From 7e20a9f80a9a1d0d439fe92e5d90c82ecfdd2d62 Mon Sep 17 00:00:00 2001 From: belevian Date: Fri, 8 Jul 2011 15:17:36 +0200 Subject: [PATCH] Analysis: expose Lucene PatternReplaceFilter. --- .../pattern/PatternReplaceFilter.java | 85 +++++++++++++++++++ .../index/analysis/AnalysisModule.java | 1 + .../PatternReplaceTokenFilterFactory.java | 65 ++++++++++++++ 3 files changed, 151 insertions(+) create mode 100644 modules/elasticsearch/src/main/java/org/apache/lucene/analysis/pattern/PatternReplaceFilter.java create mode 100644 modules/elasticsearch/src/main/java/org/elasticsearch/index/analysis/PatternReplaceTokenFilterFactory.java diff --git a/modules/elasticsearch/src/main/java/org/apache/lucene/analysis/pattern/PatternReplaceFilter.java b/modules/elasticsearch/src/main/java/org/apache/lucene/analysis/pattern/PatternReplaceFilter.java new file mode 100644 index 00000000000..9ddc816e6b7 --- /dev/null +++ b/modules/elasticsearch/src/main/java/org/apache/lucene/analysis/pattern/PatternReplaceFilter.java @@ -0,0 +1,85 @@ +/* + * Licensed to Elastic Search and Shay Banon under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. Elastic Search 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. + */ + +package org.apache.lucene.analysis.pattern; + +import org.apache.lucene.analysis.TokenFilter; +import org.apache.lucene.analysis.TokenStream; +import org.apache.lucene.analysis.tokenattributes.CharTermAttribute; + +import java.util.regex.Pattern; +import java.util.regex.Matcher; +import java.io.IOException; + +/** + * A TokenFilter which applies a Pattern to each token in the stream, + * replacing match occurances with the specified replacement string. + * + *

+ * Note: Depending on the input and the pattern used and the input + * TokenStream, this TokenFilter may produce Tokens whose text is the empty + * string. + *

+ * + * @see Pattern + */ +public final class PatternReplaceFilter extends TokenFilter { + private final Pattern p; + private final String replacement; + private final boolean all; + private final CharTermAttribute termAtt = addAttribute(CharTermAttribute.class); + private final Matcher m; + + /** + * Constructs an instance to replace either the first, or all occurances + * + * @param in the TokenStream to process + * @param p the patterm to apply to each Token + * @param replacement the "replacement string" to substitute, if null a + * blank string will be used. Note that this is not the literal + * string that will be used, '$' and '\' have special meaning. + * @param all if true, all matches will be replaced otherwise just the first match. + * @see Matcher#quoteReplacement + */ + public PatternReplaceFilter(TokenStream in, + Pattern p, + String replacement, + boolean all) { + super(in); + this.p=p; + this.replacement = (null == replacement) ? "" : replacement; + this.all=all; + this.m = p.matcher(termAtt); + } + + @Override + public boolean incrementToken() throws IOException { + if (!input.incrementToken()) return false; + + m.reset(); + if (m.find()) { + // replaceAll/replaceFirst will reset() this previous find. + String transformed = all ? m.replaceAll(replacement) : m.replaceFirst(replacement); + termAtt.setEmpty().append(transformed); + } + + return true; + } + +} diff --git a/modules/elasticsearch/src/main/java/org/elasticsearch/index/analysis/AnalysisModule.java b/modules/elasticsearch/src/main/java/org/elasticsearch/index/analysis/AnalysisModule.java index 88a318b07ef..da646261b93 100644 --- a/modules/elasticsearch/src/main/java/org/elasticsearch/index/analysis/AnalysisModule.java +++ b/modules/elasticsearch/src/main/java/org/elasticsearch/index/analysis/AnalysisModule.java @@ -377,6 +377,7 @@ public class AnalysisModule extends AbstractModule { tokenFiltersBindings.processTokenFilter("synonym", SynonymTokenFilterFactory.class); tokenFiltersBindings.processTokenFilter("elision", ElisionTokenFilterFactory.class); + tokenFiltersBindings.processTokenFilter("pattern_replace", PatternReplaceTokenFilterFactory.class); tokenFiltersBindings.processTokenFilter("phonetic", PhoneticTokenFilterFactory.class); tokenFiltersBindings.processTokenFilter("dictionary_decompounder", DictionaryCompoundWordTokenFilterFactory.class); tokenFiltersBindings.processTokenFilter("hypennation_decompounder", HyphenationCompoundWordTokenFilterFactory.class); diff --git a/modules/elasticsearch/src/main/java/org/elasticsearch/index/analysis/PatternReplaceTokenFilterFactory.java b/modules/elasticsearch/src/main/java/org/elasticsearch/index/analysis/PatternReplaceTokenFilterFactory.java new file mode 100644 index 00000000000..3da149ee8e7 --- /dev/null +++ b/modules/elasticsearch/src/main/java/org/elasticsearch/index/analysis/PatternReplaceTokenFilterFactory.java @@ -0,0 +1,65 @@ +/* + * Licensed to Elastic Search and Shay Banon under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. Elastic Search 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. + */ + +package org.elasticsearch.index.analysis; + +import org.apache.lucene.analysis.TokenStream; +import org.apache.lucene.analysis.pattern.PatternReplaceFilter; +import org.elasticsearch.ElasticSearchIllegalArgumentException; +import org.elasticsearch.common.inject.Inject; +import org.elasticsearch.common.inject.assistedinject.Assisted; +import org.elasticsearch.common.regex.Regex; +import org.elasticsearch.common.settings.Settings; +import org.elasticsearch.index.Index; +import org.elasticsearch.index.settings.IndexSettings; + +import java.io.IOException; +import java.io.Reader; +import java.util.regex.Pattern; + +public class PatternReplaceTokenFilterFactory extends AbstractTokenFilterFactory { + + private final Pattern pattern; + private final String replacement; + private final boolean all; + + @Inject public PatternReplaceTokenFilterFactory(Index index, @IndexSettings Settings indexSettings, @Assisted String name, @Assisted Settings settings) { + super(index, indexSettings, name, settings); + + String sPattern = settings.get("pattern", ""); + if (sPattern == null) { + throw new ElasticSearchIllegalArgumentException("pattern is missing for [" + name + "] token filter of type 'pattern_replace'"); + } + + this.pattern = Regex.compile(sPattern, settings.get("flags")); + + String sReplacement = settings.get("replacement", ""); + if (sReplacement == null) { + throw new ElasticSearchIllegalArgumentException("replacement is missing for [" + name + "] token filter of type 'pattern_replace'"); + } + + this.replacement = sReplacement; + + this.all = settings.getAsBoolean("all", true); + } + + @Override public TokenStream create(TokenStream tokenStream) { + return new PatternReplaceFilter(tokenStream, pattern, replacement, all); + } +} \ No newline at end of file