Lucene example source code file (TestCachingSpanFilter.java)

This example Lucene source code file (TestCachingSpanFilter.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

cachingspanfilter, constantscorequery, constantscorequery, document, exception, indexreader, indexreader, io, ioexception, matchalldocsquery, matchalldocsquery, randomindexwriter, should, should, term

The Lucene TestCachingSpanFilter.java source code

package org.apache.lucene.search;

/**
 * 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 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.SerialMergeScheduler;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.spans.SpanTermQuery;
import org.apache.lucene.analysis.MockAnalyzer;
import org.apache.lucene.store.Directory;
import org.apache.lucene.util.LuceneTestCase;
import org.apache.lucene.util._TestUtil;

public class TestCachingSpanFilter extends LuceneTestCase {

  public void testEnforceDeletions() throws Exception {
    Directory dir = newDirectory();
    RandomIndexWriter writer = new RandomIndexWriter(
        random,
        dir,
        newIndexWriterConfig(random, TEST_VERSION_CURRENT, new MockAnalyzer(random)).
            setMergeScheduler(new SerialMergeScheduler()).
            // asserts below requires no unexpected merges:
            setMergePolicy(newLogMergePolicy(10))
    );

    // NOTE: cannot use writer.getReader because RIW (on
    // flipping a coin) may give us a newly opened reader,
    // but we use .reopen on this reader below and expect to
    // (must) get an NRT reader:
    IndexReader reader = IndexReader.open(writer.w, true);
    // same reason we don't wrap?
    IndexSearcher searcher = newSearcher(reader, false);

    // add a doc, refresh the reader, and check that its there
    Document doc = new Document();
    doc.add(newField("id", "1", Field.Store.YES, Field.Index.NOT_ANALYZED));
    writer.addDocument(doc);

    reader = refreshReader(reader);
    searcher.close();
    searcher = newSearcher(reader, false);

    TopDocs docs = searcher.search(new MatchAllDocsQuery(), 1);
    assertEquals("Should find a hit...", 1, docs.totalHits);

    final SpanFilter startFilter = new SpanQueryFilter(new SpanTermQuery(new Term("id", "1")));

    // ignore deletions
    CachingSpanFilter filter = new CachingSpanFilter(startFilter, CachingWrapperFilter.DeletesMode.IGNORE);
        
    docs = searcher.search(new MatchAllDocsQuery(), filter, 1);
    assertEquals("[query + filter] Should find a hit...", 1, docs.totalHits);
    ConstantScoreQuery constantScore = new ConstantScoreQuery(filter);
    docs = searcher.search(constantScore, 1);
    assertEquals("[just filter] Should find a hit...", 1, docs.totalHits);

    // now delete the doc, refresh the reader, and see that
    // it's not there
    _TestUtil.keepFullyDeletedSegments(writer.w);
    writer.deleteDocuments(new Term("id", "1"));

    reader = refreshReader(reader);
    searcher.close();
    searcher = newSearcher(reader, false);

    docs = searcher.search(new MatchAllDocsQuery(), filter, 1);
    assertEquals("[query + filter] Should *not* find a hit...", 0, docs.totalHits);

    docs = searcher.search(constantScore, 1);
    assertEquals("[just filter] Should find a hit...", 1, docs.totalHits);


    // force cache to regenerate:
    filter = new CachingSpanFilter(startFilter, CachingWrapperFilter.DeletesMode.RECACHE);

    writer.addDocument(doc);
    reader = refreshReader(reader);
    searcher.close();
    searcher = newSearcher(reader, false);
        
    docs = searcher.search(new MatchAllDocsQuery(), filter, 1);
    assertEquals("[query + filter] Should find a hit...", 1, docs.totalHits);

    constantScore = new ConstantScoreQuery(filter);
    docs = searcher.search(constantScore, 1);
    assertEquals("[just filter] Should find a hit...", 1, docs.totalHits);

    // NOTE: important to hold ref here so GC doesn't clear
    // the cache entry!  Else the assert below may sometimes
    // fail:
    IndexReader oldReader = reader;

    // make sure we get a cache hit when we reopen readers
    // that had no new deletions
    reader = refreshReader(reader);
    assertTrue(reader != oldReader);
    searcher.close();
    searcher = newSearcher(reader, false);
    int missCount = filter.missCount;
    docs = searcher.search(constantScore, 1);
    assertEquals("[just filter] Should find a hit...", 1, docs.totalHits);
    assertEquals(missCount, filter.missCount);

    // now delete the doc, refresh the reader, and see that it's not there
    writer.deleteDocuments(new Term("id", "1"));

    reader = refreshReader(reader);
    searcher.close();
    searcher = newSearcher(reader, false);

    docs = searcher.search(new MatchAllDocsQuery(), filter, 1);
    assertEquals("[query + filter] Should *not* find a hit...", 0, docs.totalHits);

    docs = searcher.search(constantScore, 1);
    assertEquals("[just filter] Should *not* find a hit...", 0, docs.totalHits);

    // NOTE: silliness to make sure JRE does not optimize
    // away our holding onto oldReader to prevent
    // CachingWrapperFilter's WeakHashMap from dropping the
    // entry:
    assertTrue(oldReader != null);

    searcher.close();
    writer.close();
    reader.close();
    dir.close();
  }

  private static IndexReader refreshReader(IndexReader reader) throws IOException {
    IndexReader oldReader = reader;
    reader = reader.reopen();
    if (reader != oldReader) {
      oldReader.close();
    }
    return reader;
  }
}