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p62xrbca7/java/nio/IntBuffer.java

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/*
* Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
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*/
// -- This file was mechanically generated: Do not edit! -- //
package java.nio;
/**
* An int buffer.
*
* <p> This class defines four categories of operations upon
* int buffers:
*
* <ul>
*
* <li><p> Absolute and relative {@link #get() <i>get</i>} and
* {@link #put(int) <i>put</i>} methods that read and write
* single ints; </p></li>
*
* <li><p> Relative {@link #get(int[]) <i>bulk get</i>}
* methods that transfer contiguous sequences of ints from this buffer
* into an array; and</p></li>
*
* <li><p> Relative {@link #put(int[]) <i>bulk put</i>}
* methods that transfer contiguous sequences of ints from an
* int array or some other int
* buffer into this buffer;&#32;and </p></li>
*
*
* <li><p> Methods for {@link #compact compacting}, {@link
* #duplicate duplicating}, and {@link #slice slicing}
* an int buffer. </p></li>
*
* </ul>
*
* <p> Int buffers can be created either by {@link #allocate
* <i>allocation</i>}, which allocates space for the buffer's
*
*
* content, by {@link #wrap(int[]) <i>wrapping</i>} an existing
* int array into a buffer, or by creating a
* <a href="ByteBuffer.html#views"><i>view</i></a> of an existing byte buffer.
*
*
*
*
* <p> Like a byte buffer, an int buffer is either <a
* href="ByteBuffer.html#direct"><i>direct</i> or <i>non-direct</i></a>. A
* int buffer created via the <tt>wrap</tt> methods of this class will
* be non-direct. An int buffer created as a view of a byte buffer will
* be direct if, and only if, the byte buffer itself is direct. Whether or not
* an int buffer is direct may be determined by invoking the {@link
* #isDirect isDirect} method. </p>
*
*
*
*
* <p> Methods in this class that do not otherwise have a value to return are
* specified to return the buffer upon which they are invoked. This allows
* method invocations to be chained.
*
*
*
* @author Mark Reinhold
* @author JSR-51 Expert Group
* @since 1.4
*/
public abstract class IntBuffer
extends Buffer
implements Comparable<IntBuffer>
{
// These fields are declared here rather than in Heap-X-Buffer in order to
// reduce the number of virtual method invocations needed to access these
// values, which is especially costly when coding small buffers.
//
final int[] hb; // Non-null only for heap buffers
final int offset;
boolean isReadOnly; // Valid only for heap buffers
// Creates a new buffer with the given mark, position, limit, capacity,
// backing array, and array offset
//
IntBuffer(int mark, int pos, int lim, int cap, // package-private
int[] hb, int offset)
{
super(mark, pos, lim, cap);
this.hb = hb;
this.offset = offset;
}
// Creates a new buffer with the given mark, position, limit, and capacity
//
IntBuffer(int mark, int pos, int lim, int cap) { // package-private
this(mark, pos, lim, cap, null, 0);
}
/**
* Allocates a new int buffer.
*
* <p> The new buffer's position will be zero, its limit will be its
* capacity, its mark will be undefined, and each of its elements will be
* initialized to zero. It will have a {@link #array backing array},
* and its {@link #arrayOffset array offset} will be zero.
*
* @param capacity
* The new buffer's capacity, in ints
*
* @return The new int buffer
*
* @throws IllegalArgumentException
* If the <tt>capacity</tt> is a negative integer
*/
public static IntBuffer allocate(int capacity) {
if (capacity < 0)
throw new IllegalArgumentException();
return new HeapIntBuffer(capacity, capacity);
}
/**
* Wraps an int array into a buffer.
*
* <p> The new buffer will be backed by the given int array;
* that is, modifications to the buffer will cause the array to be modified
* and vice versa. The new buffer's capacity will be
* <tt>array.length</tt>, its position will be <tt>offset</tt>, its limit
* will be <tt>offset + length</tt>, and its mark will be undefined. Its
* {@link #array backing array} will be the given array, and
* its {@link #arrayOffset array offset} will be zero. </p>
*
* @param array
* The array that will back the new buffer
*
* @param offset
* The offset of the subarray to be used; must be non-negative and
* no larger than <tt>array.length</tt>. The new buffer's position
* will be set to this value.
*
* @param length
* The length of the subarray to be used;
* must be non-negative and no larger than
* <tt>array.length - offset</tt>.
* The new buffer's limit will be set to <tt>offset + length</tt>.
*
* @return The new int buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the <tt>offset</tt> and <tt>length</tt>
* parameters do not hold
*/
public static IntBuffer wrap(int[] array,
int offset, int length)
{
try {
return new HeapIntBuffer(array, offset, length);
} catch (IllegalArgumentException x) {
throw new IndexOutOfBoundsException();
}
}
/**
* Wraps an int array into a buffer.
*
* <p> The new buffer will be backed by the given int array;
* that is, modifications to the buffer will cause the array to be modified
* and vice versa. The new buffer's capacity and limit will be
* <tt>array.length</tt>, its position will be zero, and its mark will be
* undefined. Its {@link #array backing array} will be the
* given array, and its {@link #arrayOffset array offset>} will
* be zero. </p>
*
* @param array
* The array that will back this buffer
*
* @return The new int buffer
*/
public static IntBuffer wrap(int[] array) {
return wrap(array, 0, array.length);
}
/**
* Creates a new int buffer whose content is a shared subsequence of
* this buffer's content.
*
* <p> The content of the new buffer will start at this buffer's current
* position. Changes to this buffer's content will be visible in the new
* buffer, and vice versa; the two buffers' position, limit, and mark
* values will be independent.
*
* <p> The new buffer's position will be zero, its capacity and its limit
* will be the number of ints remaining in this buffer, and its mark
* will be undefined. The new buffer will be direct if, and only if, this
* buffer is direct, and it will be read-only if, and only if, this buffer
* is read-only. </p>
*
* @return The new int buffer
*/
public abstract IntBuffer slice();
/**
* Creates a new int buffer that shares this buffer's content.
*
* <p> The content of the new buffer will be that of this buffer. Changes
* to this buffer's content will be visible in the new buffer, and vice
* versa; the two buffers' position, limit, and mark values will be
* independent.
*
* <p> The new buffer's capacity, limit, position, and mark values will be
* identical to those of this buffer. The new buffer will be direct if,
* and only if, this buffer is direct, and it will be read-only if, and
* only if, this buffer is read-only. </p>
*
* @return The new int buffer
*/
public abstract IntBuffer duplicate();
/**
* Creates a new, read-only int buffer that shares this buffer's
* content.
*
* <p> The content of the new buffer will be that of this buffer. Changes
* to this buffer's content will be visible in the new buffer; the new
* buffer itself, however, will be read-only and will not allow the shared
* content to be modified. The two buffers' position, limit, and mark
* values will be independent.
*
* <p> The new buffer's capacity, limit, position, and mark values will be
* identical to those of this buffer.
*
* <p> If this buffer is itself read-only then this method behaves in
* exactly the same way as the {@link #duplicate duplicate} method. </p>
*
* @return The new, read-only int buffer
*/
public abstract IntBuffer asReadOnlyBuffer();
// -- Singleton get/put methods --
/**
* Relative <i>get</i> method. Reads the int at this buffer's
* current position, and then increments the position.
*
* @return The int at the buffer's current position
*
* @throws BufferUnderflowException
* If the buffer's current position is not smaller than its limit
*/
public abstract int get();
/**
* Relative <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
*
* <p> Writes the given int into this buffer at the current
* position, and then increments the position. </p>
*
* @param i
* The int to be written
*
* @return This buffer
*
* @throws BufferOverflowException
* If this buffer's current position is not smaller than its limit
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract IntBuffer put(int i);
/**
* Absolute <i>get</i> method. Reads the int at the given
* index.
*
* @param index
* The index from which the int will be read
*
* @return The int at the given index
*
* @throws IndexOutOfBoundsException
* If <tt>index</tt> is negative
* or not smaller than the buffer's limit
*/
public abstract int get(int index);
/**
* Absolute <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
*
* <p> Writes the given int into this buffer at the given
* index. </p>
*
* @param index
* The index at which the int will be written
*
* @param i
* The int value to be written
*
* @return This buffer
*
* @throws IndexOutOfBoundsException
* If <tt>index</tt> is negative
* or not smaller than the buffer's limit
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract IntBuffer put(int index, int i);
// -- Bulk get operations --
/**
* Relative bulk <i>get</i> method.
*
* <p> This method transfers ints from this buffer into the given
* destination array. If there are fewer ints remaining in the
* buffer than are required to satisfy the request, that is, if
* <tt>length</tt>&nbsp;<tt>&gt;</tt>&nbsp;<tt>remaining()</tt>, then no
* ints are transferred and a {@link BufferUnderflowException} is
* thrown.
*
* <p> Otherwise, this method copies <tt>length</tt> ints from this
* buffer into the given array, starting at the current position of this
* buffer and at the given offset in the array. The position of this
* buffer is then incremented by <tt>length</tt>.
*
* <p> In other words, an invocation of this method of the form
* <tt>src.get(dst,&nbsp;off,&nbsp;len)</tt> has exactly the same effect as
* the loop
*
* <pre>{@code
* for (int i = off; i < off + len; i++)
* dst[i] = src.get():
* }</pre>
*
* except that it first checks that there are sufficient ints in
* this buffer and it is potentially much more efficient.
*
* @param dst
* The array into which ints are to be written
*
* @param offset
* The offset within the array of the first int to be
* written; must be non-negative and no larger than
* <tt>dst.length</tt>
*
* @param length
* The maximum number of ints to be written to the given
* array; must be non-negative and no larger than
* <tt>dst.length - offset</tt>
*
* @return This buffer
*
* @throws BufferUnderflowException
* If there are fewer than <tt>length</tt> ints
* remaining in this buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the <tt>offset</tt> and <tt>length</tt>
* parameters do not hold
*/
public IntBuffer get(int[] dst, int offset, int length) {
checkBounds(offset, length, dst.length);
if (length > remaining())
throw new BufferUnderflowException();
int end = offset + length;
for (int i = offset; i < end; i++)
dst[i] = get();
return this;
}
/**
* Relative bulk <i>get</i> method.
*
* <p> This method transfers ints from this buffer into the given
* destination array. An invocation of this method of the form
* <tt>src.get(a)</tt> behaves in exactly the same way as the invocation
*
* <pre>
* src.get(a, 0, a.length) </pre>
*
* @param dst
* The destination array
*
* @return This buffer
*
* @throws BufferUnderflowException
* If there are fewer than <tt>length</tt> ints
* remaining in this buffer
*/
public IntBuffer get(int[] dst) {
return get(dst, 0, dst.length);
}
// -- Bulk put operations --
/**
* Relative bulk <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
*
* <p> This method transfers the ints remaining in the given source
* buffer into this buffer. If there are more ints remaining in the
* source buffer than in this buffer, that is, if
* <tt>src.remaining()</tt>&nbsp;<tt>&gt;</tt>&nbsp;<tt>remaining()</tt>,
* then no ints are transferred and a {@link
* BufferOverflowException} is thrown.
*
* <p> Otherwise, this method copies
* <i>n</i>&nbsp;=&nbsp;<tt>src.remaining()</tt> ints from the given
* buffer into this buffer, starting at each buffer's current position.
* The positions of both buffers are then incremented by <i>n</i>.
*
* <p> In other words, an invocation of this method of the form
* <tt>dst.put(src)</tt> has exactly the same effect as the loop
*
* <pre>
* while (src.hasRemaining())
* dst.put(src.get()); </pre>
*
* except that it first checks that there is sufficient space in this
* buffer and it is potentially much more efficient.
*
* @param src
* The source buffer from which ints are to be read;
* must not be this buffer
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
* for the remaining ints in the source buffer
*
* @throws IllegalArgumentException
* If the source buffer is this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public IntBuffer put(IntBuffer src) {
if (src == this)
throw new IllegalArgumentException();
if (isReadOnly())
throw new ReadOnlyBufferException();
int n = src.remaining();
if (n > remaining())
throw new BufferOverflowException();
for (int i = 0; i < n; i++)
put(src.get());
return this;
}
/**
* Relative bulk <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
*
* <p> This method transfers ints into this buffer from the given
* source array. If there are more ints to be copied from the array
* than remain in this buffer, that is, if
* <tt>length</tt>&nbsp;<tt>&gt;</tt>&nbsp;<tt>remaining()</tt>, then no
* ints are transferred and a {@link BufferOverflowException} is
* thrown.
*
* <p> Otherwise, this method copies <tt>length</tt> ints from the
* given array into this buffer, starting at the given offset in the array
* and at the current position of this buffer. The position of this buffer
* is then incremented by <tt>length</tt>.
*
* <p> In other words, an invocation of this method of the form
* <tt>dst.put(src,&nbsp;off,&nbsp;len)</tt> has exactly the same effect as
* the loop
*
* <pre>{@code
* for (int i = off; i < off + len; i++)
* dst.put(a[i]);
* }</pre>
*
* except that it first checks that there is sufficient space in this
* buffer and it is potentially much more efficient.
*
* @param src
* The array from which ints are to be read
*
* @param offset
* The offset within the array of the first int to be read;
* must be non-negative and no larger than <tt>array.length</tt>
*
* @param length
* The number of ints to be read from the given array;
* must be non-negative and no larger than
* <tt>array.length - offset</tt>
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
*
* @throws IndexOutOfBoundsException
* If the preconditions on the <tt>offset</tt> and <tt>length</tt>
* parameters do not hold
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public IntBuffer put(int[] src, int offset, int length) {
checkBounds(offset, length, src.length);
if (length > remaining())
throw new BufferOverflowException();
int end = offset + length;
for (int i = offset; i < end; i++)
this.put(src[i]);
return this;
}
/**
* Relative bulk <i>put</i> method&nbsp;&nbsp;<i>(optional operation)</i>.
*
* <p> This method transfers the entire content of the given source
* int array into this buffer. An invocation of this method of the
* form <tt>dst.put(a)</tt> behaves in exactly the same way as the
* invocation
*
* <pre>
* dst.put(a, 0, a.length) </pre>
*
* @param src
* The source array
*
* @return This buffer
*
* @throws BufferOverflowException
* If there is insufficient space in this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public final IntBuffer put(int[] src) {
return put(src, 0, src.length);
}
// -- Other stuff --
/**
* Tells whether or not this buffer is backed by an accessible int
* array.
*
* <p> If this method returns <tt>true</tt> then the {@link #array() array}
* and {@link #arrayOffset() arrayOffset} methods may safely be invoked.
* </p>
*
* @return <tt>true</tt> if, and only if, this buffer
* is backed by an array and is not read-only
*/
public final boolean hasArray() {
return (hb != null) && !isReadOnly;
}
/**
* Returns the int array that backs this
* buffer&nbsp;&nbsp;<i>(optional operation)</i>.
*
* <p> Modifications to this buffer's content will cause the returned
* array's content to be modified, and vice versa.
*
* <p> Invoke the {@link #hasArray hasArray} method before invoking this
* method in order to ensure that this buffer has an accessible backing
* array. </p>
*
* @return The array that backs this buffer
*
* @throws ReadOnlyBufferException
* If this buffer is backed by an array but is read-only
*
* @throws UnsupportedOperationException
* If this buffer is not backed by an accessible array
*/
public final int[] array() {
if (hb == null)
throw new UnsupportedOperationException();
if (isReadOnly)
throw new ReadOnlyBufferException();
return hb;
}
/**
* Returns the offset within this buffer's backing array of the first
* element of the buffer&nbsp;&nbsp;<i>(optional operation)</i>.
*
* <p> If this buffer is backed by an array then buffer position <i>p</i>
* corresponds to array index <i>p</i>&nbsp;+&nbsp;<tt>arrayOffset()</tt>.
*
* <p> Invoke the {@link #hasArray hasArray} method before invoking this
* method in order to ensure that this buffer has an accessible backing
* array. </p>
*
* @return The offset within this buffer's array
* of the first element of the buffer
*
* @throws ReadOnlyBufferException
* If this buffer is backed by an array but is read-only
*
* @throws UnsupportedOperationException
* If this buffer is not backed by an accessible array
*/
public final int arrayOffset() {
if (hb == null)
throw new UnsupportedOperationException();
if (isReadOnly)
throw new ReadOnlyBufferException();
return offset;
}
/**
* Compacts this buffer&nbsp;&nbsp;<i>(optional operation)</i>.
*
* <p> The ints between the buffer's current position and its limit,
* if any, are copied to the beginning of the buffer. That is, the
* int at index <i>p</i>&nbsp;=&nbsp;<tt>position()</tt> is copied
* to index zero, the int at index <i>p</i>&nbsp;+&nbsp;1 is copied
* to index one, and so forth until the int at index
* <tt>limit()</tt>&nbsp;-&nbsp;1 is copied to index
* <i>n</i>&nbsp;=&nbsp;<tt>limit()</tt>&nbsp;-&nbsp;<tt>1</tt>&nbsp;-&nbsp;<i>p</i>.
* The buffer's position is then set to <i>n+1</i> and its limit is set to
* its capacity. The mark, if defined, is discarded.
*
* <p> The buffer's position is set to the number of ints copied,
* rather than to zero, so that an invocation of this method can be
* followed immediately by an invocation of another relative <i>put</i>
* method. </p>
*
*
* @return This buffer
*
* @throws ReadOnlyBufferException
* If this buffer is read-only
*/
public abstract IntBuffer compact();
/**
* Tells whether or not this int buffer is direct.
*
* @return <tt>true</tt> if, and only if, this buffer is direct
*/
public abstract boolean isDirect();
/**
* Returns a string summarizing the state of this buffer.
*
* @return A summary string
*/
public String toString() {
StringBuffer sb = new StringBuffer();
sb.append(getClass().getName());
sb.append("[pos=");
sb.append(position());
sb.append(" lim=");
sb.append(limit());
sb.append(" cap=");
sb.append(capacity());
sb.append("]");
return sb.toString();
}
/**
* Returns the current hash code of this buffer.
*
* <p> The hash code of a int buffer depends only upon its remaining
* elements; that is, upon the elements from <tt>position()</tt> up to, and
* including, the element at <tt>limit()</tt>&nbsp;-&nbsp;<tt>1</tt>.
*
* <p> Because buffer hash codes are content-dependent, it is inadvisable
* to use buffers as keys in hash maps or similar data structures unless it
* is known that their contents will not change. </p>
*
* @return The current hash code of this buffer
*/
public int hashCode() {
int h = 1;
int p = position();
for (int i = limit() - 1; i >= p; i--)
h = 31 * h + get(i);
return h;
}
/**
* Tells whether or not this buffer is equal to another object.
*
* <p> Two int buffers are equal if, and only if,
*
* <ol>
*
* <li><p> They have the same element type, </p></li>
*
* <li><p> They have the same number of remaining elements, and
* </p></li>
*
* <li><p> The two sequences of remaining elements, considered
* independently of their starting positions, are pointwise equal.
* </p></li>
*
* </ol>
*
* <p> A int buffer is not equal to any other type of object. </p>
*
* @param ob The object to which this buffer is to be compared
*
* @return <tt>true</tt> if, and only if, this buffer is equal to the
* given object
*/
public boolean equals(Object ob) {
if (this == ob)
return true;
if (!(ob instanceof IntBuffer))
return false;
IntBuffer that = (IntBuffer)ob;
if (this.remaining() != that.remaining())
return false;
int p = this.position();
for (int i = this.limit() - 1, j = that.limit() - 1; i >= p; i--, j--)
if (!equals(this.get(i), that.get(j)))
return false;
return true;
}
private static boolean equals(int x, int y) {
return x == y;
}
/**
* Compares this buffer to another.
*
* <p> Two int buffers are compared by comparing their sequences of
* remaining elements lexicographically, without regard to the starting
* position of each sequence within its corresponding buffer.
* Pairs of {@code int} elements are compared as if by invoking
* {@link Integer#compare(int,int)}.
*
* <p> A int buffer is not comparable to any other type of object.
*
* @return A negative integer, zero, or a positive integer as this buffer
* is less than, equal to, or greater than the given buffer
*/
public int compareTo(IntBuffer that) {
int n = this.position() + Math.min(this.remaining(), that.remaining());
for (int i = this.position(), j = that.position(); i < n; i++, j++) {
int cmp = compare(this.get(i), that.get(j));
if (cmp != 0)
return cmp;
}
return this.remaining() - that.remaining();
}
private static int compare(int x, int y) {
return Integer.compare(x, y);
}
// -- Other char stuff --
// -- Other byte stuff: Access to binary data --
/**
* Retrieves this buffer's byte order.
*
* <p> The byte order of an int buffer created by allocation or by
* wrapping an existing <tt>int</tt> array is the {@link
* ByteOrder#nativeOrder native order} of the underlying
* hardware. The byte order of an int buffer created as a <a
* href="ByteBuffer.html#views">view</a> of a byte buffer is that of the
* byte buffer at the moment that the view is created. </p>
*
* @return This buffer's byte order
*/
public abstract ByteOrder order();
}
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