Source for java.lang.Number

   1: /* Number.java =- abstract superclass of numeric objects
   2:    Copyright (C) 1998, 2001, 2002, 2005  Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: 
  39: package java.lang;
  40: 
  41: import java.io.Serializable;
  42: 
  43: /**
  44:  * Number is a generic superclass of all the numeric classes, including
  45:  * the wrapper classes {@link Byte}, {@link Short}, {@link Integer},
  46:  * {@link Long}, {@link Float}, and {@link Double}.  Also worth mentioning
  47:  * are the classes in {@link java.math}.
  48:  *
  49:  * It provides ways to convert numeric objects to any primitive.
  50:  *
  51:  * @author Paul Fisher
  52:  * @author John Keiser
  53:  * @author Warren Levy
  54:  * @author Eric Blake (ebb9@email.byu.edu)
  55:  * @since 1.0
  56:  * @status updated to 1.4
  57:  */
  58: public abstract class Number implements Serializable
  59: {
  60:   /**
  61:    * Compatible with JDK 1.1+.
  62:    */
  63:   private static final long serialVersionUID = -8742448824652078965L;
  64: 
  65:   /**
  66:    * Table for calculating digits, used in Character, Long, and Integer.
  67:    */
  68:   static final char[] digits = {
  69:     '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
  70:     'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
  71:     'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't',
  72:     'u', 'v', 'w', 'x', 'y', 'z',
  73:   };
  74: 
  75:   /**
  76:    * The basic constructor (often called implicitly).
  77:    */
  78:   public Number()
  79:   {
  80:   }
  81: 
  82:   /**
  83:    * Return the value of this <code>Number</code> as an <code>int</code>.
  84:    *
  85:    * @return the int value
  86:    */
  87:   public abstract int intValue();
  88: 
  89:   /**
  90:    * Return the value of this <code>Number</code> as a <code>long</code>.
  91:    *
  92:    * @return the long value
  93:    */
  94:   public abstract long longValue();
  95: 
  96:   /**
  97:    * Return the value of this <code>Number</code> as a <code>float</code>.
  98:    *
  99:    * @return the float value
 100:    */
 101:   public abstract float floatValue();
 102: 
 103:   /**
 104:    * Return the value of this <code>Number</code> as a <code>float</code>.
 105:    *
 106:    * @return the double value
 107:    */
 108:   public abstract double doubleValue();
 109: 
 110:   /**
 111:    * Return the value of this <code>Number</code> as a <code>byte</code>.
 112:    *
 113:    * @return the byte value
 114:    * @since 1.1
 115:    */
 116:   public byte byteValue()
 117:   {
 118:     return (byte) intValue();
 119:   }
 120: 
 121:   /**
 122:    * Return the value of this <code>Number</code> as a <code>short</code>.
 123:    *
 124:    * @return the short value
 125:    * @since 1.1
 126:    */
 127:   public short shortValue()
 128:   {
 129:     return (short) intValue();
 130:   }
 131: }