org.trypticon.luceneupgrader.lucene3.internal.lucene.analysis.standard.StandardFilter Maven / Gradle / Ivy
package org.trypticon.luceneupgrader.lucene3.internal.lucene.analysis.standard;
/**
* 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.
*/
import java.io.IOException;
import org.trypticon.luceneupgrader.lucene3.internal.lucene.analysis.TokenFilter;
import org.trypticon.luceneupgrader.lucene3.internal.lucene.analysis.TokenStream;
import org.trypticon.luceneupgrader.lucene3.internal.lucene.analysis.tokenattributes.CharTermAttribute;
import org.trypticon.luceneupgrader.lucene3.internal.lucene.analysis.tokenattributes.TypeAttribute;
import org.trypticon.luceneupgrader.lucene3.internal.lucene.util.Version;
/**
* Normalizes tokens extracted with {@link StandardTokenizer}.
*/
public class StandardFilter extends TokenFilter {
private final Version matchVersion;
/** @deprecated Use {@link #StandardFilter(Version, TokenStream)} instead. */
@Deprecated
public StandardFilter(TokenStream in) {
this(Version.LUCENE_30, in);
}
public StandardFilter(Version matchVersion, TokenStream in) {
super(in);
this.matchVersion = matchVersion;
}
private static final String APOSTROPHE_TYPE = ClassicTokenizer.TOKEN_TYPES[ClassicTokenizer.APOSTROPHE];
private static final String ACRONYM_TYPE = ClassicTokenizer.TOKEN_TYPES[ClassicTokenizer.ACRONYM];
// this filters uses attribute type
private final TypeAttribute typeAtt = addAttribute(TypeAttribute.class);
private final CharTermAttribute termAtt = addAttribute(CharTermAttribute.class);
@Override
public final boolean incrementToken() throws IOException {
if (matchVersion.onOrAfter(Version.LUCENE_31))
return input.incrementToken(); // TODO: add some niceties for the new grammar
else
return incrementTokenClassic();
}
public final boolean incrementTokenClassic() throws IOException {
if (!input.incrementToken()) {
return false;
}
final char[] buffer = termAtt.buffer();
final int bufferLength = termAtt.length();
final String type = typeAtt.type();
if (type == APOSTROPHE_TYPE && // remove 's
bufferLength >= 2 &&
buffer[bufferLength-2] == '\'' &&
(buffer[bufferLength-1] == 's' || buffer[bufferLength-1] == 'S')) {
// Strip last 2 characters off
termAtt.setLength(bufferLength - 2);
} else if (type == ACRONYM_TYPE) { // remove dots
int upto = 0;
for(int i=0;i