alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Lucene example source code file (SimpleFragmentsBuilderTest.java)

This example Lucene source code file (SimpleFragmentsBuilderTest.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

document, exception, f, f, fieldfraglist, fieldphraselist, fieldquery, fieldquery, fieldtermstack, fieldtermstack, simplefraglistbuilder, simplefragmentsbuilder, simplefragmentsbuilder, string

The Lucene SimpleFragmentsBuilderTest.java source code

package org.apache.lucene.search.vectorhighlight;

/**
 * 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.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.Field.Index;
import org.apache.lucene.document.Field.Store;
import org.apache.lucene.document.Field.TermVector;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.highlight.SimpleHTMLEncoder;

public class SimpleFragmentsBuilderTest extends AbstractTestCase {
  
  public void test1TermIndex() throws Exception {
    FieldFragList ffl = ffl( "a", "a" );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    assertEquals( "<b>a ", sfb.createFragment( reader, 0, F, ffl ) );

    // change tags
    sfb = new SimpleFragmentsBuilder( new String[]{ "[" }, new String[]{ "]" } );
    assertEquals( "[a] ", sfb.createFragment( reader, 0, F, ffl ) );
  }
  
  public void test2Frags() throws Exception {
    FieldFragList ffl = ffl( "a", "a b b b b b b b b b b b a b a b" );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    String[] f = sfb.createFragments( reader, 0, F, ffl, 3 );
    // 3 snippets requested, but should be 2
    assertEquals( 2, f.length );
    assertEquals( "<b>a b b b b b b b b b ", f[0] );
    assertEquals( "b b <b>a b a b ", f[1] );
  }
  
  public void test3Frags() throws Exception {
    FieldFragList ffl = ffl( "a c", "a b b b b b b b b b b b a b a b b b b b c a a b b" );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    String[] f = sfb.createFragments( reader, 0, F, ffl, 3 );
    assertEquals( 3, f.length );
    assertEquals( "<b>a b b b b b b b b b ", f[0] );
    assertEquals( "b b <b>a b a b b b b b ", f[1] );
    assertEquals( "<b>c a a b b ", f[2] );
  }
  
  public void testTagsAndEncoder() throws Exception {
    FieldFragList ffl = ffl( "a", "<h1> a " );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    String[] preTags = { "[" };
    String[] postTags = { "]" };
    assertEquals( "<h1> [a] </h1> ",
        sfb.createFragment( reader, 0, F, ffl, preTags, postTags, new SimpleHTMLEncoder() ) );
  }

  private FieldFragList ffl( String queryValue, String indexValue ) throws Exception {
    make1d1fIndex( indexValue );
    Query query = paW.parse( queryValue );
    FieldQuery fq = new FieldQuery( query, true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    FieldPhraseList fpl = new FieldPhraseList( stack, fq );
    return new SimpleFragListBuilder().createFieldFragList( fpl, 20 );
  }
  
  public void test1PhraseShortMV() throws Exception {
    makeIndexShortMV();

    FieldQuery fq = new FieldQuery( tq( "d" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    FieldPhraseList fpl = new FieldPhraseList( stack, fq );
    SimpleFragListBuilder sflb = new SimpleFragListBuilder();
    FieldFragList ffl = sflb.createFieldFragList( fpl, 100 );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    assertEquals( " b c  <b>d e ", sfb.createFragment( reader, 0, F, ffl ) );
  }
  
  public void test1PhraseLongMV() throws Exception {
    makeIndexLongMV();

    FieldQuery fq = new FieldQuery( pqF( "search", "engines" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    FieldPhraseList fpl = new FieldPhraseList( stack, fq );
    SimpleFragListBuilder sflb = new SimpleFragListBuilder();
    FieldFragList ffl = sflb.createFieldFragList( fpl, 100 );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    assertEquals( " most <b>search engines use only one of these methods. Even the search engines that says they can use t",
        sfb.createFragment( reader, 0, F, ffl ) );
  }

  public void test1PhraseLongMVB() throws Exception {
    makeIndexLongMVB();

    FieldQuery fq = new FieldQuery( pqF( "sp", "pe", "ee", "ed" ), true, true ); // "speed" -(2gram)-> "sp","pe","ee","ed"
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    FieldPhraseList fpl = new FieldPhraseList( stack, fq );
    SimpleFragListBuilder sflb = new SimpleFragListBuilder();
    FieldFragList ffl = sflb.createFieldFragList( fpl, 100 );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    assertEquals( "ssing <b>speed, the ", sfb.createFragment( reader, 0, F, ffl ) );
  }
  
  public void testUnstoredField() throws Exception {
    makeUnstoredIndex();

    FieldQuery fq = new FieldQuery( tq( "aaa" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    FieldPhraseList fpl = new FieldPhraseList( stack, fq );
    SimpleFragListBuilder sflb = new SimpleFragListBuilder();
    FieldFragList ffl = sflb.createFieldFragList( fpl, 100 );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    assertNull( sfb.createFragment( reader, 0, F, ffl ) );
  }
  
  protected void makeUnstoredIndex() throws Exception {
    IndexWriter writer = new IndexWriter(dir, new IndexWriterConfig(
        TEST_VERSION_CURRENT, analyzerW).setOpenMode(OpenMode.CREATE));
    Document doc = new Document();
    doc.add( new Field( F, "aaa", Store.NO, Index.ANALYZED, TermVector.WITH_POSITIONS_OFFSETS ) );
    writer.addDocument( doc );
    writer.close();
    if (reader != null) reader.close();
    reader = IndexReader.open( dir, true );
  }
  
  public void test1StrMV() throws Exception {
    makeIndexStrMV();

    FieldQuery fq = new FieldQuery( tq( "defg" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    FieldPhraseList fpl = new FieldPhraseList( stack, fq );
    SimpleFragListBuilder sflb = new SimpleFragListBuilder();
    FieldFragList ffl = sflb.createFieldFragList( fpl, 100 );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    // '/' separator doesn't effect the snippet because of NOT_ANALYZED field
    sfb.setMultiValuedSeparator( '/' );
    assertEquals( "abc<b>defghijkl", sfb.createFragment( reader, 0, F, ffl ) );
  }
  
  public void testMVSeparator() throws Exception {
    makeIndexShortMV();

    FieldQuery fq = new FieldQuery( tq( "d" ), true, true );
    FieldTermStack stack = new FieldTermStack( reader, 0, F, fq );
    FieldPhraseList fpl = new FieldPhraseList( stack, fq );
    SimpleFragListBuilder sflb = new SimpleFragListBuilder();
    FieldFragList ffl = sflb.createFieldFragList( fpl, 100 );
    SimpleFragmentsBuilder sfb = new SimpleFragmentsBuilder();
    sfb.setMultiValuedSeparator( '/' );
    assertEquals( " b c//<b>d e/", sfb.createFragment( reader, 0, F, ffl ) );
  }
}

Other Lucene examples (source code examples)

Here is a short list of links related to this Lucene SimpleFragmentsBuilderTest.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.