001/* Pattern.java -- Compiled regular expression ready to be applied. 002 Copyright (C) 2002, 2004, 2005, 2007 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 038package java.util.regex; 039 040import gnu.java.util.regex.RE; 041import gnu.java.util.regex.REException; 042import gnu.java.util.regex.RESyntax; 043 044import java.io.Serializable; 045import java.util.ArrayList; 046 047 048/** 049 * Compiled regular expression ready to be applied. 050 * 051 * @since 1.4 052 */ 053public final class Pattern implements Serializable 054{ 055 private static final long serialVersionUID = 5073258162644648461L; 056 057 public static final int CANON_EQ = 128; 058 public static final int CASE_INSENSITIVE = 2; 059 public static final int COMMENTS = 4; 060 public static final int DOTALL = 32; 061 public static final int MULTILINE = 8; 062 public static final int UNICODE_CASE = 64; 063 public static final int UNIX_LINES = 1; 064 065 private final String regex; 066 private final int flags; 067 068 private final RE re; 069 070 private Pattern (String regex, int flags) 071 throws PatternSyntaxException 072 { 073 this.regex = regex; 074 this.flags = flags; 075 076 RESyntax syntax = RESyntax.RE_SYNTAX_JAVA_1_4; 077 int gnuFlags = 0; 078 gnuFlags |= RE.REG_ICASE_USASCII; 079 if ((flags & CASE_INSENSITIVE) != 0) 080 gnuFlags |= RE.REG_ICASE; 081 if ((flags & MULTILINE) != 0) 082 { 083 gnuFlags |= RE.REG_MULTILINE; 084 syntax = new RESyntax(syntax); 085 syntax.setLineSeparator(null); 086 } 087 if ((flags & DOTALL) != 0) 088 gnuFlags |= RE.REG_DOT_NEWLINE; 089 if ((flags & UNICODE_CASE) != 0) 090 gnuFlags &= ~RE.REG_ICASE_USASCII; 091 // not yet supported: 092 // if ((flags & CANON_EQ) != 0) gnuFlags = 093 094 if ((flags & UNIX_LINES) != 0) 095 { 096 // Use a syntax set with \n for linefeeds? 097 syntax = new RESyntax(syntax); 098 syntax.setLineSeparator("\n"); 099 } 100 101 if ((flags & COMMENTS) != 0) 102 { 103 gnuFlags |= RE.REG_X_COMMENTS; 104 } 105 106 try 107 { 108 this.re = new RE(regex, gnuFlags, syntax); 109 } 110 catch (REException e) 111 { 112 PatternSyntaxException pse; 113 pse = new PatternSyntaxException(e.getMessage(), 114 regex, e.getPosition()); 115 pse.initCause(e); 116 throw pse; 117 } 118 } 119 120 // package private accessor method 121 RE getRE() 122 { 123 return re; 124 } 125 126 /** 127 * @param regex The regular expression 128 * 129 * @exception PatternSyntaxException If the expression's syntax is invalid 130 */ 131 public static Pattern compile (String regex) 132 throws PatternSyntaxException 133 { 134 return compile(regex, 0); 135 } 136 137 /** 138 * @param regex The regular expression 139 * @param flags The match flags, a bit mask 140 * 141 * @exception PatternSyntaxException If the expression's syntax is invalid 142 * @exception IllegalArgumentException If bit values other than those 143 * corresponding to the defined match flags are set in flags 144 */ 145 public static Pattern compile (String regex, int flags) 146 throws PatternSyntaxException 147 { 148 // FIXME: check which flags are really accepted 149 if ((flags & ~0xEF) != 0) 150 throw new IllegalArgumentException (); 151 152 return new Pattern (regex, flags); 153 } 154 155 public int flags () 156 { 157 return this.flags; 158 } 159 160 /** 161 * @param regex The regular expression 162 * @param input The character sequence to be matched 163 * 164 * @exception PatternSyntaxException If the expression's syntax is invalid 165 */ 166 public static boolean matches (String regex, CharSequence input) 167 { 168 return compile(regex).matcher(input).matches(); 169 } 170 171 /** 172 * @param input The character sequence to be matched 173 */ 174 public Matcher matcher (CharSequence input) 175 { 176 return new Matcher(this, input); 177 } 178 179 /** 180 * @param input The character sequence to be matched 181 */ 182 public String[] split (CharSequence input) 183 { 184 return split(input, 0); 185 } 186 187 /** 188 * @param input The character sequence to be matched 189 * @param limit The result threshold 190 */ 191 public String[] split (CharSequence input, int limit) 192 { 193 Matcher matcher = new Matcher(this, input); 194 ArrayList<String> list = new ArrayList<String>(); 195 int empties = 0; 196 int count = 0; 197 int start = 0; 198 int end; 199 boolean matched = matcher.find(); 200 201 while (matched && (limit <= 0 || count < limit - 1)) 202 { 203 ++count; 204 end = matcher.start(); 205 if (start == end) 206 empties++; 207 else 208 { 209 while (empties > 0) 210 { 211 list.add(""); 212 empties--; 213 } 214 215 String text = input.subSequence(start, end).toString(); 216 list.add(text); 217 } 218 start = matcher.end(); 219 matched = matcher.find(); 220 } 221 222 // We matched nothing. 223 if (!matched && count == 0) 224 return new String[] { input.toString() }; 225 226 // Is the last token empty? 227 boolean emptyLast = (start == input.length()); 228 229 // Can/Must we add empties or an extra last token at the end? 230 if (list.size() < limit || limit < 0 || (limit == 0 && !emptyLast)) 231 { 232 if (limit > list.size()) 233 { 234 int max = limit - list.size(); 235 empties = (empties > max) ? max : empties; 236 } 237 while (empties > 0) 238 { 239 list.add(""); 240 empties--; 241 } 242 } 243 244 // last token at end 245 if (limit != 0 || (limit == 0 && !emptyLast)) 246 { 247 String t = input.subSequence(start, input.length()).toString(); 248 if ("".equals(t) && limit == 0) 249 { /* Don't add. */ } 250 else 251 list.add(t); 252 } 253 254 return list.toArray(new String[list.size()]); 255 } 256 257 public String pattern () 258 { 259 return regex; 260 } 261 262 /** 263 * Return the regular expression used to construct this object. 264 * @specnote Prior to JDK 1.5 this method had a different behavior 265 * @since 1.5 266 */ 267 public String toString() 268 { 269 return regex; 270 } 271}