Lucene example source code file (TestSnowballVocab.java)

This example Lucene source code file (TestSnowballVocab.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

dutch, io, ioexception, ioexception, kp, reader, reader, reusableanalyzerbase, spanish, string, string, swedish, testsnowballvocab, tokenstreamcomponents, tokenstreamcomponents

The Lucene TestSnowballVocab.java source code

package org.apache.lucene.analysis.snowball;

/**
 * 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 org.apache.lucene.analysis.KeywordTokenizer;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.Tokenizer;
import org.apache.lucene.analysis.ReusableAnalyzerBase;
import org.apache.lucene.util.LuceneTestCase;

import static org.apache.lucene.analysis.VocabularyAssert.*;

/**
 * Test the snowball filters against the snowball data tests
 */
public class TestSnowballVocab extends LuceneTestCase {
  /**
   * Run all languages against their snowball vocabulary tests.
   */
  public void testStemmers() throws IOException {
    assertCorrectOutput("Danish", "danish");
    assertCorrectOutput("Dutch", "dutch");
    assertCorrectOutput("English", "english");
    // disabled due to snowball java code generation bug: 
    // see http://article.gmane.org/gmane.comp.search.snowball/1139
    // assertCorrectOutput("Finnish", "finnish");
    assertCorrectOutput("French", "french");
    assertCorrectOutput("German", "german");
    assertCorrectOutput("German2", "german2");
    assertCorrectOutput("Hungarian", "hungarian");
    assertCorrectOutput("Italian", "italian");
    assertCorrectOutput("Kp", "kraaij_pohlmann");
    // disabled due to snowball java code generation bug: 
    // see http://article.gmane.org/gmane.comp.search.snowball/1139
    // assertCorrectOutput("Lovins", "lovins");
    assertCorrectOutput("Norwegian", "norwegian");
    assertCorrectOutput("Porter", "porter");
    assertCorrectOutput("Portuguese", "portuguese");
    assertCorrectOutput("Romanian", "romanian");
    assertCorrectOutput("Russian", "russian");
    assertCorrectOutput("Spanish", "spanish");
    assertCorrectOutput("Swedish", "swedish");
    assertCorrectOutput("Turkish", "turkish");
  }
    
  /**
   * For the supplied language, run the stemmer against all strings in voc.txt
   * The output should be the same as the string in output.txt
   */
  private void assertCorrectOutput(final String snowballLanguage, String dataDirectory)
      throws IOException {
    if (VERBOSE) System.out.println("checking snowball language: " + snowballLanguage);
    
    Analyzer a = new ReusableAnalyzerBase() {
      @Override
      protected TokenStreamComponents createComponents(String fieldName,
          Reader reader) {
        Tokenizer t = new KeywordTokenizer(reader);
        return new TokenStreamComponents(t, new SnowballFilter(t, snowballLanguage));
      }  
    };
    
    assertVocabulary(a, getDataFile("TestSnowballVocabData.zip"), 
        dataDirectory + "/voc.txt", dataDirectory + "/output.txt");
  }
}