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/*
* Copyright (c) 1994, 2011, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package java.lang;
/**
* The abstract class {@code Number} is the superclass of platform
* classes representing numeric values that are convertible to the
* primitive types {@code byte}, {@code double}, {@code float}, {@code
* int}, {@code long}, and {@code short}.
*
* The specific semantics of the conversion from the numeric value of
* a particular {@code Number} implementation to a given primitive
* type is defined by the {@code Number} implementation in question.
*
* For platform classes, the conversion is often analogous to a
* narrowing primitive conversion or a widening primitive conversion
* as defining in <cite>The Java&trade; Language Specification</cite>
* for converting between primitive types. Therefore, conversions may
* lose information about the overall magnitude of a numeric value, may
* lose precision, and may even return a result of a different sign
* than the input.
*
* See the documentation of a given {@code Number} implementation for
* conversion details.
*
* @author Lee Boynton
* @author Arthur van Hoff
* @jls 5.1.2 Widening Primitive Conversions
* @jls 5.1.3 Narrowing Primitive Conversions
* @since JDK1.0
*/
public abstract class Number implements java.io.Serializable {
/**
* Returns the value of the specified number as an {@code int},
* which may involve rounding or truncation.
*
* @return the numeric value represented by this object after conversion
* to type {@code int}.
*/
public abstract int intValue();
/**
* Returns the value of the specified number as a {@code long},
* which may involve rounding or truncation.
*
* @return the numeric value represented by this object after conversion
* to type {@code long}.
*/
public abstract long longValue();
/**
* Returns the value of the specified number as a {@code float},
* which may involve rounding.
*
* @return the numeric value represented by this object after conversion
* to type {@code float}.
*/
public abstract float floatValue();
/**
* Returns the value of the specified number as a {@code double},
* which may involve rounding.
*
* @return the numeric value represented by this object after conversion
* to type {@code double}.
*/
public abstract double doubleValue();
/**
* Returns the value of the specified number as a {@code byte},
* which may involve rounding or truncation.
*
* <p>This implementation returns the result of {@link #intValue} cast
* to a {@code byte}.
*
* @return the numeric value represented by this object after conversion
* to type {@code byte}.
* @since JDK1.1
*/
public byte byteValue() {
return (byte)intValue();
}
/**
* Returns the value of the specified number as a {@code short},
* which may involve rounding or truncation.
*
* <p>This implementation returns the result of {@link #intValue} cast
* to a {@code short}.
*
* @return the numeric value represented by this object after conversion
* to type {@code short}.
* @since JDK1.1
*/
public short shortValue() {
return (short)intValue();
}
/** use serialVersionUID from JDK 1.0.2 for interoperability */
private static final long serialVersionUID = -8742448824652078965L;
}