/**
* License Agreement for OpenSearchServer
*
* Copyright (C) 2012-2013 Emmanuel Keller / Jaeksoft
*
* http://www.open-search-server.com
*
* This file is part of OpenSearchServer.
*
* OpenSearchServer 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 3 of the License, or
* (at your option) any later version.
*
* OpenSearchServer 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 OpenSearchServer.
* If not, see <http://www.gnu.org/licenses/>.
**/
package com.jaeksoft.searchlib.analysis.filter.stop;
import java.io.IOException;
import org.apache.lucene.analysis.TokenStream;
import com.jaeksoft.searchlib.analysis.filter.AbstractTermFilter;
public class StopWordFilter extends AbstractTermFilter {
private final WordArray wordArray;
private final boolean ignoreCase;
public StopWordFilter(TokenStream input, WordArray wordArray,
boolean ignoreCase) {
super(input);
this.wordArray = wordArray;
this.ignoreCase = ignoreCase;
}
private final boolean keepTerm(String term) {
if (wordArray == null)
return true;
if (ignoreCase)
term = term.toLowerCase();
return !wordArray.match(term);
}
@Override
public final boolean incrementToken() throws IOException {
int skippedPositions = 0;
for (;;) {
if (!input.incrementToken())
return false;
if (keepTerm(termAtt.toString())) {
posIncrAtt.setPositionIncrement(posIncrAtt
.getPositionIncrement() + skippedPositions);
return true;
}
skippedPositions += posIncrAtt.getPositionIncrement();
}
}
}