X-Git-Url: https://git.mdrn.pl/pylucene.git/blobdiff_plain/a2e61f0c04805cfcb8706176758d1283c7e3a55c..aaeed5504b982cf3545252ab528713250aa33eed:/lucene-java-3.5.0/lucene/contrib/analyzers/common/src/java/org/apache/lucene/analysis/id/IndonesianAnalyzer.java?ds=sidebyside diff --git a/lucene-java-3.5.0/lucene/contrib/analyzers/common/src/java/org/apache/lucene/analysis/id/IndonesianAnalyzer.java b/lucene-java-3.5.0/lucene/contrib/analyzers/common/src/java/org/apache/lucene/analysis/id/IndonesianAnalyzer.java new file mode 100644 index 0000000..1e1879d --- /dev/null +++ b/lucene-java-3.5.0/lucene/contrib/analyzers/common/src/java/org/apache/lucene/analysis/id/IndonesianAnalyzer.java @@ -0,0 +1,130 @@ +package org.apache.lucene.analysis.id; + +/** + * 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 java.io.Reader; +import java.util.Set; + +import org.apache.lucene.analysis.CharArraySet; +import org.apache.lucene.analysis.KeywordMarkerFilter; +import org.apache.lucene.analysis.LowerCaseFilter; +import org.apache.lucene.analysis.StopFilter; +import org.apache.lucene.analysis.StopwordAnalyzerBase; +import org.apache.lucene.analysis.TokenStream; +import org.apache.lucene.analysis.Tokenizer; +import org.apache.lucene.analysis.standard.StandardFilter; +import org.apache.lucene.analysis.standard.StandardTokenizer; +import org.apache.lucene.util.Version; + +/** + * Analyzer for Indonesian (Bahasa) + */ +public final class IndonesianAnalyzer extends StopwordAnalyzerBase { + /** File containing default Indonesian stopwords. */ + public final static String DEFAULT_STOPWORD_FILE = "stopwords.txt"; + + /** + * Returns an unmodifiable instance of the default stop-words set. + * @return an unmodifiable instance of the default stop-words set. + */ + public static Set getDefaultStopSet(){ + return DefaultSetHolder.DEFAULT_STOP_SET; + } + + /** + * Atomically loads the DEFAULT_STOP_SET in a lazy fashion once the outer class + * accesses the static final set the first time.; + */ + private static class DefaultSetHolder { + static final Set DEFAULT_STOP_SET; + + static { + try { + DEFAULT_STOP_SET = loadStopwordSet(false, IndonesianAnalyzer.class, DEFAULT_STOPWORD_FILE, "#"); + } catch (IOException ex) { + // default set should always be present as it is part of the + // distribution (JAR) + throw new RuntimeException("Unable to load default stopword set"); + } + } + } + + private final Set stemExclusionSet; + + /** + * Builds an analyzer with the default stop words: {@link #DEFAULT_STOPWORD_FILE}. + */ + public IndonesianAnalyzer(Version matchVersion) { + this(matchVersion, DefaultSetHolder.DEFAULT_STOP_SET); + } + + /** + * Builds an analyzer with the given stop words + * + * @param matchVersion + * lucene compatibility version + * @param stopwords + * a stopword set + */ + public IndonesianAnalyzer(Version matchVersion, Set stopwords){ + this(matchVersion, stopwords, CharArraySet.EMPTY_SET); + } + + /** + * Builds an analyzer with the given stop word. If a none-empty stem exclusion set is + * provided this analyzer will add a {@link KeywordMarkerFilter} before + * {@link IndonesianStemFilter}. + * + * @param matchVersion + * lucene compatibility version + * @param stopwords + * a stopword set + * @param stemExclusionSet + * a set of terms not to be stemmed + */ + public IndonesianAnalyzer(Version matchVersion, Set stopwords, Set stemExclusionSet){ + super(matchVersion, stopwords); + this.stemExclusionSet = CharArraySet.unmodifiableSet(CharArraySet.copy( + matchVersion, stemExclusionSet)); + } + + /** + * Creates + * {@link org.apache.lucene.analysis.ReusableAnalyzerBase.TokenStreamComponents} + * used to tokenize all the text in the provided {@link Reader}. + * + * @return {@link org.apache.lucene.analysis.ReusableAnalyzerBase.TokenStreamComponents} + * built from an {@link StandardTokenizer} filtered with + * {@link StandardFilter}, {@link LowerCaseFilter}, + * {@link StopFilter}, {@link KeywordMarkerFilter} + * if a stem exclusion set is provided and {@link IndonesianStemFilter}. + */ + @Override + protected TokenStreamComponents createComponents(String fieldName, + Reader reader) { + final Tokenizer source = new StandardTokenizer(matchVersion, reader); + TokenStream result = new StandardFilter(matchVersion, source); + result = new LowerCaseFilter(matchVersion, result); + result = new StopFilter(matchVersion, result, stopwords); + if (!stemExclusionSet.isEmpty()) { + result = new KeywordMarkerFilter(result, stemExclusionSet); + } + return new TokenStreamComponents(source, new IndonesianStemFilter(result)); + } +}