/* *  gnu/regexp/RETokenOneOf.java *  Copyright (C) 1998-2001 Wes Biggs * *  This library is free software; you can redistribute it and/or modify *  it under the terms of the GNU Lesser General Public License as published *  by the Free Software Foundation; either version 2.1 of the License, or *  (at your option) any later version. * *  This library 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 Lesser General Public License for more details. * *  You should have received a copy of the GNU Lesser General Public License *  along with this program; if not, write to the Free Software *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */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(')');    }}