gcc/libjava/java/lang/Number.java

/* Number.java =- abstract superclass of numeric objects
   Copyright (C) 1998, 2001, 2002 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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GNU Classpath is distributed in the hope that it will be useful, but
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.

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Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

Linking this library statically or dynamically with other modules is
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
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this exception to your version of the library, but you are not
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package java.lang;

import java.io.Serializable;

/**
 * Number is a generic superclass of all the numeric classes, including
 * the wrapper classes {@link Byte}, {@link Short}, {@link Integer},
 * {@link Long}, {@link Float}, and {@link Double}.  Also worth mentioning
 * are the classes in {@link java.math}.
 *
 * It provides ways to convert numeric objects to any primitive.
 *
 * @author Paul Fisher
 * @author John Keiser
 * @author Warren Levy
 * @author Eric Blake <ebb9@email.byu.edu>
 * @since 1.0
 * @status updated to 1.4
 */
public abstract class Number implements Serializable
{
  /**
   * Compatible with JDK 1.1+.
   */
  private static final long serialVersionUID = -8742448824652078965L;

  /**
   * Table for calculating digits, used in Character, Long, and Integer.
   */
  static final char[] digits = {
    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
    'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
    'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't',
    'u', 'v', 'w', 'x', 'y', 'z',
  };

  /**
   * The basic constructor (often called implicitly).
   */
  public Number()
  {
  }

  /**
   * Return the value of this <code>Number</code> as an <code>int</code>.
   *
   * @return the int value
   */
  public abstract int intValue();

  /**
   * Return the value of this <code>Number</code> as a <code>long</code>.
   *
   * @return the long value
   */
  public abstract long longValue();

  /**
   * Return the value of this <code>Number</code> as a <code>float</code>.
   *
   * @return the float value
   */
  public abstract float floatValue();

  /**
   * Return the value of this <code>Number</code> as a <code>float</code>.
   *
   * @return the double value
   */
  public abstract double doubleValue();

  /**
   * Return the value of this <code>Number</code> as a <code>byte</code>.
   *
   * @return the byte value
   * @since 1.1
   */
  public byte byteValue()
  {
    return (byte) intValue();
  }

  /**
   * Return the value of this <code>Number</code> as a <code>short</code>.
   *
   * @return the short value
   * @since 1.1
   */
  public short shortValue()
  {
    return (short) intValue();
  }
}