Lucene example source code file (TestCompoundWordTokenFilter.java)

This example Lucene source code file (TestCompoundWordTokenFilter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Lucene tags/keywords

bas, bil, dictionarycompoundwordtokenfilter, exception, glas, hyphenationcompoundwordtokenfilter, hyphenationcompoundwordtokenfilter, io, mocktokenizer, mocktokenizer, rindfleisch, sax, string, string, stringreader, stringreader

The Lucene TestCompoundWordTokenFilter.java source code

package org.apache.lucene.analysis.compound;

/**
 * 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.StringReader;
import org.xml.sax.InputSource;

import org.apache.lucene.analysis.BaseTokenStreamTestCase;
import org.apache.lucene.analysis.MockTokenizer;
import org.apache.lucene.analysis.Tokenizer;
import org.apache.lucene.analysis.WhitespaceTokenizer;
import org.apache.lucene.analysis.compound.hyphenation.HyphenationTree;
import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;

public class TestCompoundWordTokenFilter extends BaseTokenStreamTestCase {
  public void testHyphenationCompoundWordsDA() throws Exception {
    String[] dict = { "læse", "hest" };

    InputSource is = new InputSource(getClass().getResource("da_UTF8.xml").toExternalForm());
    HyphenationTree hyphenator = HyphenationCompoundWordTokenFilter
        .getHyphenationTree(is);

    HyphenationCompoundWordTokenFilter tf = new HyphenationCompoundWordTokenFilter(TEST_VERSION_CURRENT, 
        new MockTokenizer(new StringReader("min veninde som er lidt af en læsehest"), MockTokenizer.WHITESPACE, false), 
        hyphenator,
        dict, CompoundWordTokenFilterBase.DEFAULT_MIN_WORD_SIZE,
        CompoundWordTokenFilterBase.DEFAULT_MIN_SUBWORD_SIZE,
        CompoundWordTokenFilterBase.DEFAULT_MAX_SUBWORD_SIZE, false);
    assertTokenStreamContents(tf, 
        new String[] { "min", "veninde", "som", "er", "lidt", "af", "en", "læsehest", "læse", "hest" },
        new int[] { 1, 1, 1, 1, 1, 1, 1, 1, 0, 0 }
    );
  }

  public void testHyphenationCompoundWordsDELongestMatch() throws Exception {
    String[] dict = { "basketball", "basket", "ball", "kurv" };

    InputSource is = new InputSource(getClass().getResource("da_UTF8.xml").toExternalForm());
    HyphenationTree hyphenator = HyphenationCompoundWordTokenFilter
        .getHyphenationTree(is);

    // the word basket will not be added due to the longest match option
    HyphenationCompoundWordTokenFilter tf = new HyphenationCompoundWordTokenFilter(TEST_VERSION_CURRENT, 
        new MockTokenizer(new StringReader("basketballkurv"), MockTokenizer.WHITESPACE, false), 
        hyphenator, dict,
        CompoundWordTokenFilterBase.DEFAULT_MIN_WORD_SIZE,
        CompoundWordTokenFilterBase.DEFAULT_MIN_SUBWORD_SIZE, 40, true);
    assertTokenStreamContents(tf, 
        new String[] { "basketballkurv", "basketball", "ball", "kurv" },
        new int[] { 1, 0, 0, 0 }
    );

  }

  /**
   * With hyphenation-only, you can get a lot of nonsense tokens.
   * This can be controlled with the min/max subword size.
   */
  public void testHyphenationOnly() throws Exception {
    InputSource is = new InputSource(getClass().getResource("da_UTF8.xml").toExternalForm());
    HyphenationTree hyphenator = HyphenationCompoundWordTokenFilter
        .getHyphenationTree(is);
    
    HyphenationCompoundWordTokenFilter tf = new HyphenationCompoundWordTokenFilter(
        TEST_VERSION_CURRENT,
        new MockTokenizer(new StringReader("basketballkurv"), MockTokenizer.WHITESPACE, false),
        hyphenator,
        CompoundWordTokenFilterBase.DEFAULT_MIN_WORD_SIZE,
        2, 4);
    
    // min=2, max=4
    assertTokenStreamContents(tf,
        new String[] { "basketballkurv", "ba", "sket", "bal", "ball", "kurv" }
    );
    
    tf = new HyphenationCompoundWordTokenFilter(
        TEST_VERSION_CURRENT,
        new MockTokenizer(new StringReader("basketballkurv"), MockTokenizer.WHITESPACE, false),
        hyphenator,
        CompoundWordTokenFilterBase.DEFAULT_MIN_WORD_SIZE,
        4, 6);
    
    // min=4, max=6
    assertTokenStreamContents(tf,
        new String[] { "basketballkurv", "basket", "sket", "ball", "lkurv", "kurv" }
    );
    
    tf = new HyphenationCompoundWordTokenFilter(
        TEST_VERSION_CURRENT,
        new MockTokenizer(new StringReader("basketballkurv"), MockTokenizer.WHITESPACE, false),
        hyphenator,
        CompoundWordTokenFilterBase.DEFAULT_MIN_WORD_SIZE,
        4, 10);
    
    // min=4, max=10
    assertTokenStreamContents(tf,
        new String[] { "basketballkurv", "basket", "basketbal", "basketball", "sket", 
                       "sketbal", "sketball", "ball", "ballkurv", "lkurv", "kurv" }
    );
    
  }

  public void testDumbCompoundWordsSE() throws Exception {
    String[] dict = { "Bil", "Dörr", "Motor", "Tak", "Borr", "Slag", "Hammar",
        "Pelar", "Glas", "Ögon", "Fodral", "Bas", "Fiol", "Makare", "Gesäll",
        "Sko", "Vind", "Rute", "Torkare", "Blad" };

    DictionaryCompoundWordTokenFilter tf = new DictionaryCompoundWordTokenFilter(TEST_VERSION_CURRENT, 
        new MockTokenizer( 
            new StringReader(
                "Bildörr Bilmotor Biltak Slagborr Hammarborr Pelarborr Glasögonfodral Basfiolsfodral Basfiolsfodralmakaregesäll Skomakare Vindrutetorkare Vindrutetorkarblad abba"),
            MockTokenizer.WHITESPACE, false),
        dict);

    assertTokenStreamContents(tf, new String[] { "Bildörr", "Bil", "dörr", "Bilmotor",
        "Bil", "motor", "Biltak", "Bil", "tak", "Slagborr", "Slag", "borr",
        "Hammarborr", "Hammar", "borr", "Pelarborr", "Pelar", "borr",
        "Glasögonfodral", "Glas", "ögon", "fodral", "Basfiolsfodral", "Bas",
        "fiol", "fodral", "Basfiolsfodralmakaregesäll", "Bas", "fiol",
        "fodral", "makare", "gesäll", "Skomakare", "Sko", "makare",
        "Vindrutetorkare", "Vind", "rute", "torkare", "Vindrutetorkarblad",
        "Vind", "rute", "blad", "abba" }, new int[] { 0, 0, 3, 8, 8, 11, 17,
        17, 20, 24, 24, 28, 33, 33, 39, 44, 44, 49, 54, 54, 58, 62, 69, 69, 72,
        77, 84, 84, 87, 92, 98, 104, 111, 111, 114, 121, 121, 125, 129, 137,
        137, 141, 151, 156 }, new int[] { 7, 3, 7, 16, 11, 16, 23, 20, 23, 32,
        28, 32, 43, 39, 43, 53, 49, 53, 68, 58, 62, 68, 83, 72, 76, 83, 110,
        87, 91, 98, 104, 110, 120, 114, 120, 136, 125, 129, 136, 155, 141, 145,
        155, 160 }, new int[] { 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1, 0, 0, 1,
        0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 1,
        0, 0, 0, 1 });
  }

  public void testDumbCompoundWordsSELongestMatch() throws Exception {
    String[] dict = { "Bil", "Dörr", "Motor", "Tak", "Borr", "Slag", "Hammar",
        "Pelar", "Glas", "Ögon", "Fodral", "Bas", "Fiols", "Makare", "Gesäll",
        "Sko", "Vind", "Rute", "Torkare", "Blad", "Fiolsfodral" };

    DictionaryCompoundWordTokenFilter tf = new DictionaryCompoundWordTokenFilter(TEST_VERSION_CURRENT, 
        new MockTokenizer(new StringReader("Basfiolsfodralmakaregesäll"), MockTokenizer.WHITESPACE, false),
        dict, CompoundWordTokenFilterBase.DEFAULT_MIN_WORD_SIZE,
        CompoundWordTokenFilterBase.DEFAULT_MIN_SUBWORD_SIZE,
        CompoundWordTokenFilterBase.DEFAULT_MAX_SUBWORD_SIZE, true);

    assertTokenStreamContents(tf, new String[] { "Basfiolsfodralmakaregesäll", "Bas",
        "fiolsfodral", "fodral", "makare", "gesäll" }, new int[] { 0, 0, 3, 8,
        14, 20 }, new int[] { 26, 3, 14, 14, 20, 26 }, new int[] { 1, 0, 0, 0,
        0, 0 });
  }
  
  public void testReset() throws Exception {
    String[] dict = { "Rind", "Fleisch", "Draht", "Schere", "Gesetz",
        "Aufgabe", "Überwachung" };

    Tokenizer wsTokenizer = new WhitespaceTokenizer(TEST_VERSION_CURRENT, new StringReader(
        "Rindfleischüberwachungsgesetz"));
    DictionaryCompoundWordTokenFilter tf = new DictionaryCompoundWordTokenFilter(TEST_VERSION_CURRENT, 
        wsTokenizer, dict,
        CompoundWordTokenFilterBase.DEFAULT_MIN_WORD_SIZE,
        CompoundWordTokenFilterBase.DEFAULT_MIN_SUBWORD_SIZE,
        CompoundWordTokenFilterBase.DEFAULT_MAX_SUBWORD_SIZE, false);
    
    CharTermAttribute termAtt = tf.getAttribute(CharTermAttribute.class);
    assertTrue(tf.incrementToken());
    assertEquals("Rindfleischüberwachungsgesetz", termAtt.toString());
    assertTrue(tf.incrementToken());
    assertEquals("Rind", termAtt.toString());
    wsTokenizer.reset(new StringReader("Rindfleischüberwachungsgesetz"));
    tf.reset();
    assertTrue(tf.incrementToken());
    assertEquals("Rindfleischüberwachungsgesetz", termAtt.toString());
  }

}