diff --git a/lucene/CHANGES.txt b/lucene/CHANGES.txt index 61416ef1f2f..c05942fdeb5 100644 --- a/lucene/CHANGES.txt +++ b/lucene/CHANGES.txt @@ -790,6 +790,9 @@ New Features input mapping to it) for FSTs that have strictly monotonic long outputs (such as an ord). (Mike McCandless) +* LUCENE-3121: Add TypeTokenFilter that filters tokens based on + their TypeAttribute. (Tommaso Teofili via Uwe Schindler) + Bug fixes * LUCENE-3595: Fixed FieldCacheRangeFilter and FieldCacheTermsFilter diff --git a/modules/analysis/common/src/java/org/apache/lucene/analysis/core/TypeTokenFilter.java b/modules/analysis/common/src/java/org/apache/lucene/analysis/core/TypeTokenFilter.java new file mode 100644 index 00000000000..16d786f0475 --- /dev/null +++ b/modules/analysis/common/src/java/org/apache/lucene/analysis/core/TypeTokenFilter.java @@ -0,0 +1,47 @@ +package org.apache.lucene.analysis.core; + +/* + * 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.tokenattributes.TypeAttribute; +import org.apache.lucene.analysis.util.FilteringTokenFilter; + +import java.io.IOException; +import java.util.Set; + +/** + * Removes tokens whose types appear in a set of blocked types from a token stream. + */ +public final class TypeTokenFilter extends FilteringTokenFilter { + + private final Set stopTypes; + private final TypeAttribute typeAttribute = addAttribute(TypeAttribute.class); + + public TypeTokenFilter(boolean enablePositionIncrements, TokenStream input, Set stopTypes) { + super(enablePositionIncrements, input); + this.stopTypes = stopTypes; + } + + /** + * Returns the next input Token whose typeAttribute.type() is not a stop type. + */ + @Override + protected boolean accept() throws IOException { + return !stopTypes.contains(typeAttribute.type()); + } +} diff --git a/modules/analysis/common/src/test/org/apache/lucene/analysis/core/TestTypeTokenFilter.java b/modules/analysis/common/src/test/org/apache/lucene/analysis/core/TestTypeTokenFilter.java new file mode 100644 index 00000000000..36b547c4c65 --- /dev/null +++ b/modules/analysis/common/src/test/org/apache/lucene/analysis/core/TestTypeTokenFilter.java @@ -0,0 +1,92 @@ +package org.apache.lucene.analysis.core; + +/* + * 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.BaseTokenStreamTestCase; +import org.apache.lucene.analysis.TokenStream; +import org.apache.lucene.analysis.standard.StandardTokenizer; +import org.apache.lucene.analysis.tokenattributes.CharTermAttribute; +import org.apache.lucene.analysis.tokenattributes.PositionIncrementAttribute; +import org.apache.lucene.analysis.tokenattributes.TypeAttribute; +import org.apache.lucene.util.English; + +import java.io.IOException; +import java.io.StringReader; +import java.util.Set; + + +public class TestTypeTokenFilter extends BaseTokenStreamTestCase { + + public void testTypeFilter() throws IOException { + StringReader reader = new StringReader("121 is palindrome, while 123 is not"); + Set stopTypes = asSet(""); + TokenStream stream = new TypeTokenFilter(true, new StandardTokenizer(TEST_VERSION_CURRENT, reader), stopTypes); + assertTokenStreamContents(stream, new String[]{"is", "palindrome", "while", "is", "not"}); + } + + /** + * Test Position increments applied by TypeTokenFilter with and without enabling this option. + */ + public void testStopPositons() throws IOException { + StringBuilder sb = new StringBuilder(); + for (int i = 10; i < 20; i++) { + if (i % 3 != 0) { + sb.append(i).append(" "); + } else { + String w = English.intToEnglish(i).trim(); + sb.append(w).append(" "); + } + } + log(sb.toString()); + String stopTypes[] = new String[]{""}; + Set stopSet = asSet(stopTypes); + + // with increments + StringReader reader = new StringReader(sb.toString()); + TypeTokenFilter typeTokenFilter = new TypeTokenFilter(true, new StandardTokenizer(TEST_VERSION_CURRENT, reader), stopSet); + testPositons(typeTokenFilter); + + // without increments + reader = new StringReader(sb.toString()); + typeTokenFilter = new TypeTokenFilter(false, new StandardTokenizer(TEST_VERSION_CURRENT, reader), stopSet); + testPositons(typeTokenFilter); + + } + + private void testPositons(TypeTokenFilter stpf) throws IOException { + TypeAttribute typeAtt = stpf.getAttribute(TypeAttribute.class); + CharTermAttribute termAttribute = stpf.getAttribute(CharTermAttribute.class); + PositionIncrementAttribute posIncrAtt = stpf.getAttribute(PositionIncrementAttribute.class); + stpf.reset(); + boolean enablePositionIncrements = stpf.getEnablePositionIncrements(); + while (stpf.incrementToken()) { + log("Token: " + termAttribute.toString() + ": " + typeAtt.type() + " - " + posIncrAtt.getPositionIncrement()); + assertEquals("if position increment is enabled the positionIncrementAttribute value should be 3, otherwise 1", + posIncrAtt.getPositionIncrement(), enablePositionIncrements ? 3 : 1); + } + stpf.end(); + stpf.close(); + } + + // print debug info depending on VERBOSE + private static void log(String s) { + if (VERBOSE) { + System.out.println(s); + } + } +}