--- /dev/null
+package org.apache.lucene.analysis.ru;
+
+/**
+ * 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.Arrays;
+import java.util.Map;
+import java.util.Set;
+
+import org.apache.lucene.analysis.Analyzer;
+import org.apache.lucene.analysis.CharArraySet;
+import org.apache.lucene.analysis.LowerCaseFilter;
+import org.apache.lucene.analysis.snowball.SnowballFilter;
+import org.apache.lucene.analysis.standard.StandardFilter;
+import org.apache.lucene.analysis.standard.StandardTokenizer;
+import org.apache.lucene.analysis.KeywordMarkerFilter;
+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.WordlistLoader;
+import org.apache.lucene.util.IOUtils;
+import org.apache.lucene.util.Version;
+
+/**
+ * {@link Analyzer} for Russian language.
+ * <p>
+ * Supports an external list of stopwords (words that
+ * will not be indexed at all).
+ * A default set of stopwords is used unless an alternative list is specified.
+ * </p>
+ * <a name="version"/>
+ * <p>You must specify the required {@link Version}
+ * compatibility when creating RussianAnalyzer:
+ * <ul>
+ * <li> As of 3.1, StandardTokenizer is used, Snowball stemming is done with
+ * SnowballFilter, and Snowball stopwords are used by default.
+ * </ul>
+ */
+public final class RussianAnalyzer extends StopwordAnalyzerBase
+{
+ /**
+ * List of typical Russian stopwords. (for backwards compatibility)
+ * @deprecated Remove this for LUCENE 5.0
+ */
+ @Deprecated
+ private static final String[] RUSSIAN_STOP_WORDS_30 = {
+ "а", "без", "более", "бы", "был", "была", "были", "было", "быть", "в",
+ "вам", "вас", "весь", "во", "вот", "все", "всего", "всех", "вы", "где",
+ "да", "даже", "для", "до", "его", "ее", "ей", "ею", "если", "есть",
+ "еще", "же", "за", "здесь", "и", "из", "или", "им", "их", "к", "как",
+ "ко", "когда", "кто", "ли", "либо", "мне", "может", "мы", "на", "надо",
+ "наш", "не", "него", "нее", "нет", "ни", "них", "но", "ну", "о", "об",
+ "однако", "он", "она", "они", "оно", "от", "очень", "по", "под", "при",
+ "с", "со", "так", "также", "такой", "там", "те", "тем", "то", "того",
+ "тоже", "той", "только", "том", "ты", "у", "уже", "хотя", "чего", "чей",
+ "чем", "что", "чтобы", "чье", "чья", "эта", "эти", "это", "я"
+ };
+
+ /** File containing default Russian stopwords. */
+ public final static String DEFAULT_STOPWORD_FILE = "russian_stop.txt";
+
+ private static class DefaultSetHolder {
+ /** @deprecated remove this for Lucene 5.0 */
+ @Deprecated
+ static final Set<?> DEFAULT_STOP_SET_30 = CharArraySet
+ .unmodifiableSet(new CharArraySet(Version.LUCENE_CURRENT,
+ Arrays.asList(RUSSIAN_STOP_WORDS_30), false));
+ static final Set<?> DEFAULT_STOP_SET;
+
+ static {
+ try {
+ DEFAULT_STOP_SET = WordlistLoader.getSnowballWordSet(IOUtils.getDecodingReader(SnowballFilter.class,
+ DEFAULT_STOPWORD_FILE, IOUtils.CHARSET_UTF_8), Version.LUCENE_CURRENT);
+ } 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", ex);
+ }
+ }
+ }
+
+ private final Set<?> stemExclusionSet;
+
+ /**
+ * 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;
+ }
+
+ public RussianAnalyzer(Version matchVersion) {
+ this(matchVersion,
+ matchVersion.onOrAfter(Version.LUCENE_31) ? DefaultSetHolder.DEFAULT_STOP_SET
+ : DefaultSetHolder.DEFAULT_STOP_SET_30);
+ }
+
+ /**
+ * Builds an analyzer with the given stop words.
+ * @deprecated use {@link #RussianAnalyzer(Version, Set)} instead
+ */
+ @Deprecated
+ public RussianAnalyzer(Version matchVersion, String... stopwords) {
+ this(matchVersion, StopFilter.makeStopSet(matchVersion, stopwords));
+ }
+
+ /**
+ * Builds an analyzer with the given stop words
+ *
+ * @param matchVersion
+ * lucene compatibility version
+ * @param stopwords
+ * a stopword set
+ */
+ public RussianAnalyzer(Version matchVersion, Set<?> stopwords){
+ this(matchVersion, stopwords, CharArraySet.EMPTY_SET);
+ }
+
+ /**
+ * Builds an analyzer with the given stop words
+ *
+ * @param matchVersion
+ * lucene compatibility version
+ * @param stopwords
+ * a stopword set
+ * @param stemExclusionSet a set of words not to be stemmed
+ */
+ public RussianAnalyzer(Version matchVersion, Set<?> stopwords, Set<?> stemExclusionSet){
+ super(matchVersion, stopwords);
+ this.stemExclusionSet = CharArraySet.unmodifiableSet(CharArraySet.copy(matchVersion, stemExclusionSet));
+ }
+
+
+ /**
+ * Builds an analyzer with the given stop words.
+ * TODO: create a Set version of this ctor
+ * @deprecated use {@link #RussianAnalyzer(Version, Set)} instead
+ */
+ @Deprecated
+ public RussianAnalyzer(Version matchVersion, Map<?,?> stopwords)
+ {
+ this(matchVersion, stopwords.keySet());
+ }
+
+ /**
+ * 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 StandardFilter}, {@link LowerCaseFilter}, {@link StopFilter}
+ * , {@link KeywordMarkerFilter} if a stem exclusion set is
+ * provided, and {@link SnowballFilter}
+ */
+ @Override
+ protected TokenStreamComponents createComponents(String fieldName,
+ Reader reader) {
+ if (matchVersion.onOrAfter(Version.LUCENE_31)) {
+ 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);
+ result = new SnowballFilter(result, new org.tartarus.snowball.ext.RussianStemmer());
+ return new TokenStreamComponents(source, result);
+ } else {
+ final Tokenizer source = new RussianLetterTokenizer(matchVersion, reader);
+ TokenStream result = new LowerCaseFilter(matchVersion, source);
+ result = new StopFilter(matchVersion, result, stopwords);
+ if (!stemExclusionSet.isEmpty()) result = new KeywordMarkerFilter(
+ result, stemExclusionSet);
+ return new TokenStreamComponents(source, new RussianStemFilter(result));
+ }
+ }
+}
fnp / pylucene.git / blobdiff