| /* gnu/regexp/RETokenLookAhead.java |
| Copyright (C) 1998-2001, 2004 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., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 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 |
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| exception statement from your version. */ |
| |
| package gnu.regexp; |
| |
| /** |
| * @since gnu.regexp 1.1.3 |
| * @author Shashank Bapat |
| */ |
| final class RETokenLookAhead extends REToken |
| { |
| REToken re; |
| boolean negative; |
| |
| RETokenLookAhead(REToken re, boolean negative) throws REException { |
| super(0); |
| this.re = re; |
| this.negative = negative; |
| } |
| |
| boolean match(CharIndexed input, REMatch mymatch) |
| { |
| REMatch trymatch = (REMatch)mymatch.clone(); |
| REMatch trymatch1 = (REMatch)mymatch.clone(); |
| REMatch newMatch = null; |
| if (re.match(input, trymatch)) { |
| if (negative) return false; |
| if (next(input, trymatch1)) |
| newMatch = trymatch1; |
| } |
| |
| if (newMatch != null) { |
| if (negative) return false; |
| //else |
| mymatch.assignFrom(newMatch); |
| return true; |
| } |
| else { // no match |
| if (negative) |
| return next(input, mymatch); |
| //else |
| return false; |
| } |
| } |
| |
| void dump(StringBuffer os) { |
| os.append("(?"); |
| os.append(negative ? '!' : '='); |
| re.dumpAll(os); |
| os.append(')'); |
| } |
| } |
| |