+++ /dev/null
-package org.apache.lucene.analysis.fa;
-
-/**
- * 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.File;
-import java.io.IOException;
-import java.io.Reader;
-import java.util.Hashtable;
-import java.util.Set;
-
-import org.apache.lucene.analysis.Analyzer;
-import org.apache.lucene.analysis.LowerCaseFilter;
-import org.apache.lucene.analysis.StopFilter;
-import org.apache.lucene.analysis.StopwordAnalyzerBase;
-import org.apache.lucene.analysis.CharReader;
-import org.apache.lucene.analysis.TokenStream;
-import org.apache.lucene.analysis.Tokenizer;
-import org.apache.lucene.analysis.WordlistLoader;
-import org.apache.lucene.analysis.ar.ArabicLetterTokenizer;
-import org.apache.lucene.analysis.ar.ArabicNormalizationFilter;
-import org.apache.lucene.analysis.standard.StandardTokenizer;
-
-import org.apache.lucene.util.Version;
-
-/**
- * {@link Analyzer} for Persian.
- * <p>
- * This Analyzer uses {@link ArabicLetterTokenizer} which implies tokenizing around
- * zero-width non-joiner in addition to whitespace. Some persian-specific variant forms (such as farsi
- * yeh and keheh) are standardized. "Stemming" is accomplished via stopwords.
- * </p>
- */
-public final class PersianAnalyzer extends StopwordAnalyzerBase {
-
- /**
- * File containing default Persian stopwords.
- *
- * Default stopword list is from
- * http://members.unine.ch/jacques.savoy/clef/index.html The stopword list is
- * BSD-Licensed.
- *
- */
- public final static String DEFAULT_STOPWORD_FILE = "stopwords.txt";
-
- /**
- * The comment character in the stopwords file. All lines prefixed with this
- * will be ignored
- */
- public static final String STOPWORDS_COMMENT = "#";
-
- /**
- * 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, PersianAnalyzer.class, DEFAULT_STOPWORD_FILE, STOPWORDS_COMMENT);
- } 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");
- }
- }
- }
-
- /**
- * Builds an analyzer with the default stop words:
- * {@link #DEFAULT_STOPWORD_FILE}.
- */
- public PersianAnalyzer(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 PersianAnalyzer(Version matchVersion, Set<?> stopwords){
- super(matchVersion, stopwords);
- }
-
- /**
- * Builds an analyzer with the given stop words.
- * @deprecated use {@link #PersianAnalyzer(Version, Set)} instead
- */
- @Deprecated
- public PersianAnalyzer(Version matchVersion, String... stopwords) {
- this(matchVersion, StopFilter.makeStopSet(matchVersion, stopwords));
- }
-
- /**
- * Builds an analyzer with the given stop words.
- * @deprecated use {@link #PersianAnalyzer(Version, Set)} instead
- */
- @Deprecated
- public PersianAnalyzer(Version matchVersion, Hashtable<?, ?> stopwords) {
- this(matchVersion, stopwords.keySet());
- }
-
- /**
- * Builds an analyzer with the given stop words. Lines can be commented out
- * using {@link #STOPWORDS_COMMENT}
- * @deprecated use {@link #PersianAnalyzer(Version, Set)} instead
- */
- @Deprecated
- public PersianAnalyzer(Version matchVersion, File stopwords) throws IOException {
- this(matchVersion, WordlistLoader.getWordSet(stopwords, STOPWORDS_COMMENT));
- }
-
- /**
- * 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 a {@link StandardTokenizer} filtered with
- * {@link LowerCaseFilter}, {@link ArabicNormalizationFilter},
- * {@link PersianNormalizationFilter} and Persian Stop words
- */
- @Override
- protected TokenStreamComponents createComponents(String fieldName,
- Reader reader) {
- final Tokenizer source;
- if (matchVersion.onOrAfter(Version.LUCENE_31)) {
- source = new StandardTokenizer(matchVersion, reader);
- } else {
- source = new ArabicLetterTokenizer(matchVersion, reader);
- }
- TokenStream result = new LowerCaseFilter(matchVersion, source);
- result = new ArabicNormalizationFilter(result);
- /* additional persian-specific normalization */
- result = new PersianNormalizationFilter(result);
- /*
- * the order here is important: the stopword list is normalized with the
- * above!
- */
- return new TokenStreamComponents(source, new StopFilter(matchVersion, result, stopwords));
- }
-
- /**
- * Wraps the Reader with {@link PersianCharFilter}
- */
- @Override
- protected Reader initReader(Reader reader) {
- return matchVersion.onOrAfter(Version.LUCENE_31) ?
- new PersianCharFilter(CharReader.get(reader)) :
- reader;
- }
-}
fnp / pylucene.git / blobdiff