001/* Format.java -- Abstract superclass for formatting/parsing strings. 002 Copyright (C) 1998, 1999, 2000, 2001, 2003, 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.text; 040 041import gnu.java.text.FormatCharacterIterator; 042 043import java.io.Serializable; 044 045/** 046 * This class is the abstract superclass of classes that format and parse 047 * data to/from <code>Strings</code>. It is guaranteed that any 048 * <code>String</code> produced by a concrete subclass of <code>Format</code> 049 * will be parseable by that same subclass. 050 * <p> 051 * In addition to implementing the abstract methods in this class, subclasses 052 * should provide static factory methods of the form 053 * <code>getInstance()</code> and <code>getInstance(Locale)</code> if the 054 * subclass loads different formatting/parsing schemes based on locale. 055 * These subclasses should also implement a static method called 056 * <code>getAvailableLocales()</code> which returns an array of 057 * available locales in the current runtime environment. 058 * 059 * @author Aaron M. Renn (arenn@urbanophile.com) 060 * @author Per Bothner (bothner@cygnus.com) 061 */ 062public abstract class Format implements Serializable, Cloneable 063{ 064 /** 065 * For compatability with Sun's JDK 1.4.2 rev. 5 066 */ 067 static final long serialVersionUID = -299282585814624189L; 068 069 public static class Field extends AttributedCharacterIterator.Attribute 070 { 071 static final long serialVersionUID = 276966692217360283L; 072 073 protected Field(String name) 074 { 075 super(name); 076 } 077 } 078 079 /** 080 * This method initializes a new instance of <code>Format</code>. 081 * It performs no actions, but acts as a default constructor for 082 * subclasses. 083 */ 084 protected Format () 085 { 086 } 087 088 /** 089 * This method formats an <code>Object</code> into a <code>String</code>. 090 * 091 * @param obj The <code>Object</code> to format. 092 * 093 * @return The formatted <code>String</code>. 094 * 095 * @exception IllegalArgumentException If the <code>Object</code> 096 * cannot be formatted. 097 */ 098 public final String format(Object obj) throws IllegalArgumentException 099 { 100 StringBuffer sb = new StringBuffer (); 101 format (obj, sb, new FieldPosition (0)); 102 return sb.toString (); 103 } 104 105 /** 106 * This method formats an <code>Object</code> into a <code>String</code> and 107 * appends the <code>String</code> to a <code>StringBuffer</code>. 108 * 109 * @param obj The <code>Object</code> to format. 110 * @param sb The <code>StringBuffer</code> to append to. 111 * @param pos The desired <code>FieldPosition</code>, which is also 112 * updated by this call. 113 * 114 * @return The updated <code>StringBuffer</code>. 115 * 116 * @exception IllegalArgumentException If the <code>Object</code> 117 * cannot be formatted. 118 */ 119 public abstract StringBuffer format (Object obj, StringBuffer sb, 120 FieldPosition pos) 121 throws IllegalArgumentException; 122 123 /** 124 * This method parses a <code>String</code> and converts the parsed 125 * contents into an <code>Object</code>. 126 * 127 * @param str The <code>String</code> to parse. 128 * 129 * @return The resulting <code>Object</code>. 130 * 131 * @exception ParseException If the <code>String</code> cannot be parsed. 132 */ 133 public Object parseObject (String str) throws ParseException 134 { 135 ParsePosition pos = new ParsePosition(0); 136 Object result = parseObject (str, pos); 137 if (result == null) 138 { 139 int index = pos.getErrorIndex(); 140 if (index < 0) 141 index = pos.getIndex(); 142 throw new ParseException("parseObject failed", index); 143 } 144 return result; 145 } 146 147 /** 148 * This method parses a <code>String</code> and converts the parsed 149 * contents into an <code>Object</code>. 150 * 151 * @param str The <code>String</code> to parse. 152 * @param pos The starting parse index on input, the ending parse 153 * index on output. 154 * 155 * @return The parsed <code>Object</code>, or <code>null</code> in 156 * case of error. 157 */ 158 public abstract Object parseObject (String str, ParsePosition pos); 159 160 public AttributedCharacterIterator formatToCharacterIterator(Object obj) 161 { 162 return new FormatCharacterIterator(format(obj), null, null); 163 } 164 165 /** 166 * Creates a copy of this object. 167 * 168 * @return The copied <code>Object</code>. 169 */ 170 public Object clone () 171 { 172 try 173 { 174 return super.clone (); 175 } 176 catch (CloneNotSupportedException e) 177 { 178 return null; 179 } 180 } 181}