org.apache.lucene.analysis.standard.UAX29URLEmailAnalyzer Maven / Gradle / Ivy
package org.apache.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 org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.core.LowerCaseFilter;
import org.apache.lucene.analysis.core.StopAnalyzer;
import org.apache.lucene.analysis.core.StopFilter;
import org.apache.lucene.analysis.util.CharArraySet;
import org.apache.lucene.analysis.util.StopwordAnalyzerBase;
import org.apache.lucene.util.Version;
import java.io.IOException;
import java.io.Reader;
/**
* Filters {@link org.apache.lucene.analysis.standard.UAX29URLEmailTokenizer}
* with {@link org.apache.lucene.analysis.standard.StandardFilter},
* {@link org.apache.lucene.analysis.core.LowerCaseFilter} and
* {@link org.apache.lucene.analysis.core.StopFilter}, using a list of
* English stop words.
*
*
*
* You must specify the required {@link org.apache.lucene.util.Version}
* compatibility when creating UAX29URLEmailAnalyzer
*
*/
public final class UAX29URLEmailAnalyzer extends StopwordAnalyzerBase {
/** Default maximum allowed token length */
public static final int DEFAULT_MAX_TOKEN_LENGTH = StandardAnalyzer.DEFAULT_MAX_TOKEN_LENGTH;
private int maxTokenLength = DEFAULT_MAX_TOKEN_LENGTH;
/** An unmodifiable set containing some common English words that are usually not
useful for searching. */
public static final CharArraySet STOP_WORDS_SET = StopAnalyzer.ENGLISH_STOP_WORDS_SET;
/** Builds an analyzer with the given stop words.
* @param matchVersion Lucene version to match See {@link
* above}
* @param stopWords stop words */
public UAX29URLEmailAnalyzer(Version matchVersion, CharArraySet stopWords) {
super(matchVersion, stopWords);
}
/** Builds an analyzer with the default stop words ({@link
* #STOP_WORDS_SET}).
* @param matchVersion Lucene version to match See {@link
* above}
*/
public UAX29URLEmailAnalyzer(Version matchVersion) {
this(matchVersion, STOP_WORDS_SET);
}
/** Builds an analyzer with the stop words from the given reader.
* @see org.apache.lucene.analysis.util.WordlistLoader#getWordSet(java.io.Reader, org.apache.lucene.util.Version)
* @param matchVersion Lucene version to match See {@link
* above}
* @param stopwords Reader to read stop words from */
public UAX29URLEmailAnalyzer(Version matchVersion, Reader stopwords) throws IOException {
this(matchVersion, loadStopwordSet(stopwords, matchVersion));
}
/**
* Set maximum allowed token length. If a token is seen
* that exceeds this length then it is discarded. This
* setting only takes effect the next time tokenStream or
* tokenStream is called.
*/
public void setMaxTokenLength(int length) {
maxTokenLength = length;
}
/**
* @see #setMaxTokenLength
*/
public int getMaxTokenLength() {
return maxTokenLength;
}
@Override
protected TokenStreamComponents createComponents(final String fieldName, final Reader reader) {
final UAX29URLEmailTokenizer src = new UAX29URLEmailTokenizer(matchVersion, reader);
src.setMaxTokenLength(maxTokenLength);
TokenStream tok = new StandardFilter(matchVersion, src);
tok = new LowerCaseFilter(matchVersion, tok);
tok = new StopFilter(matchVersion, tok, stopwords);
return new TokenStreamComponents(src, tok) {
@Override
protected void setReader(final Reader reader) throws IOException {
src.setMaxTokenLength(UAX29URLEmailAnalyzer.this.maxTokenLength);
super.setReader(reader);
}
};
}
}