
+     * StringUtils.prependIfMissing("abc", "xyz", "") = "abc"
+     * StringUtils.prependIfMissing("abc", "xyz", "mno") = "xyzabc"
+     * StringUtils.prependIfMissing("xyzabc", "xyz", "mno") = "xyzabc"
+     * StringUtils.prependIfMissing("mnoabc", "xyz", "mno") = "mnoabc"
+     * StringUtils.prependIfMissing("XYZabc", "xyz", "mno") = "xyzXYZabc"
+     * StringUtils.prependIfMissing("MNOabc", "xyz", "mno") = "xyzMNOabc"
+     * 
+ * + * @param str The string. + * @param prefix The prefix to prepend to the start of the string. + * @param prefixes Additional prefixes that are valid. + * @return A new String if prefix was prepended, the same string otherwise. + * @since 3.2 + * @deprecated Use {@link Strings#prependIfMissing(String, CharSequence, CharSequence...) Strings.CS.prependIfMissing(String, CharSequence, + * CharSequence...)}. + */ + @Deprecated + public static String prependIfMissing(final String str, final CharSequence prefix, final CharSequence... prefixes) { + return Strings.CS.prependIfMissing(str, prefix, prefixes); + } + + /** + * Prepends the prefix to the start of the string if the string does not already start, case-insensitive, with any of the prefixes. + * + *
+     * StringUtils.prependIfMissingIgnoreCase(null, null) = null
+     * StringUtils.prependIfMissingIgnoreCase("abc", null) = "abc"
+     * StringUtils.prependIfMissingIgnoreCase("", "xyz") = "xyz"
+     * StringUtils.prependIfMissingIgnoreCase("abc", "xyz") = "xyzabc"
+     * StringUtils.prependIfMissingIgnoreCase("xyzabc", "xyz") = "xyzabc"
+     * StringUtils.prependIfMissingIgnoreCase("XYZabc", "xyz") = "XYZabc"
+     * 
+ *

+ * With additional prefixes, + *

+ * + *
+     * StringUtils.prependIfMissingIgnoreCase(null, null, null) = null
+     * StringUtils.prependIfMissingIgnoreCase("abc", null, null) = "abc"
+     * StringUtils.prependIfMissingIgnoreCase("", "xyz", null) = "xyz"
+     * StringUtils.prependIfMissingIgnoreCase("abc", "xyz", new CharSequence[]{null}) = "xyzabc"
+     * StringUtils.prependIfMissingIgnoreCase("abc", "xyz", "") = "abc"
+     * StringUtils.prependIfMissingIgnoreCase("abc", "xyz", "mno") = "xyzabc"
+     * StringUtils.prependIfMissingIgnoreCase("xyzabc", "xyz", "mno") = "xyzabc"
+     * StringUtils.prependIfMissingIgnoreCase("mnoabc", "xyz", "mno") = "mnoabc"
+     * StringUtils.prependIfMissingIgnoreCase("XYZabc", "xyz", "mno") = "XYZabc"
+     * StringUtils.prependIfMissingIgnoreCase("MNOabc", "xyz", "mno") = "MNOabc"
+     * 
+ * + * @param str The string. + * @param prefix The prefix to prepend to the start of the string. + * @param prefixes Additional prefixes that are valid (optional). + * @return A new String if prefix was prepended, the same string otherwise. + * @since 3.2 + * @deprecated Use {@link Strings#prependIfMissing(String, CharSequence, CharSequence...) Strings.CI.prependIfMissing(String, CharSequence, + * CharSequence...)}. + */ + @Deprecated + public static String prependIfMissingIgnoreCase(final String str, final CharSequence prefix, final CharSequence... prefixes) { + return Strings.CI.prependIfMissing(str, prefix, prefixes); + } + + /** + * Removes all occurrences of a character from within the source string. + * + *

+ * A {@code null} source string will return {@code null}. An empty ("") source string will return the empty string. + *

+ * + *
+     * StringUtils.remove(null, *)       = null
+     * StringUtils.remove("", *)         = ""
+     * StringUtils.remove("queued", 'u') = "qeed"
+     * StringUtils.remove("queued", 'z') = "queued"
+     * 
+ * + * @param str the source String to search, may be null. + * @param remove the char to search for and remove, may be null. + * @return the substring with the char removed if found, {@code null} if null String input. + * @since 2.1 + */ + public static String remove(final String str, final char remove) { + if (isEmpty(str) || str.indexOf(remove) == INDEX_NOT_FOUND) { + return str; + } + final char[] chars = str.toCharArray(); + int pos = 0; + for (int i = 0; i < chars.length; i++) { + if (chars[i] != remove) { + chars[pos++] = chars[i]; + } + } + return new String(chars, 0, pos); + } + + /** + * Removes all occurrences of a substring from within the source string. + * + *

+ * A {@code null} source string will return {@code null}. An empty ("") source string will return the empty string. A {@code null} remove string will return + * the source string. An empty ("") remove string will return the source string. + *

+ * + *
+     * StringUtils.remove(null, *)        = null
+     * StringUtils.remove("", *)          = ""
+     * StringUtils.remove(*, null)        = *
+     * StringUtils.remove(*, "")          = *
+     * StringUtils.remove("queued", "ue") = "qd"
+     * StringUtils.remove("queued", "zz") = "queued"
+     * 
+ * + * @param str the source String to search, may be null. + * @param remove the String to search for and remove, may be null. + * @return the substring with the string removed if found, {@code null} if null String input. + * @since 2.1 + * @deprecated Use {@link Strings#remove(String, String) Strings.CS.remove(String, String)}. + */ + @Deprecated + public static String remove(final String str, final String remove) { + return Strings.CS.remove(str, remove); + } + + /** + * Removes each substring of the text String that matches the given regular expression. + * + * This method is a {@code null} safe equivalent to: + *
    + *
  • {@code text.replaceAll(regex, StringUtils.EMPTY)}
  • + *
  • {@code Pattern.compile(regex).matcher(text).replaceAll(StringUtils.EMPTY)}
  • + *
+ * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *

+ * Unlike in the {@link #removePattern(String, String)} method, the {@link Pattern#DOTALL} option is NOT automatically added. To use the DOTALL option + * prepend {@code "(?s)"} to the regex. DOTALL is also known as single-line mode in Perl. + *

+ * + *
{@code
+     * StringUtils.removeAll(null, *)      = null
+     * StringUtils.removeAll("any", (String) null)  = "any"
+     * StringUtils.removeAll("any", "")    = "any"
+     * StringUtils.removeAll("any", ".*")  = ""
+     * StringUtils.removeAll("any", ".+")  = ""
+     * StringUtils.removeAll("abc", ".?")  = ""
+     * StringUtils.removeAll("A<__>\n<__>B", "<.*>")      = "A\nB"
+     * StringUtils.removeAll("A<__>\n<__>B", "(?s)<.*>")  = "AB"
+     * StringUtils.removeAll("ABCabc123abc", "[a-z]")     = "ABC123"
+     * }
+ * + * @param text text to remove from, may be null. + * @param regex the regular expression to which this string is to be matched. + * @return the text with any removes processed, {@code null} if null String input. + * @throws java.util.regex.PatternSyntaxException if the regular expression's syntax is invalid. + * @see #replaceAll(String, String, String) + * @see #removePattern(String, String) + * @see String#replaceAll(String, String) + * @see java.util.regex.Pattern + * @see java.util.regex.Pattern#DOTALL + * @since 3.5 + * @deprecated Use {@link RegExUtils#removeAll(String, String)}. + */ + @Deprecated + public static String removeAll(final String text, final String regex) { + return RegExUtils.removeAll(text, regex); + } + + /** + * Removes a substring only if it is at the end of a source string, otherwise returns the source string. + * + *

+ * A {@code null} source string will return {@code null}. An empty ("") source string will return the empty string. A {@code null} search string will return + * the source string. + *

+ * + *
+     * StringUtils.removeEnd(null, *)      = null
+     * StringUtils.removeEnd("", *)        = ""
+     * StringUtils.removeEnd(*, null)      = *
+     * StringUtils.removeEnd("www.domain.com", ".com.")  = "www.domain.com"
+     * StringUtils.removeEnd("www.domain.com", ".com")   = "www.domain"
+     * StringUtils.removeEnd("www.domain.com", "domain") = "www.domain.com"
+     * StringUtils.removeEnd("abc", "")    = "abc"
+     * 
+ * + * @param str the source String to search, may be null. + * @param remove the String to search for and remove, may be null. + * @return the substring with the string removed if found, {@code null} if null String input. + * @since 2.1 + * @deprecated Use {@link Strings#removeEnd(String, CharSequence) Strings.CS.removeEnd(String, CharSequence)}. + */ + @Deprecated + public static String removeEnd(final String str, final String remove) { + return Strings.CS.removeEnd(str, remove); + } + + /** + * Case-insensitive removal of a substring if it is at the end of a source string, otherwise returns the source string. + * + *

+ * A {@code null} source string will return {@code null}. An empty ("") source string will return the empty string. A {@code null} search string will return + * the source string. + *

+ * + *
+     * StringUtils.removeEndIgnoreCase(null, *)      = null
+     * StringUtils.removeEndIgnoreCase("", *)        = ""
+     * StringUtils.removeEndIgnoreCase(*, null)      = *
+     * StringUtils.removeEndIgnoreCase("www.domain.com", ".com.")  = "www.domain.com"
+     * StringUtils.removeEndIgnoreCase("www.domain.com", ".com")   = "www.domain"
+     * StringUtils.removeEndIgnoreCase("www.domain.com", "domain") = "www.domain.com"
+     * StringUtils.removeEndIgnoreCase("abc", "")    = "abc"
+     * StringUtils.removeEndIgnoreCase("www.domain.com", ".COM") = "www.domain"
+     * StringUtils.removeEndIgnoreCase("www.domain.COM", ".com") = "www.domain"
+     * 
+ * + * @param str the source String to search, may be null. + * @param remove the String to search for (case-insensitive) and remove, may be null. + * @return the substring with the string removed if found, {@code null} if null String input. + * @since 2.4 + * @deprecated Use {@link Strings#removeEnd(String, CharSequence) Strings.CI.removeEnd(String, CharSequence)}. + */ + @Deprecated + public static String removeEndIgnoreCase(final String str, final String remove) { + return Strings.CI.removeEnd(str, remove); + } + + /** + * Removes the first substring of the text string that matches the given regular expression. + * + * This method is a {@code null} safe equivalent to: + *
    + *
  • {@code text.replaceFirst(regex, StringUtils.EMPTY)}
  • + *
  • {@code Pattern.compile(regex).matcher(text).replaceFirst(StringUtils.EMPTY)}
  • + *
+ * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *

+ * The {@link Pattern#DOTALL} option is NOT automatically added. To use the DOTALL option prepend {@code "(?s)"} to the regex. DOTALL is also known as + * single-line mode in Perl. + *

+ * + *
{@code
+     * StringUtils.removeFirst(null, *)      = null
+     * StringUtils.removeFirst("any", (String) null)  = "any"
+     * StringUtils.removeFirst("any", "")    = "any"
+     * StringUtils.removeFirst("any", ".*")  = ""
+     * StringUtils.removeFirst("any", ".+")  = ""
+     * StringUtils.removeFirst("abc", ".?")  = "bc"
+     * StringUtils.removeFirst("A<__>\n<__>B", "<.*>")      = "A\n<__>B"
+     * StringUtils.removeFirst("A<__>\n<__>B", "(?s)<.*>")  = "AB"
+     * StringUtils.removeFirst("ABCabc123", "[a-z]")          = "ABCbc123"
+     * StringUtils.removeFirst("ABCabc123abc", "[a-z]+")      = "ABC123abc"
+     * }
+ * + * @param text text to remove from, may be null. + * @param regex the regular expression to which this string is to be matched. + * @return the text with the first replacement processed, {@code null} if null String input. + * @throws java.util.regex.PatternSyntaxException if the regular expression's syntax is invalid. + * @see #replaceFirst(String, String, String) + * @see String#replaceFirst(String, String) + * @see java.util.regex.Pattern + * @see java.util.regex.Pattern#DOTALL + * @since 3.5 + * @deprecated Use {@link RegExUtils#replaceFirst(String, String, String) RegExUtils.replaceFirst(String, String, EMPTY)}. + */ + @Deprecated + public static String removeFirst(final String text, final String regex) { + return replaceFirst(text, regex, EMPTY); + } + + /** + * Case-insensitive removal of all occurrences of a substring from within the source string. + * + *

+ * A {@code null} source string will return {@code null}. An empty ("") source string will return the empty string. A {@code null} remove string will return + * the source string. An empty ("") remove string will return the source string. + *

+ * + *
+     * StringUtils.removeIgnoreCase(null, *)        = null
+     * StringUtils.removeIgnoreCase("", *)          = ""
+     * StringUtils.removeIgnoreCase(*, null)        = *
+     * StringUtils.removeIgnoreCase(*, "")          = *
+     * StringUtils.removeIgnoreCase("queued", "ue") = "qd"
+     * StringUtils.removeIgnoreCase("queued", "zz") = "queued"
+     * StringUtils.removeIgnoreCase("quEUed", "UE") = "qd"
+     * StringUtils.removeIgnoreCase("queued", "zZ") = "queued"
+     * 
+ * + * @param str the source String to search, may be null. + * @param remove the String to search for (case-insensitive) and remove, may be null. + * @return the substring with the string removed if found, {@code null} if null String input. + * @since 3.5 + * @deprecated Use {@link Strings#remove(String, String) Strings.CI.remove(String, String)}. + */ + @Deprecated + public static String removeIgnoreCase(final String str, final String remove) { + return Strings.CI.remove(str, remove); + } + + /** + * Removes each substring of the source String that matches the given regular expression using the DOTALL option. + * + * This call is a {@code null} safe equivalent to: + *
    + *
  • {@code source.replaceAll("(?s)" + regex, StringUtils.EMPTY)}
  • + *
  • {@code Pattern.compile(regex, Pattern.DOTALL).matcher(source).replaceAll(StringUtils.EMPTY)}
  • + *
+ * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *
{@code
+     * StringUtils.removePattern(null, *)       = null
+     * StringUtils.removePattern("any", (String) null)   = "any"
+     * StringUtils.removePattern("A<__>\n<__>B", "<.*>")  = "AB"
+     * StringUtils.removePattern("ABCabc123", "[a-z]")    = "ABC123"
+     * }
+ * + * @param source the source string. + * @param regex the regular expression to which this string is to be matched. + * @return The resulting {@link String}. + * @see #replacePattern(String, String, String) + * @see String#replaceAll(String, String) + * @see Pattern#DOTALL + * @since 3.2 + * @since 3.5 Changed {@code null} reference passed to this method is a no-op. + * @deprecated Use {@link RegExUtils#removePattern(CharSequence, String)}. + */ + @Deprecated + public static String removePattern(final String source, final String regex) { + return RegExUtils.removePattern(source, regex); + } + + /** + * Removes a char only if it is at the beginning of a source string, otherwise returns the source string. + * + *

+ * A {@code null} source string will return {@code null}. An empty ("") source string will return the empty string. A {@code null} search char will return + * the source string. + *

+ * + *
+     * StringUtils.removeStart(null, *)      = null
+     * StringUtils.removeStart("", *)        = ""
+     * StringUtils.removeStart(*, null)      = *
+     * StringUtils.removeStart("/path", '/') = "path"
+     * StringUtils.removeStart("path", '/')  = "path"
+     * StringUtils.removeStart("path", 0)    = "path"
+     * 
+ * + * @param str the source String to search, may be null. + * @param remove the char to search for and remove. + * @return the substring with the char removed if found, {@code null} if null String input. + * @since 3.13.0 + */ + public static String removeStart(final String str, final char remove) { + if (isEmpty(str)) { + return str; + } + return str.charAt(0) == remove ? str.substring(1) : str; + } + + /** + * Removes a substring only if it is at the beginning of a source string, otherwise returns the source string. + * + *

+ * A {@code null} source string will return {@code null}. An empty ("") source string will return the empty string. A {@code null} search string will return + * the source string. + *

+ * + *
+     * StringUtils.removeStart(null, *)                    = null
+     * StringUtils.removeStart("", *)                      = ""
+     * StringUtils.removeStart(*, null)                    = *
+     * StringUtils.removeStart("www.domain.com", "www.")   = "domain.com"
+     * StringUtils.removeStart("domain.com", "www.")       = "domain.com"
+     * StringUtils.removeStart("www.domain.com", "domain") = "www.domain.com"
+     * StringUtils.removeStart("abc", "")                  = "abc"
+     * 
+ * + * @param str the source String to search, may be null. + * @param remove the String to search for and remove, may be null. + * @return the substring with the string removed if found, {@code null} if null String input. + * @since 2.1 + * @deprecated Use {@link Strings#removeStart(String, CharSequence) Strings.CS.removeStart(String, CharSequence)}. + */ + @Deprecated + public static String removeStart(final String str, final String remove) { + return Strings.CS.removeStart(str, remove); + } + + /** + * Case-insensitive removal of a substring if it is at the beginning of a source string, otherwise returns the source string. + * + *

+ * A {@code null} source string will return {@code null}. An empty ("") source string will return the empty string. A {@code null} search string will return + * the source string. + *

+ * + *
+     * StringUtils.removeStartIgnoreCase(null, *)                    = null
+     * StringUtils.removeStartIgnoreCase("", *)                      = ""
+     * StringUtils.removeStartIgnoreCase(*, null)                    = *
+     * StringUtils.removeStartIgnoreCase("www.domain.com", "www.")   = "domain.com"
+     * StringUtils.removeStartIgnoreCase("www.domain.com", "WWW.")   = "domain.com"
+     * StringUtils.removeStartIgnoreCase("domain.com", "www.")       = "domain.com"
+     * StringUtils.removeStartIgnoreCase("www.domain.com", "domain") = "www.domain.com"
+     * StringUtils.removeStartIgnoreCase("abc", "")                  = "abc"
+     * 
+ * + * @param str the source String to search, may be null. + * @param remove the String to search for (case-insensitive) and remove, may be null. + * @return the substring with the string removed if found, {@code null} if null String input. + * @since 2.4 + * @deprecated Use {@link Strings#removeStart(String, CharSequence) Strings.CI.removeStart(String, CharSequence)}. + */ + @Deprecated + public static String removeStartIgnoreCase(final String str, final String remove) { + return Strings.CI.removeStart(str, remove); + } + + /** + * Returns padding using the specified delimiter repeated to a given length. + * + *
+     * StringUtils.repeat('e', 0)  = ""
+     * StringUtils.repeat('e', 3)  = "eee"
+     * StringUtils.repeat('e', -2) = ""
+     * 
+ * + *

+ * Note: this method does not support padding with Unicode Supplementary Characters + * as they require a pair of {@code char}s to be represented. If you are needing to support full I18N of your applications consider using + * {@link #repeat(String, int)} instead. + *

+ * + * @param repeat character to repeat. + * @param count number of times to repeat char, negative treated as zero. + * @return String with repeated character. + * @see #repeat(String, int) + */ + public static String repeat(final char repeat, final int count) { + if (count <= 0) { + return EMPTY; + } + return new String(ArrayFill.fill(new char[count], repeat)); + } + + /** + * Repeats a String {@code repeat} times to form a new String. + * + *
+     * StringUtils.repeat(null, 2) = null
+     * StringUtils.repeat("", 0)   = ""
+     * StringUtils.repeat("", 2)   = ""
+     * StringUtils.repeat("a", 3)  = "aaa"
+     * StringUtils.repeat("ab", 2) = "abab"
+     * StringUtils.repeat("a", -2) = ""
+     * 
+ * + * @param repeat the String to repeat, may be null. + * @param count number of times to repeat str, negative treated as zero. + * @return a new String consisting of the original String repeated, {@code null} if null String input. + */ + public static String repeat(final String repeat, final int count) { + // Performance tuned for 2.0 (JDK1.4) + if (repeat == null) { + return null; + } + if (count <= 0) { + return EMPTY; + } + final int inputLength = repeat.length(); + if (count == 1 || inputLength == 0) { + return repeat; + } + if (inputLength == 1 && count <= PAD_LIMIT) { + return repeat(repeat.charAt(0), count); + } + final int outputLength = inputLength * count; + switch (inputLength) { + case 1: + return repeat(repeat.charAt(0), count); + case 2: + final char ch0 = repeat.charAt(0); + final char ch1 = repeat.charAt(1); + final char[] output2 = new char[outputLength]; + for (int i = count * 2 - 2; i >= 0; i--, i--) { + output2[i] = ch0; + output2[i + 1] = ch1; + } + return new String(output2); + default: + final StringBuilder buf = new StringBuilder(outputLength); + for (int i = 0; i < count; i++) { + buf.append(repeat); + } + return buf.toString(); + } + } + + /** + * Repeats a String {@code repeat} times to form a new String, with a String separator injected each time. + * + *
+     * StringUtils.repeat(null, null, 2) = null
+     * StringUtils.repeat(null, "x", 2)  = null
+     * StringUtils.repeat("", null, 0)   = ""
+     * StringUtils.repeat("", "", 2)     = ""
+     * StringUtils.repeat("", "x", 3)    = "xx"
+     * StringUtils.repeat("?", ", ", 3)  = "?, ?, ?"
+     * 
+ * + * @param repeat the String to repeat, may be null. + * @param separator the String to inject, may be null. + * @param count number of times to repeat str, negative treated as zero. + * @return a new String consisting of the original String repeated, {@code null} if null String input. + * @since 2.5 + */ + public static String repeat(final String repeat, final String separator, final int count) { + if (repeat == null || separator == null) { + return repeat(repeat, count); + } + // given that repeat(String, int) is quite optimized, better to rely on it than try and splice this into it + final String result = repeat(repeat + separator, count); + return Strings.CS.removeEnd(result, separator); + } + + /** + * Replaces all occurrences of a String within another String. + * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *
+     * StringUtils.replace(null, *, *)        = null
+     * StringUtils.replace("", *, *)          = ""
+     * StringUtils.replace("any", null, *)    = "any"
+     * StringUtils.replace("any", *, null)    = "any"
+     * StringUtils.replace("any", "", *)      = "any"
+     * StringUtils.replace("aba", "a", null)  = "aba"
+     * StringUtils.replace("aba", "a", "")    = "b"
+     * StringUtils.replace("aba", "a", "z")   = "zbz"
+     * 
+ * + * @param text text to search and replace in, may be null. + * @param searchString the String to search for, may be null. + * @param replacement the String to replace it with, may be null. + * @return the text with any replacements processed, {@code null} if null String input. + * @see #replace(String text, String searchString, String replacement, int max) + * @deprecated Use {@link Strings#replace(String, String, String) Strings.CS.replace(String, String, String)}. + */ + @Deprecated + public static String replace(final String text, final String searchString, final String replacement) { + return Strings.CS.replace(text, searchString, replacement); + } + + /** + * Replaces a String with another String inside a larger String, for the first {@code max} values of the search String. + * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *
+     * StringUtils.replace(null, *, *, *)         = null
+     * StringUtils.replace("", *, *, *)           = ""
+     * StringUtils.replace("any", null, *, *)     = "any"
+     * StringUtils.replace("any", *, null, *)     = "any"
+     * StringUtils.replace("any", "", *, *)       = "any"
+     * StringUtils.replace("any", *, *, 0)        = "any"
+     * StringUtils.replace("abaa", "a", null, -1) = "abaa"
+     * StringUtils.replace("abaa", "a", "", -1)   = "b"
+     * StringUtils.replace("abaa", "a", "z", 0)   = "abaa"
+     * StringUtils.replace("abaa", "a", "z", 1)   = "zbaa"
+     * StringUtils.replace("abaa", "a", "z", 2)   = "zbza"
+     * StringUtils.replace("abaa", "a", "z", -1)  = "zbzz"
+     * 
+ * + * @param text text to search and replace in, may be null. + * @param searchString the String to search for, may be null. + * @param replacement the String to replace it with, may be null. + * @param max maximum number of values to replace, or {@code -1} if no maximum. + * @return the text with any replacements processed, {@code null} if null String input. + * @deprecated Use {@link Strings#replace(String, String, String, int) Strings.CS.replace(String, String, String, int)}. + */ + @Deprecated + public static String replace(final String text, final String searchString, final String replacement, final int max) { + return Strings.CS.replace(text, searchString, replacement, max); + } + + /** + * Replaces each substring of the text String that matches the given regular expression with the given replacement. + * + * This method is a {@code null} safe equivalent to: + *
    + *
  • {@code text.replaceAll(regex, replacement)}
  • + *
  • {@code Pattern.compile(regex).matcher(text).replaceAll(replacement)}
  • + *
+ * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *

+ * Unlike in the {@link #replacePattern(String, String, String)} method, the {@link Pattern#DOTALL} option is NOT automatically added. To use the DOTALL + * option prepend {@code "(?s)"} to the regex. DOTALL is also known as single-line mode in Perl. + *

+ * + *
{@code
+     * StringUtils.replaceAll(null, *, *)                                         = null
+     * StringUtils.replaceAll("any", (String) null, *)                            = "any"
+     * StringUtils.replaceAll("any", *, null)                                     = "any"
+     * StringUtils.replaceAll("", "", "zzz")                                      = "zzz"
+     * StringUtils.replaceAll("", ".*", "zzz")                                    = "zzz"
+     * StringUtils.replaceAll("", ".+", "zzz")                                    = ""
+     * StringUtils.replaceAll("abc", "", "ZZ")                                    = "ZZaZZbZZcZZ"
+     * StringUtils.replaceAll("<__>\n<__>", "<.*>", "z")                          = "z\nz"
+     * StringUtils.replaceAll("<__>\n<__>", "(?s)<.*>", "z")                      = "z"
+     * StringUtils.replaceAll("ABCabc123", "[a-z]", "_")                          = "ABC___123"
+     * StringUtils.replaceAll("ABCabc123", "[^A-Z0-9]+", "_")                     = "ABC_123"
+     * StringUtils.replaceAll("ABCabc123", "[^A-Z0-9]+", "")                      = "ABC123"
+     * StringUtils.replaceAll("Lorem ipsum  dolor   sit", "( +)([a-z]+)", "_$2")  = "Lorem_ipsum_dolor_sit"
+     * }
+ * + * @param text text to search and replace in, may be null. + * @param regex the regular expression to which this string is to be matched. + * @param replacement the string to be substituted for each match. + * @return the text with any replacements processed, {@code null} if null String input. + * @throws java.util.regex.PatternSyntaxException if the regular expression's syntax is invalid. + * @see #replacePattern(String, String, String) + * @see String#replaceAll(String, String) + * @see java.util.regex.Pattern + * @see java.util.regex.Pattern#DOTALL + * @since 3.5 + * @deprecated Use {@link RegExUtils#replaceAll(String, String, String)}. + */ + @Deprecated + public static String replaceAll(final String text, final String regex, final String replacement) { + return RegExUtils.replaceAll(text, regex, replacement); + } + + /** + * Replaces all occurrences of a character in a String with another. This is a null-safe version of {@link String#replace(char, char)}. + * + *

+ * A {@code null} string input returns {@code null}. An empty ("") string input returns an empty string. + *

+ * + *
+     * StringUtils.replaceChars(null, *, *)        = null
+     * StringUtils.replaceChars("", *, *)          = ""
+     * StringUtils.replaceChars("abcba", 'b', 'y') = "aycya"
+     * StringUtils.replaceChars("abcba", 'z', 'y') = "abcba"
+     * 
+ * + * @param str String to replace characters in, may be null. + * @param searchChar the character to search for, may be null. + * @param replaceChar the character to replace, may be null. + * @return modified String, {@code null} if null string input. + * @since 2.0 + */ + public static String replaceChars(final String str, final char searchChar, final char replaceChar) { + if (str == null) { + return null; + } + return str.replace(searchChar, replaceChar); + } + + /** + * Replaces multiple characters in a String in one go. This method can also be used to delete characters. + * + *

+ * For example: + *

+ *
+     * replaceChars("hello", "ho", "jy") = jelly.
+     * 
+ * + *

+ * A {@code null} string input returns {@code null}. An empty ("") string input returns an empty string. A null or empty set of search characters returns + * the input string. + *

+ * + *

+ * The length of the search characters should normally equal the length of the replace characters. If the search characters is longer, then the extra search + * characters are deleted. If the search characters is shorter, then the extra replace characters are ignored. + *

+ * + *
+     * StringUtils.replaceChars(null, *, *)           = null
+     * StringUtils.replaceChars("", *, *)             = ""
+     * StringUtils.replaceChars("abc", null, *)       = "abc"
+     * StringUtils.replaceChars("abc", "", *)         = "abc"
+     * StringUtils.replaceChars("abc", "b", null)     = "ac"
+     * StringUtils.replaceChars("abc", "b", "")       = "ac"
+     * StringUtils.replaceChars("abcba", "bc", "yz")  = "ayzya"
+     * StringUtils.replaceChars("abcba", "bc", "y")   = "ayya"
+     * StringUtils.replaceChars("abcba", "bc", "yzx") = "ayzya"
+     * 
+ * + * @param str String to replace characters in, may be null. + * @param searchChars a set of characters to search for, may be null. + * @param replaceChars a set of characters to replace, may be null. + * @return modified String, {@code null} if null string input. + * @since 2.0 + */ + public static String replaceChars(final String str, final String searchChars, String replaceChars) { + if (isEmpty(str) || isEmpty(searchChars)) { + return str; + } + replaceChars = ObjectUtils.toString(replaceChars); + boolean modified = false; + final int replaceCharsLength = replaceChars.length(); + final int strLength = str.length(); + final StringBuilder buf = new StringBuilder(strLength); + for (int i = 0; i < strLength; i++) { + final char ch = str.charAt(i); + final int index = searchChars.indexOf(ch); + if (index >= 0) { + modified = true; + if (index < replaceCharsLength) { + buf.append(replaceChars.charAt(index)); + } + } else { + buf.append(ch); + } + } + if (modified) { + return buf.toString(); + } + return str; + } + + /** + * Replaces all occurrences of Strings within another String. + * + *

+ * A {@code null} reference passed to this method is a no-op, or if any "search string" or "string to replace" is null, that replace will be ignored. This + * will not repeat. For repeating replaces, call the overloaded method. + *

+ * + *
+     *  StringUtils.replaceEach(null, *, *)                                                = null
+     *  StringUtils.replaceEach("", *, *)                                                  = ""
+     *  StringUtils.replaceEach("aba", null, null)                                         = "aba"
+     *  StringUtils.replaceEach("aba", new String[0], null)                                = "aba"
+     *  StringUtils.replaceEach("aba", null, new String[0])                                = "aba"
+     *  StringUtils.replaceEach("aba", new String[]{"a"}, null)                            = "aba"
+     *  StringUtils.replaceEach("aba", new String[]{"a"}, new String[]{""})                = "b"
+     *  StringUtils.replaceEach("aba", new String[]{null}, new String[]{"a"})              = "aba"
+     *  StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"w", "t"})  = "wcte"
+     *  (example of how it does not repeat)
+     *  StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"})  = "dcte"
+     * 
+ * + * @param text text to search and replace in, no-op if null. + * @param searchList the Strings to search for, no-op if null. + * @param replacementList the Strings to replace them with, no-op if null. + * @return the text with any replacements processed, {@code null} if null String input. + * @throws IllegalArgumentException if the lengths of the arrays are not the same (null is ok, and/or size 0). + * @since 2.4 + */ + public static String replaceEach(final String text, final String[] searchList, final String[] replacementList) { + return replaceEach(text, searchList, replacementList, false, 0); + } + + /** + * Replace all occurrences of Strings within another String. This is a private recursive helper method for + * {@link #replaceEachRepeatedly(String, String[], String[])} and {@link #replaceEach(String, String[], String[])} + * + *

+ * A {@code null} reference passed to this method is a no-op, or if any "search string" or "string to replace" is null, that replace will be ignored. + *

+ * + *
+     *  StringUtils.replaceEach(null, *, *, *, *)                                                     = null
+     *  StringUtils.replaceEach("", *, *, *, *)                                                       = ""
+     *  StringUtils.replaceEach("aba", null, null, *, *)                                              = "aba"
+     *  StringUtils.replaceEach("aba", new String[0], null, *, *)                                     = "aba"
+     *  StringUtils.replaceEach("aba", null, new String[0], *, *)                                     = "aba"
+     *  StringUtils.replaceEach("aba", new String[]{"a"}, null, *, *)                                 = "aba"
+     *  StringUtils.replaceEach("aba", new String[]{"a"}, new String[]{""}, *, >=0)                   = "b"
+     *  StringUtils.replaceEach("aba", new String[]{null}, new String[]{"a"}, *, >=0)                 = "aba"
+     *  StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"w", "t"}, *, >=0)     = "wcte"
+     *  (example of how it repeats)
+     *  StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"}, false, >=0) = "dcte"
+     *  StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"}, true, >=2)  = "tcte"
+     *  StringUtils.replaceEach("abcde", new String[]{"ab", "d"}, new String[]{"d", "ab"}, *, *)      = Throws {@link IllegalStateException}
+     * 
+ * + * @param text text to search and replace in, no-op if null. + * @param searchList the Strings to search for, no-op if null. + * @param replacementList the Strings to replace them with, no-op if null. + * @param repeat if true, then replace repeatedly until there are no more possible replacements or timeToLive < 0. + * @param timeToLive if less than 0 then there is a circular reference and endless loop. + * @return the text with any replacements processed, {@code null} if null String input. + * @throws IllegalStateException if the search is repeating and there is an endless loop due to outputs of one being inputs to another. + * @throws IllegalArgumentException if the lengths of the arrays are not the same (null is ok, and/or size 0). + * @since 2.4 + */ + private static String replaceEach( + final String text, final String[] searchList, final String[] replacementList, final boolean repeat, final int timeToLive) { + + // Performance note: This creates very few new objects (one major goal) + // let me know if there are performance requests, we can create a harness to measure + if (isEmpty(text) || ArrayUtils.isEmpty(searchList) || ArrayUtils.isEmpty(replacementList)) { + return text; + } + + // if recursing, this shouldn't be less than 0 + if (timeToLive < 0) { + throw new IllegalStateException("Aborting to protect against StackOverflowError - " + + "output of one loop is the input of another"); + } + + final int searchLength = searchList.length; + final int replacementLength = replacementList.length; + + // make sure lengths are ok, these need to be equal + if (searchLength != replacementLength) { + throw new IllegalArgumentException("Search and Replace array lengths don't match: " + + searchLength + + " vs " + + replacementLength); + } + + // keep track of which still have matches + final boolean[] noMoreMatchesForReplIndex = new boolean[searchLength]; + + // index on index that the match was found + int textIndex = -1; + int replaceIndex = -1; + int tempIndex; + + // index of replace array that will replace the search string found + // NOTE: logic duplicated below START + for (int i = 0; i < searchLength; i++) { + if (noMoreMatchesForReplIndex[i] || isEmpty(searchList[i]) || replacementList[i] == null) { + continue; + } + tempIndex = text.indexOf(searchList[i]); + + // see if we need to keep searching for this + if (tempIndex == -1) { + noMoreMatchesForReplIndex[i] = true; + } else if (textIndex == -1 || tempIndex < textIndex) { + textIndex = tempIndex; + replaceIndex = i; + } + } + // NOTE: logic mostly below END + + // no search strings found, we are done + if (textIndex == -1) { + return text; + } + + int start = 0; + + // get a good guess on the size of the result buffer so it doesn't have to double if it goes over a bit + int increase = 0; + + // count the replacement text elements that are larger than their corresponding text being replaced + for (int i = 0; i < searchList.length; i++) { + if (searchList[i] == null || replacementList[i] == null) { + continue; + } + final int greater = replacementList[i].length() - searchList[i].length(); + if (greater > 0) { + increase += 3 * greater; // assume 3 matches + } + } + // have upper-bound at 20% increase, then let Java take over + increase = Math.min(increase, text.length() / 5); + + final StringBuilder buf = new StringBuilder(text.length() + increase); + + while (textIndex != -1) { + + for (int i = start; i < textIndex; i++) { + buf.append(text.charAt(i)); + } + buf.append(replacementList[replaceIndex]); + + start = textIndex + searchList[replaceIndex].length(); + + textIndex = -1; + replaceIndex = -1; + // find the next earliest match + // NOTE: logic mostly duplicated above START + for (int i = 0; i < searchLength; i++) { + if (noMoreMatchesForReplIndex[i] || isEmpty(searchList[i]) || replacementList[i] == null) { + continue; + } + tempIndex = text.indexOf(searchList[i], start); + + // see if we need to keep searching for this + if (tempIndex == -1) { + noMoreMatchesForReplIndex[i] = true; + } else if (textIndex == -1 || tempIndex < textIndex) { + textIndex = tempIndex; + replaceIndex = i; + } + } + // NOTE: logic duplicated above END + + } + final int textLength = text.length(); + for (int i = start; i < textLength; i++) { + buf.append(text.charAt(i)); + } + final String result = buf.toString(); + if (!repeat) { + return result; + } + + return replaceEach(result, searchList, replacementList, repeat, timeToLive - 1); + } + + /** + * Replaces all occurrences of Strings within another String. + * + *

+ * A {@code null} reference passed to this method is a no-op, or if any "search string" or "string to replace" is null, that replace will be ignored. + *

+ * + *
+     *  StringUtils.replaceEachRepeatedly(null, *, *)                                                = null
+     *  StringUtils.replaceEachRepeatedly("", *, *)                                                  = ""
+     *  StringUtils.replaceEachRepeatedly("aba", null, null)                                         = "aba"
+     *  StringUtils.replaceEachRepeatedly("aba", new String[0], null)                                = "aba"
+     *  StringUtils.replaceEachRepeatedly("aba", null, new String[0])                                = "aba"
+     *  StringUtils.replaceEachRepeatedly("aba", new String[]{"a"}, null)                            = "aba"
+     *  StringUtils.replaceEachRepeatedly("aba", new String[]{"a"}, new String[]{""})                = "b"
+     *  StringUtils.replaceEachRepeatedly("aba", new String[]{null}, new String[]{"a"})              = "aba"
+     *  StringUtils.replaceEachRepeatedly("abcde", new String[]{"ab", "d"}, new String[]{"w", "t"})  = "wcte"
+     *  (example of how it repeats)
+     *  StringUtils.replaceEachRepeatedly("abcde", new String[]{"ab", "d"}, new String[]{"d", "t"})  = "tcte"
+     *  StringUtils.replaceEachRepeatedly("abcde", new String[]{"ab", "d"}, new String[]{"d", "ab"}) = Throws {@link IllegalStateException}
+     * 
+ * + * @param text text to search and replace in, no-op if null. + * @param searchList the Strings to search for, no-op if null. + * @param replacementList the Strings to replace them with, no-op if null. + * @return the text with any replacements processed, {@code null} if null String input. + * @throws IllegalStateException if the search is repeating and there is an endless loop due to outputs of one being inputs to another. + * @throws IllegalArgumentException if the lengths of the arrays are not the same (null is ok, and/or size 0). + * @since 2.4 + */ + public static String replaceEachRepeatedly(final String text, final String[] searchList, final String[] replacementList) { + final int timeToLive = Math.max(ArrayUtils.getLength(searchList), DEFAULT_TTL); + return replaceEach(text, searchList, replacementList, true, timeToLive); + } + + /** + * Replaces the first substring of the text string that matches the given regular expression with the given replacement. + * + * This method is a {@code null} safe equivalent to: + *
    + *
  • {@code text.replaceFirst(regex, replacement)}
  • + *
  • {@code Pattern.compile(regex).matcher(text).replaceFirst(replacement)}
  • + *
+ * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *

+ * The {@link Pattern#DOTALL} option is NOT automatically added. To use the DOTALL option prepend {@code "(?s)"} to the regex. DOTALL is also known as + * single-line mode in Perl. + *

+ * + *
{@code
+     * StringUtils.replaceFirst(null, *, *)       = null
+     * StringUtils.replaceFirst("any", (String) null, *)   = "any"
+     * StringUtils.replaceFirst("any", *, null)   = "any"
+     * StringUtils.replaceFirst("", "", "zzz")    = "zzz"
+     * StringUtils.replaceFirst("", ".*", "zzz")  = "zzz"
+     * StringUtils.replaceFirst("", ".+", "zzz")  = ""
+     * StringUtils.replaceFirst("abc", "", "ZZ")  = "ZZabc"
+     * StringUtils.replaceFirst("<__>\n<__>", "<.*>", "z")      = "z\n<__>"
+     * StringUtils.replaceFirst("<__>\n<__>", "(?s)<.*>", "z")  = "z"
+     * StringUtils.replaceFirst("ABCabc123", "[a-z]", "_")          = "ABC_bc123"
+     * StringUtils.replaceFirst("ABCabc123abc", "[^A-Z0-9]+", "_")  = "ABC_123abc"
+     * StringUtils.replaceFirst("ABCabc123abc", "[^A-Z0-9]+", "")   = "ABC123abc"
+     * StringUtils.replaceFirst("Lorem ipsum  dolor   sit", "( +)([a-z]+)", "_$2")  = "Lorem_ipsum  dolor   sit"
+     * }
+ * + * @param text text to search and replace in, may be null. + * @param regex the regular expression to which this string is to be matched. + * @param replacement the string to be substituted for the first match. + * @return the text with the first replacement processed, {@code null} if null String input. + * @throws java.util.regex.PatternSyntaxException if the regular expression's syntax is invalid. + * @see String#replaceFirst(String, String) + * @see java.util.regex.Pattern + * @see java.util.regex.Pattern#DOTALL + * @since 3.5 + * @deprecated Use {@link RegExUtils#replaceFirst(String, String, String)}. + */ + @Deprecated + public static String replaceFirst(final String text, final String regex, final String replacement) { + return RegExUtils.replaceFirst(text, regex, replacement); + } + + /** + * Case insensitively replaces all occurrences of a String within another String. + * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *
+     * StringUtils.replaceIgnoreCase(null, *, *)        = null
+     * StringUtils.replaceIgnoreCase("", *, *)          = ""
+     * StringUtils.replaceIgnoreCase("any", null, *)    = "any"
+     * StringUtils.replaceIgnoreCase("any", *, null)    = "any"
+     * StringUtils.replaceIgnoreCase("any", "", *)      = "any"
+     * StringUtils.replaceIgnoreCase("aba", "a", null)  = "aba"
+     * StringUtils.replaceIgnoreCase("abA", "A", "")    = "b"
+     * StringUtils.replaceIgnoreCase("aba", "A", "z")   = "zbz"
+     * 
+ * + * @param text text to search and replace in, may be null. + * @param searchString the String to search for (case-insensitive), may be null. + * @param replacement the String to replace it with, may be null. + * @return the text with any replacements processed, {@code null} if null String input. + * @see #replaceIgnoreCase(String text, String searchString, String replacement, int max) + * @since 3.5 + * @deprecated Use {@link Strings#replace(String, String, String) Strings.CI.replace(String, String, String)}. + */ + @Deprecated + public static String replaceIgnoreCase(final String text, final String searchString, final String replacement) { + return Strings.CI.replace(text, searchString, replacement); + } + + /** + * Case insensitively replaces a String with another String inside a larger String, for the first {@code max} values of the search String. + * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *
+     * StringUtils.replaceIgnoreCase(null, *, *, *)         = null
+     * StringUtils.replaceIgnoreCase("", *, *, *)           = ""
+     * StringUtils.replaceIgnoreCase("any", null, *, *)     = "any"
+     * StringUtils.replaceIgnoreCase("any", *, null, *)     = "any"
+     * StringUtils.replaceIgnoreCase("any", "", *, *)       = "any"
+     * StringUtils.replaceIgnoreCase("any", *, *, 0)        = "any"
+     * StringUtils.replaceIgnoreCase("abaa", "a", null, -1) = "abaa"
+     * StringUtils.replaceIgnoreCase("abaa", "a", "", -1)   = "b"
+     * StringUtils.replaceIgnoreCase("abaa", "a", "z", 0)   = "abaa"
+     * StringUtils.replaceIgnoreCase("abaa", "A", "z", 1)   = "zbaa"
+     * StringUtils.replaceIgnoreCase("abAa", "a", "z", 2)   = "zbza"
+     * StringUtils.replaceIgnoreCase("abAa", "a", "z", -1)  = "zbzz"
+     * 
+ * + * @param text text to search and replace in, may be null. + * @param searchString the String to search for (case-insensitive), may be null. + * @param replacement the String to replace it with, may be null. + * @param max maximum number of values to replace, or {@code -1} if no maximum. + * @return the text with any replacements processed, {@code null} if null String input. + * @since 3.5 + * @deprecated Use {@link Strings#replace(String, String, String, int) Strings.CI.replace(String, String, String, int)}. + */ + @Deprecated + public static String replaceIgnoreCase(final String text, final String searchString, final String replacement, final int max) { + return Strings.CI.replace(text, searchString, replacement, max); + } + + /** + * Replaces a String with another String inside a larger String, once. + * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *
+     * StringUtils.replaceOnce(null, *, *)        = null
+     * StringUtils.replaceOnce("", *, *)          = ""
+     * StringUtils.replaceOnce("any", null, *)    = "any"
+     * StringUtils.replaceOnce("any", *, null)    = "any"
+     * StringUtils.replaceOnce("any", "", *)      = "any"
+     * StringUtils.replaceOnce("aba", "a", null)  = "aba"
+     * StringUtils.replaceOnce("aba", "a", "")    = "ba"
+     * StringUtils.replaceOnce("aba", "a", "z")   = "zba"
+     * 
+ * + * @param text text to search and replace in, may be null. + * @param searchString the String to search for, may be null. + * @param replacement the String to replace with, may be null. + * @return the text with any replacements processed, {@code null} if null String input. + * @see #replace(String text, String searchString, String replacement, int max) + * @deprecated Use {@link Strings#replaceOnce(String, String, String) Strings.CS.replaceOnce(String, String, String)}. + */ + @Deprecated + public static String replaceOnce(final String text, final String searchString, final String replacement) { + return Strings.CS.replaceOnce(text, searchString, replacement); + } + + /** + * Case insensitively replaces a String with another String inside a larger String, once. + * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *
+     * StringUtils.replaceOnceIgnoreCase(null, *, *)        = null
+     * StringUtils.replaceOnceIgnoreCase("", *, *)          = ""
+     * StringUtils.replaceOnceIgnoreCase("any", null, *)    = "any"
+     * StringUtils.replaceOnceIgnoreCase("any", *, null)    = "any"
+     * StringUtils.replaceOnceIgnoreCase("any", "", *)      = "any"
+     * StringUtils.replaceOnceIgnoreCase("aba", "a", null)  = "aba"
+     * StringUtils.replaceOnceIgnoreCase("aba", "a", "")    = "ba"
+     * StringUtils.replaceOnceIgnoreCase("aba", "a", "z")   = "zba"
+     * StringUtils.replaceOnceIgnoreCase("FoOFoofoo", "foo", "") = "Foofoo"
+     * 
+ * + * @param text text to search and replace in, may be null. + * @param searchString the String to search for (case-insensitive), may be null. + * @param replacement the String to replace with, may be null. + * @return the text with any replacements processed, {@code null} if null String input. + * @see #replaceIgnoreCase(String text, String searchString, String replacement, int max) + * @since 3.5 + * @deprecated Use {@link Strings#replaceOnce(String, String, String) Strings.CI.replaceOnce(String, String, String)}. + */ + @Deprecated + public static String replaceOnceIgnoreCase(final String text, final String searchString, final String replacement) { + return Strings.CI.replaceOnce(text, searchString, replacement); + } + + /** + * Replaces each substring of the source String that matches the given regular expression with the given replacement using the {@link Pattern#DOTALL} + * option. DOTALL is also known as single-line mode in Perl. + * + * This call is a {@code null} safe equivalent to: + *
    + *
  • {@code source.replaceAll("(?s)" + regex, replacement)}
  • + *
  • {@code Pattern.compile(regex, Pattern.DOTALL).matcher(source).replaceAll(replacement)}
  • + *
+ * + *

+ * A {@code null} reference passed to this method is a no-op. + *

+ * + *
{@code
+     * StringUtils.replacePattern(null, *, *)                                         = null
+     * StringUtils.replacePattern("any", (String) null, *)                            = "any"
+     * StringUtils.replacePattern("any", *, null)                                     = "any"
+     * StringUtils.replacePattern("", "", "zzz")                                      = "zzz"
+     * StringUtils.replacePattern("", ".*", "zzz")                                    = "zzz"
+     * StringUtils.replacePattern("", ".+", "zzz")                                    = ""
+     * StringUtils.replacePattern("<__>\n<__>", "<.*>", "z")                          = "z"
+     * StringUtils.replacePattern("ABCabc123", "[a-z]", "_")                          = "ABC___123"
+     * StringUtils.replacePattern("ABCabc123", "[^A-Z0-9]+", "_")                     = "ABC_123"
+     * StringUtils.replacePattern("ABCabc123", "[^A-Z0-9]+", "")                      = "ABC123"
+     * StringUtils.replacePattern("Lorem ipsum  dolor   sit", "( +)([a-z]+)", "_$2")  = "Lorem_ipsum_dolor_sit"
+     * }
+ * + * @param source the source string. + * @param regex the regular expression to which this string is to be matched. + * @param replacement the string to be substituted for each match. + * @return The resulting {@link String}. + * @see #replaceAll(String, String, String) + * @see String#replaceAll(String, String) + * @see Pattern#DOTALL + * @since 3.2 + * @since 3.5 Changed {@code null} reference passed to this method is a no-op. + * @deprecated Use {@link RegExUtils#replacePattern(CharSequence, String, String)}. + */ + @Deprecated + public static String replacePattern(final String source, final String regex, final String replacement) { + return RegExUtils.replacePattern(source, regex, replacement); + } + + /** + * Reverses a String as per {@link StringBuilder#reverse()}. + * + *

+ * A {@code null} String returns {@code null}. + *

+ * + *
+     * StringUtils.reverse(null)  = null
+     * StringUtils.reverse("")    = ""
+     * StringUtils.reverse("bat") = "tab"
+     * 
+ * + * @param str the String to reverse, may be null. + * @return the reversed String, {@code null} if null String input. + */ + public static String reverse(final String str) { + if (str == null) { + return null; + } + return new StringBuilder(str).reverse().toString(); + } + + /** + * Reverses a String that is delimited by a specific character. + * + *

+ * The Strings between the delimiters are not reversed. Thus java.lang.String becomes String.lang.java (if the delimiter is {@code '.'}). + *

+ * + *
+     * StringUtils.reverseDelimited(null, *)      = null
+     * StringUtils.reverseDelimited("", *)        = ""
+     * StringUtils.reverseDelimited("a.b.c", 'x') = "a.b.c"
+     * StringUtils.reverseDelimited("a.b.c", ".") = "c.b.a"
+     * 
+ * + * @param str the String to reverse, may be null. + * @param separatorChar the separator character to use. + * @return the reversed String, {@code null} if null String input. + * @since 2.0 + */ + public static String reverseDelimited(final String str, final char separatorChar) { + final String[] strs = split(str, separatorChar); + ArrayUtils.reverse(strs); + return join(strs, separatorChar); + } + + /** + * Gets the rightmost {@code len} characters of a String. + * + *

+ * If {@code len} characters are not available, or the String is {@code null}, the String will be returned without an exception. An empty String is + * returned if len is negative. + *

+ * + *
+     * StringUtils.right(null, *)    = null
+     * StringUtils.right(*, -ve)     = ""
+     * StringUtils.right("", *)      = ""
+     * StringUtils.right("abc", 0)   = ""
+     * StringUtils.right("abc", 2)   = "bc"
+     * StringUtils.right("abc", 4)   = "abc"
+     * 
+ * + * @param str the String to get the rightmost characters from, may be null. + * @param len the length of the required String. + * @return the rightmost characters, {@code null} if null String input. + */ + public static String right(final String str, final int len) { + if (str == null) { + return null; + } + if (len < 0) { + return EMPTY; + } + if (str.length() <= len) { + return str; + } + return str.substring(str.length() - len); + } + + /** + * Right pad a String with spaces (' '). + * + *

+ * The String is padded to the size of {@code size}. + *

+ * + *
+     * StringUtils.rightPad(null, *)   = null
+     * StringUtils.rightPad("", 3)     = "   "
+     * StringUtils.rightPad("bat", 3)  = "bat"
+     * StringUtils.rightPad("bat", 5)  = "bat  "
+     * StringUtils.rightPad("bat", 1)  = "bat"
+     * StringUtils.rightPad("bat", -1) = "bat"
+     * 
+ * + * @param str the String to pad out, may be null. + * @param size the size to pad to. + * @return right padded String or original String if no padding is necessary, {@code null} if null String input. + */ + public static String rightPad(final String str, final int size) { + return rightPad(str, size, ' '); + } + + /** + * Right pad a String with a specified character. + * + *

+ * The String is padded to the size of {@code size}. + *

+ * + *
+     * StringUtils.rightPad(null, *, *)     = null
+     * StringUtils.rightPad("", 3, 'z')     = "zzz"
+     * StringUtils.rightPad("bat", 3, 'z')  = "bat"
+     * StringUtils.rightPad("bat", 5, 'z')  = "batzz"
+     * StringUtils.rightPad("bat", 1, 'z')  = "bat"
+     * StringUtils.rightPad("bat", -1, 'z') = "bat"
+     * 
+ * + * @param str the String to pad out, may be null. + * @param size the size to pad to. + * @param padChar the character to pad with. + * @return right padded String or original String if no padding is necessary, {@code null} if null String input. + * @since 2.0 + */ + public static String rightPad(final String str, final int size, final char padChar) { + if (str == null) { + return null; + } + final int pads = size - str.length(); + if (pads <= 0) { + return str; // returns original String when possible + } + if (pads > PAD_LIMIT) { + return rightPad(str, size, String.valueOf(padChar)); + } + return str.concat(repeat(padChar, pads)); + } + + /** + * Right pad a String with a specified String. + * + *

+ * The String is padded to the size of {@code size}. + *

+ * + *
+     * StringUtils.rightPad(null, *, *)      = null
+     * StringUtils.rightPad("", 3, "z")      = "zzz"
+     * StringUtils.rightPad("bat", 3, "yz")  = "bat"
+     * StringUtils.rightPad("bat", 5, "yz")  = "batyz"
+     * StringUtils.rightPad("bat", 8, "yz")  = "batyzyzy"
+     * StringUtils.rightPad("bat", 1, "yz")  = "bat"
+     * StringUtils.rightPad("bat", -1, "yz") = "bat"
+     * StringUtils.rightPad("bat", 5, null)  = "bat  "
+     * StringUtils.rightPad("bat", 5, "")    = "bat  "
+     * 
+ * + * @param str the String to pad out, may be null. + * @param size the size to pad to. + * @param padStr the String to pad with, null or empty treated as single space. + * @return right padded String or original String if no padding is necessary, {@code null} if null String input. + */ + public static String rightPad(final String str, final int size, String padStr) { + if (str == null) { + return null; + } + if (isEmpty(padStr)) { + padStr = SPACE; + } + final int padLen = padStr.length(); + final int strLen = str.length(); + final int pads = size - strLen; + if (pads <= 0) { + return str; // returns original String when possible + } + if (padLen == 1 && pads <= PAD_LIMIT) { + return rightPad(str, size, padStr.charAt(0)); + } + if (pads == padLen) { + return str.concat(padStr); + } + if (pads < padLen) { + return str.concat(padStr.substring(0, pads)); + } + final char[] padding = new char[pads]; + final char[] padChars = padStr.toCharArray(); + for (int i = 0; i < pads; i++) { + padding[i] = padChars[i % padLen]; + } + return str.concat(new String(padding)); + } + + /** + * Rotate (circular shift) a String of {@code shift} characters. + *
    + *
  • If {@code shift > 0}, right circular shift (ex : ABCDEF => FABCDE)
  • + *
  • If {@code shift < 0}, left circular shift (ex : ABCDEF => BCDEFA)
  • + *
+ * + *
+     * StringUtils.rotate(null, *)        = null
+     * StringUtils.rotate("", *)          = ""
+     * StringUtils.rotate("abcdefg", 0)   = "abcdefg"
+     * StringUtils.rotate("abcdefg", 2)   = "fgabcde"
+     * StringUtils.rotate("abcdefg", -2)  = "cdefgab"
+     * StringUtils.rotate("abcdefg", 7)   = "abcdefg"
+     * StringUtils.rotate("abcdefg", -7)  = "abcdefg"
+     * StringUtils.rotate("abcdefg", 9)   = "fgabcde"
+     * StringUtils.rotate("abcdefg", -9)  = "cdefgab"
+     * 
+ * + * @param str the String to rotate, may be null. + * @param shift number of time to shift (positive : right shift, negative : left shift). + * @return the rotated String, or the original String if {@code shift == 0}, or {@code null} if null String input. + * @since 3.5 + */ + public static String rotate(final String str, final int shift) { + if (str == null) { + return null; + } + final int strLen = str.length(); + if (shift == 0 || strLen == 0 || shift % strLen == 0) { + return str; + } + final StringBuilder builder = new StringBuilder(strLen); + final int offset = -(shift % strLen); + builder.append(substring(str, offset)); + builder.append(substring(str, 0, offset)); + return builder.toString(); + } + + /** + * Splits the provided text into an array, using whitespace as the separator. Whitespace is defined by {@link Character#isWhitespace(char)}. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as one separator. For more control over the split use the + * StrTokenizer class. + *

+ * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.split(null)       = null
+     * StringUtils.split("")         = []
+     * StringUtils.split("abc def")  = ["abc", "def"]
+     * StringUtils.split("abc  def") = ["abc", "def"]
+     * StringUtils.split(" abc ")    = ["abc"]
+     * 
+ * + * @param str the String to parse, may be null. + * @return an array of parsed Strings, {@code null} if null String input. + */ + public static String[] split(final String str) { + return split(str, null, -1); + } + + /** + * Splits the provided text into an array, separator specified. This is an alternative to using StringTokenizer. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as one separator. For more control over the split use the + * StrTokenizer class. + *

+ * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.split(null, *)         = null
+     * StringUtils.split("", *)           = []
+     * StringUtils.split("a.b.c", '.')    = ["a", "b", "c"]
+     * StringUtils.split("a..b.c", '.')   = ["a", "b", "c"]
+     * StringUtils.split("a:b:c", '.')    = ["a:b:c"]
+     * StringUtils.split("a b c", ' ')    = ["a", "b", "c"]
+     * 
+ * + * @param str the String to parse, may be null. + * @param separatorChar the character used as the delimiter. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.0 + */ + public static String[] split(final String str, final char separatorChar) { + return splitWorker(str, separatorChar, false); + } + + /** + * Splits the provided text into an array, separators specified. This is an alternative to using StringTokenizer. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as one separator. For more control over the split use the + * StrTokenizer class. + *

+ * + *

+ * A {@code null} input String returns {@code null}. A {@code null} separatorChars splits on whitespace. + *

+ * + *
+     * StringUtils.split(null, *)         = null
+     * StringUtils.split("", *)           = []
+     * StringUtils.split("abc def", null) = ["abc", "def"]
+     * StringUtils.split("abc def", " ")  = ["abc", "def"]
+     * StringUtils.split("abc  def", " ") = ["abc", "def"]
+     * StringUtils.split("ab:cd:ef", ":") = ["ab", "cd", "ef"]
+     * 
+ * + * @param str the String to parse, may be null. + * @param separatorChars the characters used as the delimiters, {@code null} splits on whitespace. + * @return an array of parsed Strings, {@code null} if null String input. + */ + public static String[] split(final String str, final String separatorChars) { + return splitWorker(str, separatorChars, -1, false); + } + + /** + * Splits the provided text into an array with a maximum length, separators specified. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as one separator. + *

+ * + *

+ * A {@code null} input String returns {@code null}. A {@code null} separatorChars splits on whitespace. + *

+ * + *

+ * If more than {@code max} delimited substrings are found, the last returned string includes all characters after the first {@code max - 1} returned + * strings (including separator characters). + *

+ * + *
+     * StringUtils.split(null, *, *)            = null
+     * StringUtils.split("", *, *)              = []
+     * StringUtils.split("ab cd ef", null, 0)   = ["ab", "cd", "ef"]
+     * StringUtils.split("ab   cd ef", null, 0) = ["ab", "cd", "ef"]
+     * StringUtils.split("ab:cd:ef", ":", 0)    = ["ab", "cd", "ef"]
+     * StringUtils.split("ab:cd:ef", ":", 2)    = ["ab", "cd:ef"]
+     * 
+ * + * @param str the String to parse, may be null. + * @param separatorChars the characters used as the delimiters, {@code null} splits on whitespace. + * @param max the maximum number of elements to include in the array. A zero or negative value implies no limit. + * @return an array of parsed Strings, {@code null} if null String input. + */ + public static String[] split(final String str, final String separatorChars, final int max) { + return splitWorker(str, separatorChars, max, false); + } + + /** + * Splits a String by Character type as returned by {@code java.lang.Character.getType(char)}. Groups of contiguous characters of the same type are returned + * as complete tokens. + * + *
+     * StringUtils.splitByCharacterType(null)         = null
+     * StringUtils.splitByCharacterType("")           = []
+     * StringUtils.splitByCharacterType("ab de fg")   = ["ab", " ", "de", " ", "fg"]
+     * StringUtils.splitByCharacterType("ab   de fg") = ["ab", "   ", "de", " ", "fg"]
+     * StringUtils.splitByCharacterType("ab:cd:ef")   = ["ab", ":", "cd", ":", "ef"]
+     * StringUtils.splitByCharacterType("number5")    = ["number", "5"]
+     * StringUtils.splitByCharacterType("fooBar")     = ["foo", "B", "ar"]
+     * StringUtils.splitByCharacterType("foo200Bar")  = ["foo", "200", "B", "ar"]
+     * StringUtils.splitByCharacterType("ASFRules")   = ["ASFR", "ules"]
+     * 
+ * + * @param str the String to split, may be {@code null}. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.4 + */ + public static String[] splitByCharacterType(final String str) { + return splitByCharacterType(str, false); + } + + /** + * Splits a String by Character type as returned by {@code java.lang.Character.getType(char)}. Groups of contiguous characters of the same type are returned + * as complete tokens, with the following exception: if {@code camelCase} is {@code true}, the character of type {@code Character.UPPERCASE_LETTER}, if any, + * immediately preceding a token of type {@code Character.LOWERCASE_LETTER} will belong to the following token rather than to the preceding, if any, + * {@code Character.UPPERCASE_LETTER} token. + * + * @param str the String to split, may be {@code null}. + * @param camelCase whether to use so-called "camel-case" for letter types. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.4 + */ + private static String[] splitByCharacterType(final String str, final boolean camelCase) { + if (str == null) { + return null; + } + if (str.isEmpty()) { + return ArrayUtils.EMPTY_STRING_ARRAY; + } + final char[] c = str.toCharArray(); + final List list = new ArrayList<>(); + int tokenStart = 0; + int currentType = Character.getType(c[tokenStart]); + for (int pos = tokenStart + 1; pos < c.length; pos++) { + final int type = Character.getType(c[pos]); + if (type == currentType) { + continue; + } + if (camelCase && type == Character.LOWERCASE_LETTER && currentType == Character.UPPERCASE_LETTER) { + final int newTokenStart = pos - 1; + if (newTokenStart != tokenStart) { + list.add(new String(c, tokenStart, newTokenStart - tokenStart)); + tokenStart = newTokenStart; + } + } else { + list.add(new String(c, tokenStart, pos - tokenStart)); + tokenStart = pos; + } + currentType = type; + } + list.add(new String(c, tokenStart, c.length - tokenStart)); + return list.toArray(ArrayUtils.EMPTY_STRING_ARRAY); + } + + /** + * Splits a String by Character type as returned by {@code java.lang.Character.getType(char)}. Groups of contiguous characters of the same type are returned + * as complete tokens, with the following exception: the character of type {@code Character.UPPERCASE_LETTER}, if any, immediately preceding a token of type + * {@code Character.LOWERCASE_LETTER} will belong to the following token rather than to the preceding, if any, {@code Character.UPPERCASE_LETTER} token. + * + *
+     * StringUtils.splitByCharacterTypeCamelCase(null)         = null
+     * StringUtils.splitByCharacterTypeCamelCase("")           = []
+     * StringUtils.splitByCharacterTypeCamelCase("ab de fg")   = ["ab", " ", "de", " ", "fg"]
+     * StringUtils.splitByCharacterTypeCamelCase("ab   de fg") = ["ab", "   ", "de", " ", "fg"]
+     * StringUtils.splitByCharacterTypeCamelCase("ab:cd:ef")   = ["ab", ":", "cd", ":", "ef"]
+     * StringUtils.splitByCharacterTypeCamelCase("number5")    = ["number", "5"]
+     * StringUtils.splitByCharacterTypeCamelCase("fooBar")     = ["foo", "Bar"]
+     * StringUtils.splitByCharacterTypeCamelCase("foo200Bar")  = ["foo", "200", "Bar"]
+     * StringUtils.splitByCharacterTypeCamelCase("ASFRules")   = ["ASF", "Rules"]
+     * 
+ * + * @param str the String to split, may be {@code null}. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.4 + */ + public static String[] splitByCharacterTypeCamelCase(final String str) { + return splitByCharacterType(str, true); + } + + /** + * Splits the provided text into an array, separator string specified. + * + *

+ * The separator(s) will not be included in the returned String array. Adjacent separators are treated as one separator. + *

+ * + *

+ * A {@code null} input String returns {@code null}. A {@code null} separator splits on whitespace. + *

+ * + *
+     * StringUtils.splitByWholeSeparator(null, *)               = null
+     * StringUtils.splitByWholeSeparator("", *)                 = []
+     * StringUtils.splitByWholeSeparator("ab de fg", null)      = ["ab", "de", "fg"]
+     * StringUtils.splitByWholeSeparator("ab   de fg", null)    = ["ab", "de", "fg"]
+     * StringUtils.splitByWholeSeparator("ab:cd:ef", ":")       = ["ab", "cd", "ef"]
+     * StringUtils.splitByWholeSeparator("ab-!-cd-!-ef", "-!-") = ["ab", "cd", "ef"]
+     * 
+ * + * @param str the String to parse, may be null. + * @param separator String containing the String to be used as a delimiter, {@code null} splits on whitespace. + * @return an array of parsed Strings, {@code null} if null String was input. + */ + public static String[] splitByWholeSeparator(final String str, final String separator) { + return splitByWholeSeparatorWorker(str, separator, -1, false); + } + + /** + * Splits the provided text into an array, separator string specified. Returns a maximum of {@code max} substrings. + * + *

+ * The separator(s) will not be included in the returned String array. Adjacent separators are treated as one separator. + *

+ * + *

+ * A {@code null} input String returns {@code null}. A {@code null} separator splits on whitespace. + *

+ * + *
+     * StringUtils.splitByWholeSeparator(null, *, *)               = null
+     * StringUtils.splitByWholeSeparator("", *, *)                 = []
+     * StringUtils.splitByWholeSeparator("ab de fg", null, 0)      = ["ab", "de", "fg"]
+     * StringUtils.splitByWholeSeparator("ab   de fg", null, 0)    = ["ab", "de", "fg"]
+     * StringUtils.splitByWholeSeparator("ab:cd:ef", ":", 2)       = ["ab", "cd:ef"]
+     * StringUtils.splitByWholeSeparator("ab-!-cd-!-ef", "-!-", 5) = ["ab", "cd", "ef"]
+     * StringUtils.splitByWholeSeparator("ab-!-cd-!-ef", "-!-", 2) = ["ab", "cd-!-ef"]
+     * 
+ * + * @param str the String to parse, may be null. + * @param separator String containing the String to be used as a delimiter, {@code null} splits on whitespace. + * @param max the maximum number of elements to include in the returned array. A zero or negative value implies no limit. + * @return an array of parsed Strings, {@code null} if null String was input. + */ + public static String[] splitByWholeSeparator(final String str, final String separator, final int max) { + return splitByWholeSeparatorWorker(str, separator, max, false); + } + + /** + * Splits the provided text into an array, separator string specified. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as separators for empty tokens. For more control over the + * split use the StrTokenizer class. + *

+ * + *

+ * A {@code null} input String returns {@code null}. A {@code null} separator splits on whitespace. + *

+ * + *
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens(null, *)               = null
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("", *)                 = []
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab de fg", null)      = ["ab", "de", "fg"]
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab   de fg", null)    = ["ab", "", "", "de", "fg"]
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab:cd:ef", ":")       = ["ab", "cd", "ef"]
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab-!-cd-!-ef", "-!-") = ["ab", "cd", "ef"]
+     * 
+ * + * @param str the String to parse, may be null. + * @param separator String containing the String to be used as a delimiter, {@code null} splits on whitespace. + * @return an array of parsed Strings, {@code null} if null String was input. + * @since 2.4 + */ + public static String[] splitByWholeSeparatorPreserveAllTokens(final String str, final String separator) { + return splitByWholeSeparatorWorker(str, separator, -1, true); + } + + /** + * Splits the provided text into an array, separator string specified. Returns a maximum of {@code max} substrings. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as separators for empty tokens. For more control over the + * split use the StrTokenizer class. + *

+ * + *

+ * A {@code null} input String returns {@code null}. A {@code null} separator splits on whitespace. + *

+ * + *
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens(null, *, *)               = null
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("", *, *)                 = []
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab de fg", null, 0)      = ["ab", "de", "fg"]
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab   de fg", null, 0)    = ["ab", "", "", "de", "fg"]
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab:cd:ef", ":", 2)       = ["ab", "cd:ef"]
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab-!-cd-!-ef", "-!-", 5) = ["ab", "cd", "ef"]
+     * StringUtils.splitByWholeSeparatorPreserveAllTokens("ab-!-cd-!-ef", "-!-", 2) = ["ab", "cd-!-ef"]
+     * 
+ * + * @param str the String to parse, may be null. + * @param separator String containing the String to be used as a delimiter, {@code null} splits on whitespace. + * @param max the maximum number of elements to include in the returned array. A zero or negative value implies no limit. + * @return an array of parsed Strings, {@code null} if null String was input. + * @since 2.4 + */ + public static String[] splitByWholeSeparatorPreserveAllTokens(final String str, final String separator, final int max) { + return splitByWholeSeparatorWorker(str, separator, max, true); + } + + /** + * Performs the logic for the {@code splitByWholeSeparatorPreserveAllTokens} methods. + * + * @param str the String to parse, may be {@code null}. + * @param separator String containing the String to be used as a delimiter, {@code null} splits on whitespace. + * @param max the maximum number of elements to include in the returned array. A zero or negative value implies no limit. + * @param preserveAllTokens if {@code true}, adjacent separators are treated as empty token separators; if {@code false}, adjacent separators are treated as + * one separator. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.4 + */ + private static String[] splitByWholeSeparatorWorker(final String str, final String separator, final int max, final boolean preserveAllTokens) { + if (str == null) { + return null; + } + final int len = str.length(); + if (len == 0) { + return ArrayUtils.EMPTY_STRING_ARRAY; + } + if (separator == null || EMPTY.equals(separator)) { + // Split on whitespace. + return splitWorker(str, null, max, preserveAllTokens); + } + final int separatorLength = separator.length(); + final ArrayList substrings = new ArrayList<>(); + int numberOfSubstrings = 0; + int beg = 0; + int end = 0; + while (end < len) { + end = str.indexOf(separator, beg); + if (end > -1) { + if (end > beg) { + numberOfSubstrings += 1; + if (numberOfSubstrings == max) { + end = len; + substrings.add(str.substring(beg)); + } else { + // The following is OK, because String.substring( beg, end ) excludes + // the character at the position 'end'. + substrings.add(str.substring(beg, end)); + // Set the starting point for the next search. + // The following is equivalent to beg = end + (separatorLength - 1) + 1, + // which is the right calculation: + beg = end + separatorLength; + } + } else { + // We found a consecutive occurrence of the separator, so skip it. + if (preserveAllTokens) { + numberOfSubstrings += 1; + if (numberOfSubstrings == max) { + end = len; + substrings.add(str.substring(beg)); + } else { + substrings.add(EMPTY); + } + } + beg = end + separatorLength; + } + } else { + // String.substring( beg ) goes from 'beg' to the end of the String. + substrings.add(str.substring(beg)); + end = len; + } + } + return substrings.toArray(ArrayUtils.EMPTY_STRING_ARRAY); + } + + /** + * Splits the provided text into an array, using whitespace as the separator, preserving all tokens, including empty tokens created by adjacent separators. + * This is an alternative to using StringTokenizer. Whitespace is defined by {@link Character#isWhitespace(char)}. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as separators for empty tokens. For more control over the + * split use the StrTokenizer class. + *

+ * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.splitPreserveAllTokens(null)       = null
+     * StringUtils.splitPreserveAllTokens("")         = []
+     * StringUtils.splitPreserveAllTokens("abc def")  = ["abc", "def"]
+     * StringUtils.splitPreserveAllTokens("abc  def") = ["abc", "", "def"]
+     * StringUtils.splitPreserveAllTokens(" abc ")    = ["", "abc", ""]
+     * 
+ * + * @param str the String to parse, may be {@code null}. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.1 + */ + public static String[] splitPreserveAllTokens(final String str) { + return splitWorker(str, null, -1, true); + } + + /** + * Splits the provided text into an array, separator specified, preserving all tokens, including empty tokens created by adjacent separators. This is an + * alternative to using StringTokenizer. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as separators for empty tokens. For more control over the + * split use the StrTokenizer class. + *

+ * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.splitPreserveAllTokens(null, *)         = null
+     * StringUtils.splitPreserveAllTokens("", *)           = []
+     * StringUtils.splitPreserveAllTokens("a.b.c", '.')    = ["a", "b", "c"]
+     * StringUtils.splitPreserveAllTokens("a..b.c", '.')   = ["a", "", "b", "c"]
+     * StringUtils.splitPreserveAllTokens("a:b:c", '.')    = ["a:b:c"]
+     * StringUtils.splitPreserveAllTokens("a\tb\nc", null) = ["a", "b", "c"]
+     * StringUtils.splitPreserveAllTokens("a b c", ' ')    = ["a", "b", "c"]
+     * StringUtils.splitPreserveAllTokens("a b c ", ' ')   = ["a", "b", "c", ""]
+     * StringUtils.splitPreserveAllTokens("a b c  ", ' ')  = ["a", "b", "c", "", ""]
+     * StringUtils.splitPreserveAllTokens(" a b c", ' ')   = ["", "a", "b", "c"]
+     * StringUtils.splitPreserveAllTokens("  a b c", ' ')  = ["", "", "a", "b", "c"]
+     * StringUtils.splitPreserveAllTokens(" a b c ", ' ')  = ["", "a", "b", "c", ""]
+     * 
+ * + * @param str the String to parse, may be {@code null}. + * @param separatorChar the character used as the delimiter, {@code null} splits on whitespace. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.1 + */ + public static String[] splitPreserveAllTokens(final String str, final char separatorChar) { + return splitWorker(str, separatorChar, true); + } + + /** + * Splits the provided text into an array, separators specified, preserving all tokens, including empty tokens created by adjacent separators. This is an + * alternative to using StringTokenizer. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as separators for empty tokens. For more control over the + * split use the StrTokenizer class. + *

+ * + *

+ * A {@code null} input String returns {@code null}. A {@code null} separatorChars splits on whitespace. + *

+ * + *
+     * StringUtils.splitPreserveAllTokens(null, *)           = null
+     * StringUtils.splitPreserveAllTokens("", *)             = []
+     * StringUtils.splitPreserveAllTokens("abc def", null)   = ["abc", "def"]
+     * StringUtils.splitPreserveAllTokens("abc def", " ")    = ["abc", "def"]
+     * StringUtils.splitPreserveAllTokens("abc  def", " ")   = ["abc", "", "def"]
+     * StringUtils.splitPreserveAllTokens("ab:cd:ef", ":")   = ["ab", "cd", "ef"]
+     * StringUtils.splitPreserveAllTokens("ab:cd:ef:", ":")  = ["ab", "cd", "ef", ""]
+     * StringUtils.splitPreserveAllTokens("ab:cd:ef::", ":") = ["ab", "cd", "ef", "", ""]
+     * StringUtils.splitPreserveAllTokens("ab::cd:ef", ":")  = ["ab", "", "cd", "ef"]
+     * StringUtils.splitPreserveAllTokens(":cd:ef", ":")     = ["", "cd", "ef"]
+     * StringUtils.splitPreserveAllTokens("::cd:ef", ":")    = ["", "", "cd", "ef"]
+     * StringUtils.splitPreserveAllTokens(":cd:ef:", ":")    = ["", "cd", "ef", ""]
+     * 
+ * + * @param str the String to parse, may be {@code null}. + * @param separatorChars the characters used as the delimiters, {@code null} splits on whitespace. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.1 + */ + public static String[] splitPreserveAllTokens(final String str, final String separatorChars) { + return splitWorker(str, separatorChars, -1, true); + } + + /** + * Splits the provided text into an array with a maximum length, separators specified, preserving all tokens, including empty tokens created by adjacent + * separators. + * + *

+ * The separator is not included in the returned String array. Adjacent separators are treated as separators for empty tokens. Adjacent separators are + * treated as one separator. + *

+ * + *

+ * A {@code null} input String returns {@code null}. A {@code null} separatorChars splits on whitespace. + *

+ * + *

+ * If more than {@code max} delimited substrings are found, the last returned string includes all characters after the first {@code max - 1} returned + * strings (including separator characters). + *

+ * + *
+     * StringUtils.splitPreserveAllTokens(null, *, *)            = null
+     * StringUtils.splitPreserveAllTokens("", *, *)              = []
+     * StringUtils.splitPreserveAllTokens("ab de fg", null, 0)   = ["ab", "de", "fg"]
+     * StringUtils.splitPreserveAllTokens("ab   de fg", null, 0) = ["ab", "", "", "de", "fg"]
+     * StringUtils.splitPreserveAllTokens("ab:cd:ef", ":", 0)    = ["ab", "cd", "ef"]
+     * StringUtils.splitPreserveAllTokens("ab:cd:ef", ":", 2)    = ["ab", "cd:ef"]
+     * StringUtils.splitPreserveAllTokens("ab   de fg", null, 2) = ["ab", "  de fg"]
+     * StringUtils.splitPreserveAllTokens("ab   de fg", null, 3) = ["ab", "", " de fg"]
+     * StringUtils.splitPreserveAllTokens("ab   de fg", null, 4) = ["ab", "", "", "de fg"]
+     * 
+ * + * @param str the String to parse, may be {@code null}. + * @param separatorChars the characters used as the delimiters, {@code null} splits on whitespace. + * @param max the maximum number of elements to include in the array. A zero or negative value implies no limit. + * @return an array of parsed Strings, {@code null} if null String input. + * @since 2.1 + */ + public static String[] splitPreserveAllTokens(final String str, final String separatorChars, final int max) { + return splitWorker(str, separatorChars, max, true); + } + + /** + * Performs the logic for the {@code split} and {@code splitPreserveAllTokens} methods that do not return a maximum array length. + * + * @param str the String to parse, may be {@code null}. + * @param separatorChar the separate character. + * @param preserveAllTokens if {@code true}, adjacent separators are treated as empty token separators; if {@code false}, adjacent separators are treated as + * one separator. + * @return an array of parsed Strings, {@code null} if null String input. + */ + private static String[] splitWorker(final String str, final char separatorChar, final boolean preserveAllTokens) { + // Performance tuned for 2.0 (JDK1.4) + if (str == null) { + return null; + } + final int len = str.length(); + if (len == 0) { + return ArrayUtils.EMPTY_STRING_ARRAY; + } + final List list = new ArrayList<>(); + int i = 0; + int start = 0; + boolean match = false; + boolean lastMatch = false; + while (i < len) { + if (str.charAt(i) == separatorChar) { + if (match || preserveAllTokens) { + list.add(str.substring(start, i)); + match = false; + lastMatch = true; + } + start = ++i; + continue; + } + lastMatch = false; + match = true; + i++; + } + if (match || preserveAllTokens && lastMatch) { + list.add(str.substring(start, i)); + } + return list.toArray(ArrayUtils.EMPTY_STRING_ARRAY); + } + + /** + * Performs the logic for the {@code split} and {@code splitPreserveAllTokens} methods that return a maximum array length. + * + * @param str the String to parse, may be {@code null}. + * @param separatorChars the separate character. + * @param max the maximum number of elements to include in the array. A zero or negative value implies no limit. + * @param preserveAllTokens if {@code true}, adjacent separators are treated as empty token separators; if {@code false}, adjacent separators are treated as + * one separator. + * @return an array of parsed Strings, {@code null} if null String input. + */ + private static String[] splitWorker(final String str, final String separatorChars, final int max, final boolean preserveAllTokens) { + // Performance tuned for 2.0 (JDK1.4) + // Direct code is quicker than StringTokenizer. + // Also, StringTokenizer uses isSpace() not isWhitespace() + if (str == null) { + return null; + } + final int len = str.length(); + if (len == 0) { + return ArrayUtils.EMPTY_STRING_ARRAY; + } + final List list = new ArrayList<>(); + int sizePlus1 = 1; + int i = 0; + int start = 0; + boolean match = false; + boolean lastMatch = false; + if (separatorChars == null) { + // Null separator means use whitespace + while (i < len) { + if (Character.isWhitespace(str.charAt(i))) { + if (match || preserveAllTokens) { + lastMatch = true; + if (sizePlus1++ == max) { + i = len; + lastMatch = false; + } + list.add(str.substring(start, i)); + match = false; + } + start = ++i; + continue; + } + lastMatch = false; + match = true; + i++; + } + } else if (separatorChars.length() == 1) { + // Optimize 1 character case + final char sep = separatorChars.charAt(0); + while (i < len) { + if (str.charAt(i) == sep) { + if (match || preserveAllTokens) { + lastMatch = true; + if (sizePlus1++ == max) { + i = len; + lastMatch = false; + } + list.add(str.substring(start, i)); + match = false; + } + start = ++i; + continue; + } + lastMatch = false; + match = true; + i++; + } + } else { + // standard case + while (i < len) { + if (separatorChars.indexOf(str.charAt(i)) >= 0) { + if (match || preserveAllTokens) { + lastMatch = true; + if (sizePlus1++ == max) { + i = len; + lastMatch = false; + } + list.add(str.substring(start, i)); + match = false; + } + start = ++i; + continue; + } + lastMatch = false; + match = true; + i++; + } + } + if (match || preserveAllTokens && lastMatch) { + list.add(str.substring(start, i)); + } + return list.toArray(ArrayUtils.EMPTY_STRING_ARRAY); + } + + /** + * Tests if a CharSequence starts with a specified prefix. + * + *

+ * {@code null}s are handled without exceptions. Two {@code null} references are considered to be equal. The comparison is case-sensitive. + *

+ * + *
+     * StringUtils.startsWith(null, null)      = true
+     * StringUtils.startsWith(null, "abc")     = false
+     * StringUtils.startsWith("abcdef", null)  = false
+     * StringUtils.startsWith("abcdef", "abc") = true
+     * StringUtils.startsWith("ABCDEF", "abc") = false
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param prefix the prefix to find, may be null. + * @return {@code true} if the CharSequence starts with the prefix, case-sensitive, or both {@code null}. + * @see String#startsWith(String) + * @since 2.4 + * @since 3.0 Changed signature from startsWith(String, String) to startsWith(CharSequence, CharSequence) + * @deprecated Use {@link Strings#startsWith(CharSequence, CharSequence) Strings.CS.startsWith(CharSequence, CharSequence)}. + */ + @Deprecated + public static boolean startsWith(final CharSequence str, final CharSequence prefix) { + return Strings.CS.startsWith(str, prefix); + } + + /** + * Tests if a CharSequence starts with any of the provided case-sensitive prefixes. + * + *
+     * StringUtils.startsWithAny(null, null)      = false
+     * StringUtils.startsWithAny(null, new String[] {"abc"})  = false
+     * StringUtils.startsWithAny("abcxyz", null)     = false
+     * StringUtils.startsWithAny("abcxyz", new String[] {""}) = true
+     * StringUtils.startsWithAny("abcxyz", new String[] {"abc"}) = true
+     * StringUtils.startsWithAny("abcxyz", new String[] {null, "xyz", "abc"}) = true
+     * StringUtils.startsWithAny("abcxyz", null, "xyz", "ABCX") = false
+     * StringUtils.startsWithAny("ABCXYZ", null, "xyz", "abc") = false
+     * 
+ * + * @param sequence the CharSequence to check, may be null. + * @param searchStrings the case-sensitive CharSequence prefixes, may be empty or contain {@code null}. + * @return {@code true} if the input {@code sequence} is {@code null} AND no {@code searchStrings} are provided, or the input {@code sequence} begins with + * any of the provided case-sensitive {@code searchStrings}. + * @see StringUtils#startsWith(CharSequence, CharSequence) + * @since 2.5 + * @since 3.0 Changed signature from startsWithAny(String, String[]) to startsWithAny(CharSequence, CharSequence...) + * @deprecated Use {@link Strings#startsWithAny(CharSequence, CharSequence...) Strings.CS.startsWithAny(CharSequence, CharSequence...)}. + */ + @Deprecated + public static boolean startsWithAny(final CharSequence sequence, final CharSequence... searchStrings) { + return Strings.CS.startsWithAny(sequence, searchStrings); + } + + /** + * Case-insensitive check if a CharSequence starts with a specified prefix. + * + *

+ * {@code null}s are handled without exceptions. Two {@code null} references are considered to be equal. The comparison is case insensitive. + *

+ * + *
+     * StringUtils.startsWithIgnoreCase(null, null)      = true
+     * StringUtils.startsWithIgnoreCase(null, "abc")     = false
+     * StringUtils.startsWithIgnoreCase("abcdef", null)  = false
+     * StringUtils.startsWithIgnoreCase("abcdef", "abc") = true
+     * StringUtils.startsWithIgnoreCase("ABCDEF", "abc") = true
+     * 
+ * + * @param str the CharSequence to check, may be null. + * @param prefix the prefix to find, may be null. + * @return {@code true} if the CharSequence starts with the prefix, case-insensitive, or both {@code null}. + * @see String#startsWith(String) + * @since 2.4 + * @since 3.0 Changed signature from startsWithIgnoreCase(String, String) to startsWithIgnoreCase(CharSequence, CharSequence) + * @deprecated Use {@link Strings#startsWith(CharSequence, CharSequence) Strings.CI.startsWith(CharSequence, CharSequence)}. + */ + @Deprecated + public static boolean startsWithIgnoreCase(final CharSequence str, final CharSequence prefix) { + return Strings.CI.startsWith(str, prefix); + } + + /** + * Strips whitespace from the start and end of a String. + * + *

+ * This is similar to {@link #trim(String)} but removes whitespace. Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.strip(null)     = null
+     * StringUtils.strip("")       = ""
+     * StringUtils.strip("   ")    = ""
+     * StringUtils.strip("abc")    = "abc"
+     * StringUtils.strip("  abc")  = "abc"
+     * StringUtils.strip("abc  ")  = "abc"
+     * StringUtils.strip(" abc ")  = "abc"
+     * StringUtils.strip(" ab c ") = "ab c"
+     * 
+ * + * @param str the String to remove whitespace from, may be null. + * @return the stripped String, {@code null} if null String input. + */ + public static String strip(final String str) { + return strip(str, null); + } + + /** + * Strips any of a set of characters from the start and end of a String. This is similar to {@link String#trim()} but allows the characters to be stripped + * to be controlled. + * + *

+ * A {@code null} input String returns {@code null}. An empty string ("") input returns the empty string. + *

+ * + *

+ * If the stripChars String is {@code null}, whitespace is stripped as defined by {@link Character#isWhitespace(char)}. Alternatively use + * {@link #strip(String)}. + *

+ * + *
+     * StringUtils.strip(null, *)          = null
+     * StringUtils.strip("", *)            = ""
+     * StringUtils.strip("abc", null)      = "abc"
+     * StringUtils.strip("  abc", null)    = "abc"
+     * StringUtils.strip("abc  ", null)    = "abc"
+     * StringUtils.strip(" abc ", null)    = "abc"
+     * StringUtils.strip("  abcyx", "xyz") = "  abc"
+     * 
+ * + * @param str the String to remove characters from, may be null. + * @param stripChars the characters to remove, null treated as whitespace. + * @return the stripped String, {@code null} if null String input. + */ + public static String strip(String str, final String stripChars) { + str = stripStart(str, stripChars); + return stripEnd(str, stripChars); + } + + /** + * Removes diacritics (~= accents) from a string. The case will not be altered. + *

+ * For instance, 'à' will be replaced by 'a'. + *

+ *

+ * Decomposes ligatures and digraphs per the KD column in the Unicode Normalization Chart. + *

+ * + *
+     * StringUtils.stripAccents(null)         = null
+     * StringUtils.stripAccents("")           = ""
+     * StringUtils.stripAccents("control")    = "control"
+     * StringUtils.stripAccents("éclair")     = "eclair"
+     * StringUtils.stripAccents("\u1d43\u1d47\u1d9c\u00b9\u00b2\u00b3")     = "abc123"
+     * StringUtils.stripAccents("\u00BC \u00BD \u00BE")      = "1⁄4 1⁄2 3⁄4"
+     * 
+ *

+ * See also Unicode Standard Annex #15 Unicode Normalization Forms. + *

+ * + * @param input String to be stripped. + * @return input text with diacritics removed. + * @since 3.0 + */ + // See also Lucene's ASCIIFoldingFilter (Lucene 2.9) that replaces accented characters by their unaccented equivalent (and uncommitted bug fix: + // https://issues.apache.org/jira/browse/LUCENE-1343?focusedCommentId=12858907&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#action_12858907). + public static String stripAccents(final String input) { + if (isEmpty(input)) { + return input; + } + final StringBuilder decomposed = new StringBuilder(Normalizer.normalize(input, Normalizer.Form.NFKD)); + convertRemainingAccentCharacters(decomposed); + return STRIP_ACCENTS_PATTERN.matcher(decomposed).replaceAll(EMPTY); + } + + /** + * Strips whitespace from the start and end of every String in an array. Whitespace is defined by {@link Character#isWhitespace(char)}. + * + *

+ * A new array is returned each time, except for length zero. A {@code null} array will return {@code null}. An empty array will return itself. A + * {@code null} array entry will be ignored. + *

+ * + *
+     * StringUtils.stripAll(null)             = null
+     * StringUtils.stripAll([])               = []
+     * StringUtils.stripAll(["abc", "  abc"]) = ["abc", "abc"]
+     * StringUtils.stripAll(["abc  ", null])  = ["abc", null]
+     * 
+ * + * @param strs the array to remove whitespace from, may be null. + * @return the stripped Strings, {@code null} if null array input. + */ + public static String[] stripAll(final String... strs) { + return stripAll(strs, null); + } + + /** + * Strips any of a set of characters from the start and end of every String in an array. + *

+ * Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *

+ * A new array is returned each time, except for length zero. A {@code null} array will return {@code null}. An empty array will return itself. A + * {@code null} array entry will be ignored. A {@code null} stripChars will strip whitespace as defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.stripAll(null, *)                = null
+     * StringUtils.stripAll([], *)                  = []
+     * StringUtils.stripAll(["abc", "  abc"], null) = ["abc", "abc"]
+     * StringUtils.stripAll(["abc  ", null], null)  = ["abc", null]
+     * StringUtils.stripAll(["abc  ", null], "yz")  = ["abc  ", null]
+     * StringUtils.stripAll(["yabcz", null], "yz")  = ["abc", null]
+     * 
+ * + * @param strs the array to remove characters from, may be null. + * @param stripChars the characters to remove, null treated as whitespace. + * @return the stripped Strings, {@code null} if null array input. + */ + public static String[] stripAll(final String[] strs, final String stripChars) { + final int strsLen = ArrayUtils.getLength(strs); + if (strsLen == 0) { + return strs; + } + return ArrayUtils.setAll(new String[strsLen], i -> strip(strs[i], stripChars)); + } + + /** + * Strips any of a set of characters from the end of a String. + * + *

+ * A {@code null} input String returns {@code null}. An empty string ("") input returns the empty string. + *

+ * + *

+ * If the stripChars String is {@code null}, whitespace is stripped as defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.stripEnd(null, *)          = null
+     * StringUtils.stripEnd("", *)            = ""
+     * StringUtils.stripEnd("abc", "")        = "abc"
+     * StringUtils.stripEnd("abc", null)      = "abc"
+     * StringUtils.stripEnd("  abc", null)    = "  abc"
+     * StringUtils.stripEnd("abc  ", null)    = "abc"
+     * StringUtils.stripEnd(" abc ", null)    = " abc"
+     * StringUtils.stripEnd("  abcyx", "xyz") = "  abc"
+     * StringUtils.stripEnd("120.00", ".0")   = "12"
+     * 
+ * + * @param str the String to remove characters from, may be null. + * @param stripChars the set of characters to remove, null treated as whitespace. + * @return the stripped String, {@code null} if null String input. + */ + public static String stripEnd(final String str, final String stripChars) { + int end = length(str); + if (end == 0) { + return str; + } + if (stripChars == null) { + while (end != 0 && Character.isWhitespace(str.charAt(end - 1))) { + end--; + } + } else if (stripChars.isEmpty()) { + return str; + } else { + while (end != 0 && stripChars.indexOf(str.charAt(end - 1)) != INDEX_NOT_FOUND) { + end--; + } + } + return str.substring(0, end); + } + + /** + * Strips any of a set of characters from the start of a String. + * + *

+ * A {@code null} input String returns {@code null}. An empty string ("") input returns the empty string. + *

+ * + *

+ * If the stripChars String is {@code null}, whitespace is stripped as defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.stripStart(null, *)          = null
+     * StringUtils.stripStart("", *)            = ""
+     * StringUtils.stripStart("abc", "")        = "abc"
+     * StringUtils.stripStart("abc", null)      = "abc"
+     * StringUtils.stripStart("  abc", null)    = "abc"
+     * StringUtils.stripStart("abc  ", null)    = "abc  "
+     * StringUtils.stripStart(" abc ", null)    = "abc "
+     * StringUtils.stripStart("yxabc  ", "xyz") = "abc  "
+     * 
+ * + * @param str the String to remove characters from, may be null. + * @param stripChars the characters to remove, null treated as whitespace. + * @return the stripped String, {@code null} if null String input. + */ + public static String stripStart(final String str, final String stripChars) { + final int strLen = length(str); + if (strLen == 0) { + return str; + } + int start = 0; + if (stripChars == null) { + while (start != strLen && Character.isWhitespace(str.charAt(start))) { + start++; + } + } else if (stripChars.isEmpty()) { + return str; + } else { + while (start != strLen && stripChars.indexOf(str.charAt(start)) != INDEX_NOT_FOUND) { + start++; + } + } + return str.substring(start); + } + + /** + * Strips whitespace from the start and end of a String returning an empty String if {@code null} input. + * + *

+ * This is similar to {@link #trimToEmpty(String)} but removes whitespace. Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.stripToEmpty(null)     = ""
+     * StringUtils.stripToEmpty("")       = ""
+     * StringUtils.stripToEmpty("   ")    = ""
+     * StringUtils.stripToEmpty("abc")    = "abc"
+     * StringUtils.stripToEmpty("  abc")  = "abc"
+     * StringUtils.stripToEmpty("abc  ")  = "abc"
+     * StringUtils.stripToEmpty(" abc ")  = "abc"
+     * StringUtils.stripToEmpty(" ab c ") = "ab c"
+     * 
+ * + * @param str the String to be stripped, may be null. + * @return the trimmed String, or an empty String if {@code null} input. + * @since 2.0 + */ + public static String stripToEmpty(final String str) { + return str == null ? EMPTY : strip(str, null); + } + + /** + * Strips whitespace from the start and end of a String returning {@code null} if the String is empty ("") after the strip. + * + *

+ * This is similar to {@link #trimToNull(String)} but removes whitespace. Whitespace is defined by {@link Character#isWhitespace(char)}. + *

+ * + *
+     * StringUtils.stripToNull(null)     = null
+     * StringUtils.stripToNull("")       = null
+     * StringUtils.stripToNull("   ")    = null
+     * StringUtils.stripToNull("abc")    = "abc"
+     * StringUtils.stripToNull("  abc")  = "abc"
+     * StringUtils.stripToNull("abc  ")  = "abc"
+     * StringUtils.stripToNull(" abc ")  = "abc"
+     * StringUtils.stripToNull(" ab c ") = "ab c"
+     * 
+ * + * @param str the String to be stripped, may be null. + * @return the stripped String, {@code null} if whitespace, empty or null String input. + * @since 2.0 + */ + public static String stripToNull(String str) { + if (str == null) { + return null; + } + str = strip(str, null); + return str.isEmpty() ? null : str; // NOSONARLINT str cannot be null here + } + + /** + * Gets a substring from the specified String avoiding exceptions. + * + *

+ * A negative start position can be used to start {@code n} characters from the end of the String. + *

+ * + *

+ * A {@code null} String will return {@code null}. An empty ("") String will return "". + *

+ * + *
+     * StringUtils.substring(null, *)   = null
+     * StringUtils.substring("", *)     = ""
+     * StringUtils.substring("abc", 0)  = "abc"
+     * StringUtils.substring("abc", 2)  = "c"
+     * StringUtils.substring("abc", 4)  = ""
+     * StringUtils.substring("abc", -2) = "bc"
+     * StringUtils.substring("abc", -4) = "abc"
+     * 
+ * + * @param str the String to get the substring from, may be null. + * @param start the position to start from, negative means count back from the end of the String by this many characters. + * @return substring from start position, {@code null} if null String input. + */ + public static String substring(final String str, int start) { + if (str == null) { + return null; + } + // handle negatives, which means last n characters + if (start < 0) { + start = str.length() + start; // remember start is negative + } + if (start < 0) { + start = 0; + } + if (start > str.length()) { + return EMPTY; + } + return str.substring(start); + } + + /** + * Gets a substring from the specified String avoiding exceptions. + * + *

+ * A negative start position can be used to start/end {@code n} characters from the end of the String. + *

+ * + *

+ * The returned substring starts with the character in the {@code start} position and ends before the {@code end} position. All position counting is + * zero-based -- i.e., to start at the beginning of the string use {@code start = 0}. Negative start and end positions can be used to specify offsets + * relative to the end of the String. + *

+ * + *

+ * If {@code start} is not strictly to the left of {@code end}, "" is returned. + *

+ * + *
+     * StringUtils.substring(null, *, *)    = null
+     * StringUtils.substring("", * ,  *)    = "";
+     * StringUtils.substring("abc", 0, 2)   = "ab"
+     * StringUtils.substring("abc", 2, 0)   = ""
+     * StringUtils.substring("abc", 2, 4)   = "c"
+     * StringUtils.substring("abc", 4, 6)   = ""
+     * StringUtils.substring("abc", 2, 2)   = ""
+     * StringUtils.substring("abc", -2, -1) = "b"
+     * StringUtils.substring("abc", -4, 2)  = "ab"
+     * 
+ * + * @param str the String to get the substring from, may be null. + * @param start the position to start from, negative means count back from the end of the String by this many characters. + * @param end the position to end at (exclusive), negative means count back from the end of the String by this many characters. + * @return substring from start position to end position, {@code null} if null String input. + */ + public static String substring(final String str, int start, int end) { + if (str == null) { + return null; + } + // handle negatives + if (end < 0) { + end = str.length() + end; // remember end is negative + } + if (start < 0) { + start = str.length() + start; // remember start is negative + } + // check length next + if (end > str.length()) { + end = str.length(); + } + // if start is greater than end, return "" + if (start > end) { + return EMPTY; + } + if (start < 0) { + start = 0; + } + if (end < 0) { + end = 0; + } + return str.substring(start, end); + } + + /** + * Gets the substring after the first occurrence of a separator. The separator is not returned. + * + *

+ * A {@code null} string input will return {@code null}. An empty ("") string input will return the empty string. + *

+ * + *

+ * If nothing is found, the empty string is returned. + *

+ * + *
+     * StringUtils.substringAfter(null, *)      = null
+     * StringUtils.substringAfter("", *)        = ""
+     * StringUtils.substringAfter("abc", 'a')   = "bc"
+     * StringUtils.substringAfter("abcba", 'b') = "cba"
+     * StringUtils.substringAfter("abc", 'c')   = ""
+     * StringUtils.substringAfter("abc", 'd')   = ""
+     * StringUtils.substringAfter(" abc", 32)   = "abc"
+     * 
+ * + * @param str the String to get a substring from, may be null. + * @param find the character (Unicode code point) to find. + * @return the substring after the first occurrence of the specified character, {@code null} if null String input. + * @since 3.11 + */ + public static String substringAfter(final String str, final int find) { + if (isEmpty(str)) { + return str; + } + final int pos = str.indexOf(find); + if (pos == INDEX_NOT_FOUND) { + return EMPTY; + } + return str.substring(pos + 1); + } + + /** + * Gets the substring after the first occurrence of a separator. The separator is not returned. + * + *

+ * A {@code null} string input will return {@code null}. An empty ("") string input will return the empty string. A {@code null} separator will return the + * empty string if the input string is not {@code null}. + *

+ * + *

+ * If nothing is found, the empty string is returned. + *

+ * + *
+     * StringUtils.substringAfter(null, *)      = null
+     * StringUtils.substringAfter("", *)        = ""
+     * StringUtils.substringAfter(*, null)      = ""
+     * StringUtils.substringAfter("abc", "a")   = "bc"
+     * StringUtils.substringAfter("abcba", "b") = "cba"
+     * StringUtils.substringAfter("abc", "c")   = ""
+     * StringUtils.substringAfter("abc", "d")   = ""
+     * StringUtils.substringAfter("abc", "")    = "abc"
+     * 
+ * + * @param str the String to get a substring from, may be null. + * @param find the String to find, may be null. + * @return the substring after the first occurrence of the specified string, {@code null} if null String input. + * @since 2.0 + */ + public static String substringAfter(final String str, final String find) { + if (isEmpty(str)) { + return str; + } + if (find == null) { + return EMPTY; + } + final int pos = str.indexOf(find); + if (pos == INDEX_NOT_FOUND) { + return EMPTY; + } + return str.substring(pos + find.length()); + } + + /** + * Gets the substring after the last occurrence of a separator. The separator is not returned. + * + *

+ * A {@code null} string input will return {@code null}. An empty ("") string input will return the empty string. + *

+ * + *

+ * If nothing is found, the empty string is returned. + *

+ * + *
+     * StringUtils.substringAfterLast(null, *)      = null
+     * StringUtils.substringAfterLast("", *)        = ""
+     * StringUtils.substringAfterLast("abc", 'a')   = "bc"
+     * StringUtils.substringAfterLast(" bc", 32)    = "bc"
+     * StringUtils.substringAfterLast("abcba", 'b') = "a"
+     * StringUtils.substringAfterLast("abc", 'c')   = ""
+     * StringUtils.substringAfterLast("a", 'a')     = ""
+     * StringUtils.substringAfterLast("a", 'z')     = ""
+     * 
+ * + * @param str the String to get a substring from, may be null. + * @param find the character (Unicode code point) to find. + * @return the substring after the last occurrence of the specified character, {@code null} if null String input. + * @since 3.11 + */ + public static String substringAfterLast(final String str, final int find) { + if (isEmpty(str)) { + return str; + } + final int pos = str.lastIndexOf(find); + if (pos == INDEX_NOT_FOUND || pos == str.length() - 1) { + return EMPTY; + } + return str.substring(pos + 1); + } + + /** + * Gets the substring after the last occurrence of a separator. The separator is not returned. + * + *

+ * A {@code null} string input will return {@code null}. An empty ("") string input will return the empty string. An empty or {@code null} separator will + * return the empty string if the input string is not {@code null}. + *

+ * + *

+ * If nothing is found, the empty string is returned. + *

+ * + *
+     * StringUtils.substringAfterLast(null, *)      = null
+     * StringUtils.substringAfterLast("", *)        = ""
+     * StringUtils.substringAfterLast(*, "")        = ""
+     * StringUtils.substringAfterLast(*, null)      = ""
+     * StringUtils.substringAfterLast("abc", "a")   = "bc"
+     * StringUtils.substringAfterLast("abcba", "b") = "a"
+     * StringUtils.substringAfterLast("abc", "c")   = ""
+     * StringUtils.substringAfterLast("a", "a")     = ""
+     * StringUtils.substringAfterLast("a", "z")     = ""
+     * 
+ * + * @param str the String to get a substring from, may be null. + * @param find the String to find, may be null. + * @return the substring after the last occurrence of the specified string, {@code null} if null String input. + * @since 2.0 + */ + public static String substringAfterLast(final String str, final String find) { + if (isEmpty(str)) { + return str; + } + if (isEmpty(find)) { + return EMPTY; + } + final int pos = str.lastIndexOf(find); + if (pos == INDEX_NOT_FOUND || pos == str.length() - find.length()) { + return EMPTY; + } + return str.substring(pos + find.length()); + } + + /** + * Gets the substring before the first occurrence of a separator. The separator is not returned. + * + *

+ * A {@code null} string input will return {@code null}. An empty ("") string input will return the empty string. + *

+ * + *

+ * If nothing is found, the string input is returned. + *

+ * + *
+     * StringUtils.substringBefore(null, *)      = null
+     * StringUtils.substringBefore("", *)        = ""
+     * StringUtils.substringBefore("abc", 'a')   = ""
+     * StringUtils.substringBefore("abcba", 'b') = "a"
+     * StringUtils.substringBefore("abc", 'c')   = "ab"
+     * StringUtils.substringBefore("abc", 'd')   = "abc"
+     * 
+ * + * @param str the String to get a substring from, may be null. + * @param find the character (Unicode code point) to find. + * @return the substring before the first occurrence of the specified character, {@code null} if null String input. + * @since 3.12.0 + */ + public static String substringBefore(final String str, final int find) { + if (isEmpty(str)) { + return str; + } + final int pos = str.indexOf(find); + if (pos == INDEX_NOT_FOUND) { + return str; + } + return str.substring(0, pos); + } + + /** + * Gets the substring before the first occurrence of a separator. The separator is not returned. + * + *

+ * A {@code null} string input will return {@code null}. An empty ("") string input will return the empty string. A {@code null} separator will return the + * input string. + *

+ * + *

+ * If nothing is found, the string input is returned. + *

+ * + *
+     * StringUtils.substringBefore(null, *)      = null
+     * StringUtils.substringBefore("", *)        = ""
+     * StringUtils.substringBefore("abc", "a")   = ""
+     * StringUtils.substringBefore("abcba", "b") = "a"
+     * StringUtils.substringBefore("abc", "c")   = "ab"
+     * StringUtils.substringBefore("abc", "d")   = "abc"
+     * StringUtils.substringBefore("abc", "")    = ""
+     * StringUtils.substringBefore("abc", null)  = "abc"
+     * 
+ * + * @param str the String to get a substring from, may be null. + * @param find the String to find, may be null. + * @return the substring before the first occurrence of the specified string, {@code null} if null String input. + * @since 2.0 + */ + public static String substringBefore(final String str, final String find) { + if (isEmpty(str) || find == null) { + return str; + } + if (find.isEmpty()) { + return EMPTY; + } + final int pos = str.indexOf(find); + if (pos == INDEX_NOT_FOUND) { + return str; + } + return str.substring(0, pos); + } + + /** + * Gets the substring before the last occurrence of a separator. The separator is not returned. + * + *

+ * A {@code null} string input will return {@code null}. An empty ("") string input will return the empty string. An empty or {@code null} separator will + * return the input string. + *

+ * + *

+ * If nothing is found, the string input is returned. + *

+ * + *
+     * StringUtils.substringBeforeLast(null, *)      = null
+     * StringUtils.substringBeforeLast("", *)        = ""
+     * StringUtils.substringBeforeLast("abcba", "b") = "abc"
+     * StringUtils.substringBeforeLast("abc", "c")   = "ab"
+     * StringUtils.substringBeforeLast("a", "a")     = ""
+     * StringUtils.substringBeforeLast("a", "z")     = "a"
+     * StringUtils.substringBeforeLast("a", null)    = "a"
+     * StringUtils.substringBeforeLast("a", "")      = "a"
+     * 
+ * + * @param str the String to get a substring from, may be null. + * @param find the String to find, may be null. + * @return the substring before the last occurrence of the specified string, {@code null} if null String input. + * @since 2.0 + */ + public static String substringBeforeLast(final String str, final String find) { + if (isEmpty(str) || isEmpty(find)) { + return str; + } + final int pos = str.lastIndexOf(find); + if (pos == INDEX_NOT_FOUND) { + return str; + } + return str.substring(0, pos); + } + + /** + * Gets the String that is nested in between two instances of the same String. + * + *

+ * A {@code null} input String returns {@code null}. A {@code null} tag returns {@code null}. + *

+ * + *
+     * StringUtils.substringBetween(null, *)            = null
+     * StringUtils.substringBetween("", "")             = ""
+     * StringUtils.substringBetween("", "tag")          = null
+     * StringUtils.substringBetween("tagabctag", null)  = null
+     * StringUtils.substringBetween("tagabctag", "")    = ""
+     * StringUtils.substringBetween("tagabctag", "tag") = "abc"
+     * 
+ * + * @param str the String containing the substring, may be null. + * @param tag the String before and after the substring, may be null. + * @return the substring, {@code null} if no match. + * @since 2.0 + */ + public static String substringBetween(final String str, final String tag) { + return substringBetween(str, tag, tag); + } + + /** + * Gets the String that is nested in between two Strings. Only the first match is returned. + * + *

+ * A {@code null} input String returns {@code null}. A {@code null} open/close returns {@code null} (no match). An empty ("") open and close returns an + * empty string. + *

+ * + *
+     * StringUtils.substringBetween("wx[b]yz", "[", "]") = "b"
+     * StringUtils.substringBetween(null, *, *)          = null
+     * StringUtils.substringBetween(*, null, *)          = null
+     * StringUtils.substringBetween(*, *, null)          = null
+     * StringUtils.substringBetween("", "", "")          = ""
+     * StringUtils.substringBetween("", "", "]")         = null
+     * StringUtils.substringBetween("", "[", "]")        = null
+     * StringUtils.substringBetween("yabcz", "", "")     = ""
+     * StringUtils.substringBetween("yabcz", "y", "z")   = "abc"
+     * StringUtils.substringBetween("yabczyabcz", "y", "z")   = "abc"
+     * 
+ * + * @param str the String containing the substring, may be null. + * @param open the String before the substring, may be null. + * @param close the String after the substring, may be null. + * @return the substring, {@code null} if no match. + * @since 2.0 + */ + public static String substringBetween(final String str, final String open, final String close) { + if (!ObjectUtils.allNotNull(str, open, close)) { + return null; + } + final int start = str.indexOf(open); + if (start != INDEX_NOT_FOUND) { + final int end = str.indexOf(close, start + open.length()); + if (end != INDEX_NOT_FOUND) { + return str.substring(start + open.length(), end); + } + } + return null; + } + + /** + * Searches a String for substrings delimited by a start and end tag, returning all matching substrings in an array. + * + *

+ * A {@code null} input String returns {@code null}. A {@code null} open/close returns {@code null} (no match). An empty ("") open/close returns + * {@code null} (no match). + *

+ * + *
+     * StringUtils.substringsBetween("[a][b][c]", "[", "]") = ["a","b","c"]
+     * StringUtils.substringsBetween(null, *, *)            = null
+     * StringUtils.substringsBetween(*, null, *)            = null
+     * StringUtils.substringsBetween(*, *, null)            = null
+     * StringUtils.substringsBetween("", "[", "]")          = []
+     * 
+ * + * @param str the String containing the substrings, null returns null, empty returns empty. + * @param open the String identifying the start of the substring, empty returns null. + * @param close the String identifying the end of the substring, empty returns null. + * @return a String Array of substrings, or {@code null} if no match. + * @since 2.3 + */ + public static String[] substringsBetween(final String str, final String open, final String close) { + if (str == null || isEmpty(open) || isEmpty(close)) { + return null; + } + final int strLen = str.length(); + if (strLen == 0) { + return ArrayUtils.EMPTY_STRING_ARRAY; + } + final int closeLen = close.length(); + final int openLen = open.length(); + final List list = new ArrayList<>(); + int pos = 0; + while (pos < strLen - closeLen) { + int start = str.indexOf(open, pos); + if (start < 0) { + break; + } + start += openLen; + final int end = str.indexOf(close, start); + if (end < 0) { + break; + } + list.add(str.substring(start, end)); + pos = end + closeLen; + } + if (list.isEmpty()) { + return null; + } + return list.toArray(ArrayUtils.EMPTY_STRING_ARRAY); + } + + /** + * Swaps the case of a String changing upper and title case to lower case, and lower case to upper case. + * + *
    + *
  • Upper case character converts to Lower case
  • + *
  • Title case character converts to Lower case
  • + *
  • Lower case character converts to Upper case
  • + *
+ * + *

+ * For a word based algorithm, see {@link org.apache.commons.text.WordUtils#swapCase(String)}. A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.swapCase(null)                 = null
+     * StringUtils.swapCase("")                   = ""
+     * StringUtils.swapCase("The dog has a BONE") = "tHE DOG HAS A bone"
+     * 
+ * + *

+ * NOTE: This method changed in Lang version 2.0. It no longer performs a word based algorithm. If you only use ASCII, you will notice no change. That + * functionality is available in org.apache.commons.lang3.text.WordUtils. + *

+ * + * @param str the String to swap case, may be null. + * @return the changed String, {@code null} if null String input. + */ + public static String swapCase(final String str) { + if (isEmpty(str)) { + return str; + } + final int strLen = str.length(); + final int[] newCodePoints = new int[strLen]; // cannot be longer than the char array + int outOffset = 0; + for (int i = 0; i < strLen;) { + final int oldCodepoint = str.codePointAt(i); + final int newCodePoint; + if (Character.isUpperCase(oldCodepoint) || Character.isTitleCase(oldCodepoint)) { + newCodePoint = Character.toLowerCase(oldCodepoint); + } else if (Character.isLowerCase(oldCodepoint)) { + newCodePoint = Character.toUpperCase(oldCodepoint); + } else { + newCodePoint = oldCodepoint; + } + newCodePoints[outOffset++] = newCodePoint; + i += Character.charCount(newCodePoint); + } + return new String(newCodePoints, 0, outOffset); + } + + /** + * Converts a {@link CharSequence} into an array of code points. + * + *

+ * Valid pairs of surrogate code units will be converted into a single supplementary code point. Isolated surrogate code units (i.e. a high surrogate not + * followed by a low surrogate or a low surrogate not preceded by a high surrogate) will be returned as-is. + *

+ * + *
+     * StringUtils.toCodePoints(null)   =  null
+     * StringUtils.toCodePoints("")     =  []  // empty array
+     * 
+ * + * @param cs the character sequence to convert. + * @return an array of code points. + * @since 3.6 + */ + public static int[] toCodePoints(final CharSequence cs) { + if (cs == null) { + return null; + } + if (cs.length() == 0) { + return ArrayUtils.EMPTY_INT_ARRAY; + } + return cs.toString().codePoints().toArray(); + } + + /** + * Converts a {@code byte[]} to a String using the specified character encoding. + * + * @param bytes the byte array to read from. + * @param charset the encoding to use, if null then use the platform default. + * @return a new String. + * @throws NullPointerException if {@code bytes} is null + * @since 3.2 + * @since 3.3 No longer throws {@link UnsupportedEncodingException}. + */ + public static String toEncodedString(final byte[] bytes, final Charset charset) { + return new String(bytes, Charsets.toCharset(charset)); + } + + /** + * Converts the given source String as a lower-case using the {@link Locale#ROOT} locale in a null-safe manner. + * + * @param source A source String or null. + * @return the given source String as a lower-case using the {@link Locale#ROOT} locale or null. + * @since 3.10 + */ + public static String toRootLowerCase(final String source) { + return source == null ? null : source.toLowerCase(Locale.ROOT); + } + + /** + * Converts the given source String as an upper-case using the {@link Locale#ROOT} locale in a null-safe manner. + * + * @param source A source String or null. + * @return the given source String as an upper-case using the {@link Locale#ROOT} locale or null. + * @since 3.10 + */ + public static String toRootUpperCase(final String source) { + return source == null ? null : source.toUpperCase(Locale.ROOT); + } + + /** + * Converts a {@code byte[]} to a String using the specified character encoding. + * + * @param bytes the byte array to read from. + * @param charsetName the encoding to use, if null then use the platform default. + * @return a new String. + * @throws NullPointerException if the input is null. + * @since 3.1 + * @deprecated Use {@link StringUtils#toEncodedString(byte[], Charset)} instead of String constants in your code. + */ + @Deprecated + public static String toString(final byte[] bytes, final String charsetName) { + return new String(bytes, Charsets.toCharset(charsetName)); + } + + /** + * Removes control characters (char <= 32) from both ends of this String, handling {@code null} by returning {@code null}. + * + *

+ * The String is trimmed using {@link String#trim()}. Trim removes start and end characters <= 32. To strip whitespace use {@link #strip(String)}. + *

+ * + *

+ * To trim your choice of characters, use the {@link #strip(String, String)} methods. + *

+ * + *
+     * StringUtils.trim(null)          = null
+     * StringUtils.trim("")            = ""
+     * StringUtils.trim("     ")       = ""
+     * StringUtils.trim("abc")         = "abc"
+     * StringUtils.trim("    abc    ") = "abc"
+     * 
+ * + * @param str the String to be trimmed, may be null. + * @return the trimmed string, {@code null} if null String input. + */ + public static String trim(final String str) { + return str == null ? null : str.trim(); + } + + /** + * Removes control characters (char <= 32) from both ends of this String returning an empty String ("") if the String is empty ("") after the trim or if + * it is {@code null}. + * + *

+ * The String is trimmed using {@link String#trim()}. Trim removes start and end characters <= 32. To strip whitespace use {@link #stripToEmpty(String)}. + *

+ * + *
+     * StringUtils.trimToEmpty(null)          = ""
+     * StringUtils.trimToEmpty("")            = ""
+     * StringUtils.trimToEmpty("     ")       = ""
+     * StringUtils.trimToEmpty("abc")         = "abc"
+     * StringUtils.trimToEmpty("    abc    ") = "abc"
+     * 
+ * + * @param str the String to be trimmed, may be null. + * @return the trimmed String, or an empty String if {@code null} input. + * @since 2.0 + */ + public static String trimToEmpty(final String str) { + return str == null ? EMPTY : str.trim(); + } + + /** + * Removes control characters (char <= 32) from both ends of this String returning {@code null} if the String is empty ("") after the trim or if it is + * {@code null}. + * + *

+ * The String is trimmed using {@link String#trim()}. Trim removes start and end characters <= 32. To strip whitespace use {@link #stripToNull(String)}. + *

+ * + *
+     * StringUtils.trimToNull(null)          = null
+     * StringUtils.trimToNull("")            = null
+     * StringUtils.trimToNull("     ")       = null
+     * StringUtils.trimToNull("abc")         = "abc"
+     * StringUtils.trimToNull("    abc    ") = "abc"
+     * 
+ * + * @param str the String to be trimmed, may be null. + * @return the trimmed String, {@code null} if only chars <= 32, empty or null String input. + * @since 2.0 + */ + public static String trimToNull(final String str) { + final String ts = trim(str); + return isEmpty(ts) ? null : ts; + } + + /** + * Truncates a String. This will turn "Now is the time for all good men" into "Now is the time for". + * + *

+ * Specifically: + *

+ *
    + *
  • If {@code str} is less than {@code maxWidth} characters long, return it.
  • + *
  • Else truncate it to {@code substring(str, 0, maxWidth)}.
  • + *
  • If {@code maxWidth} is less than {@code 0}, throw an {@link IllegalArgumentException}.
  • + *
  • In no case will it return a String of length greater than {@code maxWidth}.
  • + *
+ * + *
+     * StringUtils.truncate(null, 0)       = null
+     * StringUtils.truncate(null, 2)       = null
+     * StringUtils.truncate("", 4)         = ""
+     * StringUtils.truncate("abcdefg", 4)  = "abcd"
+     * StringUtils.truncate("abcdefg", 6)  = "abcdef"
+     * StringUtils.truncate("abcdefg", 7)  = "abcdefg"
+     * StringUtils.truncate("abcdefg", 8)  = "abcdefg"
+     * StringUtils.truncate("abcdefg", -1) = throws an IllegalArgumentException
+     * 
+ * + * @param str the String to truncate, may be null. + * @param maxWidth maximum length of result String, must be non-negative. + * @return truncated String, {@code null} if null String input. + * @throws IllegalArgumentException If {@code maxWidth} is less than {@code 0}. + * @since 3.5 + */ + public static String truncate(final String str, final int maxWidth) { + return truncate(str, 0, maxWidth); + } + + /** + * Truncates a String. This will turn "Now is the time for all good men" into "is the time for all". + * + *

+ * Works like {@code truncate(String, int)}, but allows you to specify a "left edge" offset. + *

+ * + *

+ * Specifically: + *

+ *
    + *
  • If {@code str} is less than {@code maxWidth} characters long, return it.
  • + *
  • Else truncate it to {@code substring(str, offset, maxWidth)}.
  • + *
  • If {@code maxWidth} is less than {@code 0}, throw an {@link IllegalArgumentException}.
  • + *
  • If {@code offset} is less than {@code 0}, throw an {@link IllegalArgumentException}.
  • + *
  • In no case will it return a String of length greater than {@code maxWidth}.
  • + *
+ * + *
+     * StringUtils.truncate(null, 0, 0) = null
+     * StringUtils.truncate(null, 2, 4) = null
+     * StringUtils.truncate("", 0, 10) = ""
+     * StringUtils.truncate("", 2, 10) = ""
+     * StringUtils.truncate("abcdefghij", 0, 3) = "abc"
+     * StringUtils.truncate("abcdefghij", 5, 6) = "fghij"
+     * StringUtils.truncate("raspberry peach", 10, 15) = "peach"
+     * StringUtils.truncate("abcdefghijklmno", 0, 10) = "abcdefghij"
+     * StringUtils.truncate("abcdefghijklmno", -1, 10) = throws an IllegalArgumentException
+     * StringUtils.truncate("abcdefghijklmno", Integer.MIN_VALUE, 10) = throws an IllegalArgumentException
+     * StringUtils.truncate("abcdefghijklmno", Integer.MIN_VALUE, Integer.MAX_VALUE) = throws an IllegalArgumentException
+     * StringUtils.truncate("abcdefghijklmno", 0, Integer.MAX_VALUE) = "abcdefghijklmno"
+     * StringUtils.truncate("abcdefghijklmno", 1, 10) = "bcdefghijk"
+     * StringUtils.truncate("abcdefghijklmno", 2, 10) = "cdefghijkl"
+     * StringUtils.truncate("abcdefghijklmno", 3, 10) = "defghijklm"
+     * StringUtils.truncate("abcdefghijklmno", 4, 10) = "efghijklmn"
+     * StringUtils.truncate("abcdefghijklmno", 5, 10) = "fghijklmno"
+     * StringUtils.truncate("abcdefghijklmno", 5, 5) = "fghij"
+     * StringUtils.truncate("abcdefghijklmno", 5, 3) = "fgh"
+     * StringUtils.truncate("abcdefghijklmno", 10, 3) = "klm"
+     * StringUtils.truncate("abcdefghijklmno", 10, Integer.MAX_VALUE) = "klmno"
+     * StringUtils.truncate("abcdefghijklmno", 13, 1) = "n"
+     * StringUtils.truncate("abcdefghijklmno", 13, Integer.MAX_VALUE) = "no"
+     * StringUtils.truncate("abcdefghijklmno", 14, 1) = "o"
+     * StringUtils.truncate("abcdefghijklmno", 14, Integer.MAX_VALUE) = "o"
+     * StringUtils.truncate("abcdefghijklmno", 15, 1) = ""
+     * StringUtils.truncate("abcdefghijklmno", 15, Integer.MAX_VALUE) = ""
+     * StringUtils.truncate("abcdefghijklmno", Integer.MAX_VALUE, Integer.MAX_VALUE) = ""
+     * StringUtils.truncate("abcdefghij", 3, -1) = throws an IllegalArgumentException
+     * StringUtils.truncate("abcdefghij", -2, 4) = throws an IllegalArgumentException
+     * 
+ * + * @param str the String to truncate, may be null. + * @param offset left edge of source String. + * @param maxWidth maximum length of result String, must be non-negative. + * @return truncated String, {@code null} if null String input. + * @throws IllegalArgumentException If {@code offset} or {@code maxWidth} is less than {@code 0}. + * @since 3.5 + */ + public static String truncate(final String str, final int offset, final int maxWidth) { + if (offset < 0) { + throw new IllegalArgumentException("offset cannot be negative"); + } + if (maxWidth < 0) { + throw new IllegalArgumentException("maxWidth cannot be negative"); + } + if (str == null) { + return null; + } + final int len = str.length(); + final int start = Math.min(offset, len); + final int end = offset > len - maxWidth ? len : offset + maxWidth; + return str.substring(start, Math.min(end, len)); + } + + /** + * Uncapitalizes a String, changing the first character to lower case as per {@link Character#toLowerCase(int)}. No other characters are changed. + * + *

+ * For a word based algorithm, see {@link org.apache.commons.text.WordUtils#uncapitalize(String)}. A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.uncapitalize(null)  = null
+     * StringUtils.uncapitalize("")    = ""
+     * StringUtils.uncapitalize("cat") = "cat"
+     * StringUtils.uncapitalize("Cat") = "cat"
+     * StringUtils.uncapitalize("CAT") = "cAT"
+     * 
+ * + * @param str the String to uncapitalize, may be null. + * @return the uncapitalized String, {@code null} if null String input. + * @see org.apache.commons.text.WordUtils#uncapitalize(String) + * @see #capitalize(String) + * @since 2.0 + */ + public static String uncapitalize(final String str) { + final int strLen = length(str); + if (strLen == 0) { + return str; + } + final int firstCodePoint = str.codePointAt(0); + final int newCodePoint = Character.toLowerCase(firstCodePoint); + if (firstCodePoint == newCodePoint) { + // already uncapitalized + return str; + } + final int[] newCodePoints = str.codePoints().toArray(); + newCodePoints[0] = newCodePoint; // copy the first code point + return new String(newCodePoints, 0, newCodePoints.length); + } + + /** + * Unwraps a given string from a character. + * + *
+     * StringUtils.unwrap(null, null)         = null
+     * StringUtils.unwrap(null, '\0')         = null
+     * StringUtils.unwrap(null, '1')          = null
+     * StringUtils.unwrap("a", 'a')           = "a"
+     * StringUtils.unwrap("aa", 'a')           = ""
+     * StringUtils.unwrap("\'abc\'", '\'')    = "abc"
+     * StringUtils.unwrap("AABabcBAA", 'A')   = "ABabcBA"
+     * StringUtils.unwrap("A", '#')           = "A"
+     * StringUtils.unwrap("#A", '#')          = "#A"
+     * StringUtils.unwrap("A#", '#')          = "A#"
+     * 
+ * + * @param str the String to be unwrapped, can be null. + * @param wrapChar the character used to unwrap. + * @return unwrapped String or the original string if it is not quoted properly with the wrapChar. + * @since 3.6 + */ + public static String unwrap(final String str, final char wrapChar) { + if (isEmpty(str) || wrapChar == CharUtils.NUL || str.length() == 1) { + return str; + } + if (str.charAt(0) == wrapChar && str.charAt(str.length() - 1) == wrapChar) { + final int startIndex = 0; + final int endIndex = str.length() - 1; + return str.substring(startIndex + 1, endIndex); + } + return str; + } + + /** + * Unwraps a given string from another string. + * + *
+     * StringUtils.unwrap(null, null)         = null
+     * StringUtils.unwrap(null, "")           = null
+     * StringUtils.unwrap(null, "1")          = null
+     * StringUtils.unwrap("a", "a")           = "a"
+     * StringUtils.unwrap("aa", "a")          = ""
+     * StringUtils.unwrap("\'abc\'", "\'")    = "abc"
+     * StringUtils.unwrap("\"abc\"", "\"")    = "abc"
+     * StringUtils.unwrap("AABabcBAA", "AA")  = "BabcB"
+     * StringUtils.unwrap("A", "#")           = "A"
+     * StringUtils.unwrap("#A", "#")          = "#A"
+     * StringUtils.unwrap("A#", "#")          = "A#"
+     * 
+ * + * @param str the String to be unwrapped, can be null. + * @param wrapToken the String used to unwrap. + * @return unwrapped String or the original string if it is not quoted properly with the wrapToken. + * @since 3.6 + */ + public static String unwrap(final String str, final String wrapToken) { + if (isEmpty(str) || isEmpty(wrapToken) || str.length() < 2 * wrapToken.length()) { + return str; + } + if (Strings.CS.startsWith(str, wrapToken) && Strings.CS.endsWith(str, wrapToken)) { + return str.substring(wrapToken.length(), str.lastIndexOf(wrapToken)); + } + return str; + } + + /** + * Converts a String to upper case as per {@link String#toUpperCase()}. + * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.upperCase(null)  = null
+     * StringUtils.upperCase("")    = ""
+     * StringUtils.upperCase("aBc") = "ABC"
+     * 
+ * + *

+ * Note: As described in the documentation for {@link String#toUpperCase()}, the result of this method is affected by the current locale. + * For platform-independent case transformations, the method {@link #upperCase(String, Locale)} should be used with a specific locale (e.g. + * {@link Locale#ENGLISH}). + *

+ * + * @param str the String to upper case, may be null. + * @return the upper-cased String, {@code null} if null String input. + */ + public static String upperCase(final String str) { + if (str == null) { + return null; + } + return str.toUpperCase(); + } + + /** + * Converts a String to upper case as per {@link String#toUpperCase(Locale)}. + * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.upperCase(null, Locale.ENGLISH)  = null
+     * StringUtils.upperCase("", Locale.ENGLISH)    = ""
+     * StringUtils.upperCase("aBc", Locale.ENGLISH) = "ABC"
+     * 
+ * + * @param str the String to upper case, may be null. + * @param locale the locale that defines the case transformation rules, must not be null. + * @return the upper-cased String, {@code null} if null String input. + * @since 2.5 + */ + public static String upperCase(final String str, final Locale locale) { + if (str == null) { + return null; + } + return str.toUpperCase(LocaleUtils.toLocale(locale)); + } + + /** + * Returns the string representation of the {@code char} array or null. + * + * @param value the character array. + * @return a String or null. + * @see String#valueOf(char[]) + * @since 3.9 + */ + public static String valueOf(final char[] value) { + return value == null ? null : String.valueOf(value); + } + + /** + * Wraps a string with a char. + * + *
+     * StringUtils.wrap(null, *)        = null
+     * StringUtils.wrap("", *)          = ""
+     * StringUtils.wrap("ab", '\0')     = "ab"
+     * StringUtils.wrap("ab", 'x')      = "xabx"
+     * StringUtils.wrap("ab", '\'')     = "'ab'"
+     * StringUtils.wrap("\"ab\"", '\"') = "\"\"ab\"\""
+     * 
+ * + * @param str the string to be wrapped, may be {@code null}. + * @param wrapWith the char that will wrap {@code str}. + * @return the wrapped string, or {@code null} if {@code str == null}. + * @since 3.4 + */ + public static String wrap(final String str, final char wrapWith) { + if (isEmpty(str) || wrapWith == CharUtils.NUL) { + return str; + } + return wrapWith + str + wrapWith; + } + + /** + * Wraps a String with another String. + * + *

+ * A {@code null} input String returns {@code null}. + *

+ * + *
+     * StringUtils.wrap(null, *)         = null
+     * StringUtils.wrap("", *)           = ""
+     * StringUtils.wrap("ab", null)      = "ab"
+     * StringUtils.wrap("ab", "x")       = "xabx"
+     * StringUtils.wrap("ab", "\"")      = "\"ab\""
+     * StringUtils.wrap("\"ab\"", "\"")  = "\"\"ab\"\""
+     * StringUtils.wrap("ab", "'")       = "'ab'"
+     * StringUtils.wrap("'abcd'", "'")   = "''abcd''"
+     * StringUtils.wrap("\"abcd\"", "'") = "'\"abcd\"'"
+     * StringUtils.wrap("'abcd'", "\"")  = "\"'abcd'\""
+     * 
+ * + * @param str the String to be wrapper, may be null. + * @param wrapWith the String that will wrap str. + * @return wrapped String, {@code null} if null String input. + * @since 3.4 + */ + public static String wrap(final String str, final String wrapWith) { + if (isEmpty(str) || isEmpty(wrapWith)) { + return str; + } + return wrapWith.concat(str).concat(wrapWith); + } + + /** + * Wraps a string with a char if that char is missing from the start or end of the given string. + * + *

+ * A new {@link String} will not be created if {@code str} is already wrapped. + *

+ * + *
+     * StringUtils.wrapIfMissing(null, *)        = null
+     * StringUtils.wrapIfMissing("", *)          = ""
+     * StringUtils.wrapIfMissing("ab", '\0')     = "ab"
+     * StringUtils.wrapIfMissing("ab", 'x')      = "xabx"
+     * StringUtils.wrapIfMissing("ab", '\'')     = "'ab'"
+     * StringUtils.wrapIfMissing("\"ab\"", '\"') = "\"ab\""
+     * StringUtils.wrapIfMissing("/", '/')  = "/"
+     * StringUtils.wrapIfMissing("a/b/c", '/')  = "/a/b/c/"
+     * StringUtils.wrapIfMissing("/a/b/c", '/')  = "/a/b/c/"
+     * StringUtils.wrapIfMissing("a/b/c/", '/')  = "/a/b/c/"
+     * 
+ * + * @param str the string to be wrapped, may be {@code null}. + * @param wrapWith the char that will wrap {@code str}. + * @return the wrapped string, or {@code null} if {@code str == null}. + * @since 3.5 + */ + public static String wrapIfMissing(final String str, final char wrapWith) { + if (isEmpty(str) || wrapWith == CharUtils.NUL) { + return str; + } + final boolean wrapStart = str.charAt(0) != wrapWith; + final boolean wrapEnd = str.charAt(str.length() - 1) != wrapWith; + if (!wrapStart && !wrapEnd) { + return str; + } + final StringBuilder builder = new StringBuilder(str.length() + 2); + if (wrapStart) { + builder.append(wrapWith); + } + builder.append(str); + if (wrapEnd) { + builder.append(wrapWith); + } + return builder.toString(); + } + + /** + * Wraps a string with a string if that string is missing from the start or end of the given string. + * + *

+ * A new {@link String} will not be created if {@code str} is already wrapped. + *

+ * + *
+     * StringUtils.wrapIfMissing(null, *)         = null
+     * StringUtils.wrapIfMissing("", *)           = ""
+     * StringUtils.wrapIfMissing("ab", null)      = "ab"
+     * StringUtils.wrapIfMissing("ab", "x")       = "xabx"
+     * StringUtils.wrapIfMissing("ab", "\"")      = "\"ab\""
+     * StringUtils.wrapIfMissing("\"ab\"", "\"")  = "\"ab\""
+     * StringUtils.wrapIfMissing("ab", "'")       = "'ab'"
+     * StringUtils.wrapIfMissing("'abcd'", "'")   = "'abcd'"
+     * StringUtils.wrapIfMissing("\"abcd\"", "'") = "'\"abcd\"'"
+     * StringUtils.wrapIfMissing("'abcd'", "\"")  = "\"'abcd'\""
+     * StringUtils.wrapIfMissing("/", "/")  = "/"
+     * StringUtils.wrapIfMissing("a/b/c", "/")  = "/a/b/c/"
+     * StringUtils.wrapIfMissing("/a/b/c", "/")  = "/a/b/c/"
+     * StringUtils.wrapIfMissing("a/b/c/", "/")  = "/a/b/c/"
+     * 
+ * + * @param str the string to be wrapped, may be {@code null}. + * @param wrapWith the string that will wrap {@code str}. + * @return the wrapped string, or {@code null} if {@code str == null}. + * @since 3.5 + */ + public static String wrapIfMissing(final String str, final String wrapWith) { + if (isEmpty(str) || isEmpty(wrapWith)) { + return str; + } + final boolean wrapStart = !str.startsWith(wrapWith); + final boolean wrapEnd = !str.endsWith(wrapWith); + if (!wrapStart && !wrapEnd) { + return str; + } + final StringBuilder builder = new StringBuilder(str.length() + wrapWith.length() + wrapWith.length()); + if (wrapStart) { + builder.append(wrapWith); + } + builder.append(str); + if (wrapEnd) { + builder.append(wrapWith); + } + return builder.toString(); + } + + /** + * {@link StringUtils} instances should NOT be constructed in standard programming. Instead, the class should be used as {@code StringUtils.trim(" foo ");}. + * + *

+ * This constructor is public to permit tools that require a JavaBean instance to operate. + *

+ * + * @deprecated TODO Make private in 4.0. + */ + @Deprecated + public StringUtils() { + // empty + } + +}