| /* gnu/regexp/RETokenLookBehind.java |
| Copyright (C) 2006 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 |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| 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 |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package gnu.java.util.regex; |
| |
| import gnu.java.lang.CPStringBuilder; |
| |
| /** |
| * @author Ito Kazumitsu |
| */ |
| final class RETokenLookBehind extends REToken |
| { |
| REToken re; |
| boolean negative; |
| |
| RETokenLookBehind (REToken re, boolean negative) throws REException |
| { |
| super (0); |
| this.re = re; |
| this.negative = negative; |
| } |
| |
| int getMaximumLength () |
| { |
| return 0; |
| } |
| |
| REMatch matchThis (CharIndexed input, REMatch mymatch) |
| { |
| int max = re.getMaximumLength (); |
| CharIndexed behind = input.lookBehind (mymatch.index, max); |
| REMatch trymatch = (REMatch) mymatch.clone (); |
| int diff = behind.length () - input.length (); |
| int curIndex = trymatch.index + diff; |
| trymatch.index = 0; |
| trymatch.offset = 0; |
| RETokenMatchHereOnly stopper = new RETokenMatchHereOnly (curIndex); |
| REToken re1 = (REToken) re.clone (); |
| re1.chain (stopper); |
| if (re1.match (behind, trymatch)) |
| { |
| if (negative) |
| return null; |
| for (int i = 0; i < trymatch.start.length; i++) |
| { |
| if (trymatch.start[i] != -1 && trymatch.end[i] != -1) |
| { |
| trymatch.start[i] -= diff; |
| if (trymatch.start[i] < 0) |
| trymatch.start[i] -= 1; |
| trymatch.end[i] -= diff; |
| if (trymatch.end[i] < 0) |
| trymatch.end[i] -= 1; |
| } |
| } |
| trymatch.index = mymatch.index; |
| trymatch.offset = mymatch.offset; |
| return trymatch; |
| } |
| else |
| { |
| if (negative) |
| return mymatch; |
| return null; |
| } |
| } |
| |
| void dump (CPStringBuilder os) |
| { |
| os.append ("(?<"); |
| os.append (negative ? '!' : '='); |
| re.dumpAll (os); |
| os.append (')'); |
| } |
| |
| private static class RETokenMatchHereOnly extends REToken |
| { |
| |
| int getMaximumLength () |
| { |
| return 0; |
| } |
| |
| private int index; |
| |
| RETokenMatchHereOnly (int index) |
| { |
| super (0); |
| this.index = index; |
| } |
| |
| REMatch matchThis (CharIndexed input, REMatch mymatch) |
| { |
| return (index == mymatch.index ? mymatch : null); |
| } |
| |
| void dump (CPStringBuilder os) |
| { |
| } |
| |
| } |
| } |