Example #1
0
  @Test
  public void testGetThatFieldProbabilityRatioIsReflectedInBoost() throws Exception {

    ArgumentCaptor<Float> normalizeCaptor = ArgumentCaptor.forClass(Float.class);

    DocumentFrequencyCorrection dfc = new DocumentFrequencyCorrection();

    Directory directory = newDirectory();

    Analyzer analyzer =
        new Analyzer() {
          protected TokenStreamComponents createComponents(String fieldName) {
            Tokenizer source = new WhitespaceTokenizer();
            TokenStream filter =
                new WordDelimiterFilter(
                    source,
                    WordDelimiterFilter.GENERATE_WORD_PARTS
                        | WordDelimiterFilter.SPLIT_ON_CASE_CHANGE,
                    null);
            filter = new LowerCaseFilter(filter);
            return new TokenStreamComponents(source, filter);
          }
        };

    IndexWriterConfig conf = new IndexWriterConfig(analyzer);
    conf.setCodec(Codec.forName(TestUtil.LUCENE_CODEC));
    IndexWriter indexWriter = new IndexWriter(directory, conf);

    // Both fields f1 and f2 have 10 terms in total.
    // f1: the search terms (abc def) make 100% of all terms in f1
    // f2: the search terms (abc def) make 50% of all terms in f2
    // --> we expect that the sum of the boost factors for terms in bq(+f1:abc, +f1:def)
    // equals 2 * sum of the boost factors for terms in bq(+f2:abc, +f2:def)

    PRMSFieldBoostTest.addNumDocs("f1", "abc def", indexWriter, 2);
    PRMSFieldBoostTest.addNumDocs("f1", "abc", indexWriter, 4);
    PRMSFieldBoostTest.addNumDocs("f1", "def", indexWriter, 2);
    PRMSFieldBoostTest.addNumDocs("f2", "abc def", indexWriter, 1);
    PRMSFieldBoostTest.addNumDocs("f2", "abc", indexWriter, 2);
    PRMSFieldBoostTest.addNumDocs("f2", "def", indexWriter, 1);
    PRMSFieldBoostTest.addNumDocs("f2", "ghi", indexWriter, 5);

    indexWriter.close();

    IndexReader indexReader = DirectoryReader.open(directory);
    IndexSearcher indexSearcher = new IndexSearcher(indexReader);
    indexSearcher.setSimilarity(similarity);

    Map<String, Float> fields = new HashMap<>();
    fields.put("f1", 1f);
    fields.put("f2", 1f);
    SearchFieldsAndBoosting searchFieldsAndBoosting =
        new SearchFieldsAndBoosting(FieldBoostModel.PRMS, fields, fields, 0.8f);

    LuceneQueryBuilder queryBuilder =
        new LuceneQueryBuilder(dfc, analyzer, searchFieldsAndBoosting, 0.01f, null);

    WhiteSpaceQuerqyParser parser = new WhiteSpaceQuerqyParser();

    Query query = queryBuilder.createQuery(parser.parse("AbcDef"));
    dfc.finishedUserQuery();

    assertTrue(query instanceof DisjunctionMaxQuery);

    DisjunctionMaxQuery dmq = (DisjunctionMaxQuery) query;
    List<Query> disjuncts = dmq.getDisjuncts();
    assertEquals(2, disjuncts.size());

    Query disjunct1 = disjuncts.get(0);
    if (disjunct1 instanceof BoostQuery) {
      disjunct1 = ((BoostQuery) disjunct1).getQuery();
    }
    assertTrue(disjunct1 instanceof BooleanQuery);

    BooleanQuery bq1 = (BooleanQuery) disjunct1;

    Query disjunct2 = disjuncts.get(1);
    if (disjunct2 instanceof BoostQuery) {
      disjunct2 = ((BoostQuery) disjunct2).getQuery();
    }
    assertTrue(disjunct2 instanceof BooleanQuery);

    BooleanQuery bq2 = (BooleanQuery) disjunct2;

    final Weight weight1 = bq1.createWeight(indexSearcher, true);
    weight1.normalize(0.1f, 4f);

    final Weight weight2 = bq2.createWeight(indexSearcher, true);
    weight2.normalize(0.1f, 4f);

    Mockito.verify(simWeight, times(4)).normalize(eq(0.1f), normalizeCaptor.capture());
    final List<Float> capturedBoosts = normalizeCaptor.getAllValues();

    // capturedBoosts = boosts of [bq1.term1, bq1.term2, bq2.term1, bq2.term2 ]
    assertEquals(capturedBoosts.get(0), capturedBoosts.get(1), 0.00001);
    assertEquals(capturedBoosts.get(2), capturedBoosts.get(3), 0.00001);
    assertEquals(2f, capturedBoosts.get(0) / capturedBoosts.get(3), 0.00001);

    indexReader.close();
    directory.close();
    analyzer.close();
  }