001/* Number.java =- abstract superclass of numeric objects 002 Copyright (C) 1998, 2001, 2002, 2005 Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038 039package java.lang; 040 041import java.io.Serializable; 042 043/** 044 * Number is a generic superclass of all the numeric classes, including 045 * the wrapper classes {@link Byte}, {@link Short}, {@link Integer}, 046 * {@link Long}, {@link Float}, and {@link Double}. Also worth mentioning 047 * are the classes in {@link java.math}. 048 * 049 * It provides ways to convert numeric objects to any primitive. 050 * 051 * @author Paul Fisher 052 * @author John Keiser 053 * @author Warren Levy 054 * @author Eric Blake (ebb9@email.byu.edu) 055 * @since 1.0 056 * @status updated to 1.4 057 */ 058public abstract class Number implements Serializable 059{ 060 /** 061 * Compatible with JDK 1.1+. 062 */ 063 private static final long serialVersionUID = -8742448824652078965L; 064 065 /** 066 * Table for calculating digits, used in Character, Long, and Integer. 067 */ 068 static final char[] digits = { 069 '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 070 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 071 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 072 'u', 'v', 'w', 'x', 'y', 'z', 073 }; 074 075 /** 076 * The basic constructor (often called implicitly). 077 */ 078 public Number() 079 { 080 } 081 082 /** 083 * Return the value of this <code>Number</code> as an <code>int</code>. 084 * 085 * @return the int value 086 */ 087 public abstract int intValue(); 088 089 /** 090 * Return the value of this <code>Number</code> as a <code>long</code>. 091 * 092 * @return the long value 093 */ 094 public abstract long longValue(); 095 096 /** 097 * Return the value of this <code>Number</code> as a <code>float</code>. 098 * 099 * @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}