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Lucene example source code file (TestFilterIndexReader.java)

This example Lucene source code file (TestFilterIndexReader.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, document, indexwriter, io, ioexception, ioexception, num_docs, override, override, termenum, termpositions, testreader, testtermenum, testtermenum, testtermpositions

The Lucene TestFilterIndexReader.java source code

package org.apache.lucene.index;

/**
 * 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.util.LuceneTestCase;
import junit.framework.TestSuite;
import junit.textui.TestRunner;

import org.apache.lucene.analysis.MockAnalyzer;
import org.apache.lucene.store.Directory;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;

import java.io.IOException;

public class TestFilterIndexReader extends LuceneTestCase {

  private static class TestReader extends FilterIndexReader {

     /** Filter that only permits terms containing 'e'.*/
    private static class TestTermEnum extends FilterTermEnum {
      public TestTermEnum(TermEnum termEnum) {
        super(termEnum);
      }

      /** Scan for terms containing the letter 'e'.*/
      @Override
      public boolean next() throws IOException {
        while (in.next()) {
          if (in.term().text().indexOf('e') != -1)
            return true;
        }
        return false;
      }
    }
    
    /** Filter that only returns odd numbered documents. */
    private static class TestTermPositions extends FilterTermPositions {
      public TestTermPositions(TermPositions in) {
        super(in);
      }

      /** Scan for odd numbered documents. */
      @Override
      public boolean next() throws IOException {
        while (in.next()) {
          if ((in.doc() % 2) == 1)
            return true;
        }
        return false;
      }
    }
    
    public TestReader(IndexReader reader) {
      super(reader);
    }

    /** Filter terms with TestTermEnum. */
    @Override
    public TermEnum terms() throws IOException {
      return new TestTermEnum(in.terms());
    }

    /** Filter positions with TestTermPositions. */
    @Override
    public TermPositions termPositions() throws IOException {
      return new TestTermPositions(in.termPositions());
    }
  }


  /** Main for running test case by itself. */
  public static void main(String args[]) {
    TestRunner.run (new TestSuite(TestIndexReader.class));
  }
    
  /**
   * Tests the IndexReader.getFieldNames implementation
   * @throws Exception on error
   */
  public void testFilterIndexReader() throws Exception {
    Directory directory = newDirectory();
    IndexWriter writer = new IndexWriter(directory, newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random)));

    Document d1 = new Document();
    d1.add(newField("default","one two", Field.Store.YES, Field.Index.ANALYZED));
    writer.addDocument(d1);

    Document d2 = new Document();
    d2.add(newField("default","one three", Field.Store.YES, Field.Index.ANALYZED));
    writer.addDocument(d2);

    Document d3 = new Document();
    d3.add(newField("default","two four", Field.Store.YES, Field.Index.ANALYZED));
    writer.addDocument(d3);

    writer.close();

    IndexReader reader = new TestReader(IndexReader.open(directory, true));
    TermEnum terms = reader.terms();
    while (terms.next()) {
      assertTrue(terms.term().text().indexOf('e') != -1);
    }
    terms.close();
    
    TermPositions positions = reader.termPositions(new Term("default", "one"));
    while (positions.next()) {
      assertTrue((positions.doc() % 2) == 1);
    }

    int NUM_DOCS = 3;

    TermDocs td = reader.termDocs(null);
    for(int i=0;i<NUM_DOCS;i++) {
      assertTrue(td.next());
      assertEquals(i, td.doc());
      assertEquals(1, td.freq());
    }
    td.close();
    reader.close();
    directory.close();
  }
}

Other Lucene examples (source code examples)

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

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