/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.lucene.analysis.tr;
import org.apache.lucene.analysis.TokenFilter;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
import java.io.IOException;
/**
* Strips all characters after an apostrophe (including the apostrophe itself).
* <p>
* In Turkish, apostrophe is used to separate suffixes from proper names
* (continent, sea, river, lake, mountain, upland, proper names related to
* religion and mythology). This filter intended to be used before stem filters.
* For more information, see <a href="http://www.ipcsit.com/vol57/015-ICNI2012-M021.pdf">
* Role of Apostrophes in Turkish Information Retrieval</a>
* </p>
*/
public final class ApostropheFilter extends TokenFilter {
private final CharTermAttribute termAtt = addAttribute(CharTermAttribute.class);
public ApostropheFilter(TokenStream in) {
super(in);
}
@Override
public final boolean incrementToken() throws IOException {
if (!input.incrementToken())
return false;
final char[] buffer = termAtt.buffer();
final int length = termAtt.length();
for (int i = 0; i < length; i++)
if (buffer[i] == '\'' || buffer[i] == '\u2019') {
termAtt.setLength(i);
return true;
}
return true;
}
}