Lucene example source code file (TestNearSpansOrdered.java)

This example Lucene source code file (TestNearSpansOrdered.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, exception, field, override, scorer, spannearquery, spannearquery, spans, spans, spantermquery, string, string, term

The Lucene TestNearSpansOrdered.java source code

package org.apache.lucene.search.spans;

/**
 * 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.MockAnalyzer;

import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.RandomIndexWriter;
import org.apache.lucene.index.Term;
import org.apache.lucene.queryParser.QueryParser;
import org.apache.lucene.search.CheckHits;
import org.apache.lucene.search.Explanation;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Weight;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.store.Directory;
import org.apache.lucene.util.LuceneTestCase;

public class TestNearSpansOrdered extends LuceneTestCase {
  protected IndexSearcher searcher;
  protected Directory directory;
  protected IndexReader reader;

  public static final String FIELD = "field";
  public static final QueryParser qp =
    new QueryParser(TEST_VERSION_CURRENT, FIELD, new MockAnalyzer(random));

  @Override
  public void tearDown() throws Exception {
    searcher.close();
    reader.close();
    directory.close();
    super.tearDown();
  }
  
  @Override
  public void setUp() throws Exception {
    super.setUp();
    directory = newDirectory();
    RandomIndexWriter writer= new RandomIndexWriter(random, directory, newIndexWriterConfig(TEST_VERSION_CURRENT, new MockAnalyzer(random)).setMergePolicy(newLogMergePolicy()));
    for (int i = 0; i < docFields.length; i++) {
      Document doc = new Document();
      doc.add(newField(FIELD, docFields[i], Field.Store.NO, Field.Index.ANALYZED));
      writer.addDocument(doc);
    }
    reader = writer.getReader();
    writer.close();
    searcher = newSearcher(reader);
  }

  protected String[] docFields = {
    "w1 w2 w3 w4 w5",
    "w1 w3 w2 w3 zz",
    "w1 xx w2 yy w3",
    "w1 w3 xx w2 yy w3 zz"
  };

  protected SpanNearQuery makeQuery(String s1, String s2, String s3,
                                    int slop, boolean inOrder) {
    return new SpanNearQuery
      (new SpanQuery[] {
        new SpanTermQuery(new Term(FIELD, s1)),
        new SpanTermQuery(new Term(FIELD, s2)),
        new SpanTermQuery(new Term(FIELD, s3)) },
       slop,
       inOrder);
  }
  protected SpanNearQuery makeQuery() {
    return makeQuery("w1","w2","w3",1,true);
  }
  
  public void testSpanNearQuery() throws Exception {
    SpanNearQuery q = makeQuery();
    CheckHits.checkHits(random, q, FIELD, searcher, new int[] {0,1});
  }

  public String s(Spans span) {
    return s(span.doc(), span.start(), span.end());
  }
  public String s(int doc, int start, int end) {
    return "s(" + doc + "," + start + "," + end +")";
  }
  
  public void testNearSpansNext() throws Exception {
    SpanNearQuery q = makeQuery();
    Spans span = q.getSpans(searcher.getIndexReader());
    assertEquals(true, span.next());
    assertEquals(s(0,0,3), s(span));
    assertEquals(true, span.next());
    assertEquals(s(1,0,4), s(span));
    assertEquals(false, span.next());
  }

  /**
   * test does not imply that skipTo(doc+1) should work exactly the
   * same as next -- it's only applicable in this case since we know doc
   * does not contain more than one span
   */
  public void testNearSpansSkipToLikeNext() throws Exception {
    SpanNearQuery q = makeQuery();
    Spans span = q.getSpans(searcher.getIndexReader());
    assertEquals(true, span.skipTo(0));
    assertEquals(s(0,0,3), s(span));
    assertEquals(true, span.skipTo(1));
    assertEquals(s(1,0,4), s(span));
    assertEquals(false, span.skipTo(2));
  }
  
  public void testNearSpansNextThenSkipTo() throws Exception {
    SpanNearQuery q = makeQuery();
    Spans span = q.getSpans(searcher.getIndexReader());
    assertEquals(true, span.next());
    assertEquals(s(0,0,3), s(span));
    assertEquals(true, span.skipTo(1));
    assertEquals(s(1,0,4), s(span));
    assertEquals(false, span.next());
  }
  
  public void testNearSpansNextThenSkipPast() throws Exception {
    SpanNearQuery q = makeQuery();
    Spans span = q.getSpans(searcher.getIndexReader());
    assertEquals(true, span.next());
    assertEquals(s(0,0,3), s(span));
    assertEquals(false, span.skipTo(2));
  }
  
  public void testNearSpansSkipPast() throws Exception {
    SpanNearQuery q = makeQuery();
    Spans span = q.getSpans(searcher.getIndexReader());
    assertEquals(false, span.skipTo(2));
  }
  
  public void testNearSpansSkipTo0() throws Exception {
    SpanNearQuery q = makeQuery();
    Spans span = q.getSpans(searcher.getIndexReader());
    assertEquals(true, span.skipTo(0));
    assertEquals(s(0,0,3), s(span));
  }

  public void testNearSpansSkipTo1() throws Exception {
    SpanNearQuery q = makeQuery();
    Spans span = q.getSpans(searcher.getIndexReader());
    assertEquals(true, span.skipTo(1));
    assertEquals(s(1,0,4), s(span));
  }

  /**
   * not a direct test of NearSpans, but a demonstration of how/when
   * this causes problems
   */
  public void testSpanNearScorerSkipTo1() throws Exception {
    SpanNearQuery q = makeQuery();
    Weight w = searcher.createNormalizedWeight(q);
    Scorer s = w.scorer(searcher.getIndexReader(), true, false);
    assertEquals(1, s.advance(1));
  }
  
  /**
   * not a direct test of NearSpans, but a demonstration of how/when
   * this causes problems
   */
  public void testSpanNearScorerExplain() throws Exception {
    SpanNearQuery q = makeQuery();
    Explanation e = searcher.explain(q, 1);
    assertTrue("Scorer explanation value for doc#1 isn't positive: "
               + e.toString(),
               0.0f < e.getValue());
  }
  
}