org.apache.lucene.facet.taxonomy.TaxonomyReader Java Examples

/** User drills down on 'Publish Date/2010', and we
 *  return facets for both 'Publish Date' and 'Author',
 *  using DrillSideways. */
private List<FacetResult> drillSideways() throws IOException {
  DirectoryReader indexReader = DirectoryReader.open(indexDir);
  IndexSearcher searcher = new IndexSearcher(indexReader);
  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

  // Passing no baseQuery means we drill down on all
  // documents ("browse only"):
  DrillDownQuery q = new DrillDownQuery(config);

  // Now user drills down on Publish Date/2010:
  q.add("Publish Date", "2010");

  DrillSideways ds = new DrillSideways(searcher, config, taxoReader);
  DrillSidewaysResult result = ds.search(q, 10);

  // Retrieve results
  List<FacetResult> facets = result.facets.getAllDims(10);

  indexReader.close();
  taxoReader.close();
  
  return facets;
}
 

/**
 * Add a new category into the index (and the cache), and return its new
 * ordinal.
 * <p>
 * Actually, we might also need to add some of the category's ancestors
 * before we can add the category itself (while keeping the invariant that a
 * parent is always added to the taxonomy before its child). We do this by
 * recursion.
 */
private int internalAddCategory(FacetLabel cp) throws IOException {
  // Find our parent's ordinal (recursively adding the parent category
  // to the taxonomy if it's not already there). Then add the parent
  // ordinal as payloads (rather than a stored field; payloads can be
  // more efficiently read into memory in bulk by LuceneTaxonomyReader)
  int parent;
  if (cp.length > 1) {
    FacetLabel parentPath = cp.subpath(cp.length - 1);
    parent = findCategory(parentPath);
    if (parent < 0) {
      parent = internalAddCategory(parentPath);
    }
  } else if (cp.length == 1) {
    parent = TaxonomyReader.ROOT_ORDINAL;
  } else {
    parent = TaxonomyReader.INVALID_ORDINAL;
  }
  int id = addCategoryDocument(cp, parent);

  return id;
}
 

private void computeChildrenSiblings(int first) {
  // reset the youngest child of all ordinals. while this should be done only
  // for the leaves, we don't know up front which are the leaves, so we reset
  // all of them.
  for (int i = first; i < parents.length; i++) {
    children[i] = TaxonomyReader.INVALID_ORDINAL;
  }
  
  // the root category has no parent, and therefore no siblings
  if (first == 0) {
    first = 1;
    siblings[0] = TaxonomyReader.INVALID_ORDINAL;
  }
  
  for (int i = first; i < parents.length; i++) {
    // note that parents[i] is always < i, so the right-hand-side of
    // the following line is already set when we get here
    siblings[i] = children[parents[i]];
    children[parents[i]] = i;
  }
}
 

@Test
public void testBackwardsCompatibility() throws Exception {
  // tests that if the taxonomy index doesn't have the INDEX_EPOCH
  // property (supports pre-3.6 indexes), all still works.
  Directory dir = newDirectory();
  
  // create an empty index first, so that DirTaxoWriter initializes indexEpoch to 1.
  new IndexWriter(dir, new IndexWriterConfig(null)).close();
  
  DirectoryTaxonomyWriter taxoWriter = new DirectoryTaxonomyWriter(dir, OpenMode.CREATE_OR_APPEND, NO_OP_CACHE);
  taxoWriter.close();
  
  DirectoryTaxonomyReader taxoReader = new DirectoryTaxonomyReader(dir);
  assertEquals(1, Integer.parseInt(taxoReader.getCommitUserData().get(DirectoryTaxonomyWriter.INDEX_EPOCH)));
  assertNull(TaxonomyReader.openIfChanged(taxoReader));
  taxoReader.close();
  
  dir.close();
}
 

protected DrillSideways getNewDrillSidewaysBuildFacetsResult(IndexSearcher searcher, FacetsConfig config,
        TaxonomyReader taxoReader) {
  return new DrillSideways(searcher, config, taxoReader, null, executor) {
    @Override
    protected Facets buildFacetsResult(FacetsCollector drillDowns, FacetsCollector[] drillSideways,
            String[] drillSidewaysDims) throws IOException {
      Map<String, Facets> drillSidewaysFacets = new HashMap<>();
      Facets drillDownFacets = getTaxonomyFacetCounts(taxoReader, config, drillDowns);
      if (drillSideways != null) {
        for (int i = 0; i < drillSideways.length; i++) {
          drillSidewaysFacets.put(drillSidewaysDims[i], getTaxonomyFacetCounts(taxoReader, config, drillSideways[i]));
        }
      }

      if (drillSidewaysFacets.isEmpty()) {
        return drillDownFacets;
      } else {
        return new MultiFacets(drillSidewaysFacets, drillDownFacets);
      }

    }
  };
}
 

@Test
public void testOpenIfChangedAndRefCount() throws Exception {
  Directory dir = new ByteBuffersDirectory(); // no need for random directories here

  DirectoryTaxonomyWriter taxoWriter = new DirectoryTaxonomyWriter(dir);
  taxoWriter.addCategory(new FacetLabel("a"));
  taxoWriter.commit();

  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(dir);
  assertEquals("wrong refCount", 1, taxoReader.getRefCount());

  taxoReader.incRef();
  assertEquals("wrong refCount", 2, taxoReader.getRefCount());

  taxoWriter.addCategory(new FacetLabel("a", "b"));
  taxoWriter.commit();
  TaxonomyReader newtr = TaxonomyReader.openIfChanged(taxoReader);
  assertNotNull(newtr);
  taxoReader.close();
  taxoReader = newtr;
  assertEquals("wrong refCount", 1, taxoReader.getRefCount());

  taxoWriter.close();
  taxoReader.close();
  dir.close();
}
 

protected DrillSideways getNewDrillSidewaysBuildFacetsResult(IndexSearcher searcher, FacetsConfig config,
        TaxonomyReader taxoReader) {
  return new DrillSideways(searcher, config, taxoReader) {
    @Override
    protected Facets buildFacetsResult(FacetsCollector drillDowns, FacetsCollector[] drillSideways,
            String[] drillSidewaysDims) throws IOException {
      Map<String, Facets> drillSidewaysFacets = new HashMap<>();
      Facets drillDownFacets = getTaxonomyFacetCounts(taxoReader, config, drillDowns);
      if (drillSideways != null) {
        for (int i = 0; i < drillSideways.length; i++) {
          drillSidewaysFacets.put(drillSidewaysDims[i], getTaxonomyFacetCounts(taxoReader, config, drillSideways[i]));
        }
      }

      if (drillSidewaysFacets.isEmpty()) {
        return drillDownFacets;
      } else {
        return new MultiFacets(drillSidewaysFacets, drillDownFacets);
      }

    }
  };
}
 

/** User drills down on 'tags/solr'. */
private FacetResult drillDown() throws IOException {
  DirectoryReader indexReader = DirectoryReader.open(indexDir);
  IndexSearcher searcher = new IndexSearcher(indexReader);
  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

  // Passing no baseQuery means we drill down on all
  // documents ("browse only"):
  DrillDownQuery q = new DrillDownQuery(config);

  // Now user drills down on Publish Date/2010:
  q.add("tags", "solr");
  FacetsCollector fc = new FacetsCollector();
  FacetsCollector.search(searcher, q, 10, fc);

  // Retrieve results
  Facets facets = new TaxonomyFacetSumFloatAssociations("$genre", taxoReader, config, fc);
  FacetResult result = facets.getTopChildren(10, "genre");

  indexReader.close();
  taxoReader.close();
  
  return result;
}
 

/** User runs a query and aggregates facets by summing their association values. */
private List<FacetResult> sumAssociations() throws IOException {
  DirectoryReader indexReader = DirectoryReader.open(indexDir);
  IndexSearcher searcher = new IndexSearcher(indexReader);
  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);
  
  FacetsCollector fc = new FacetsCollector();
  
  // MatchAllDocsQuery is for "browsing" (counts facets
  // for all non-deleted docs in the index); normally
  // you'd use a "normal" query:
  FacetsCollector.search(searcher, new MatchAllDocsQuery(), 10, fc);
  
  Facets tags = new TaxonomyFacetSumIntAssociations("$tags", taxoReader, config, fc);
  Facets genre = new TaxonomyFacetSumFloatAssociations("$genre", taxoReader, config, fc);

  // Retrieve results
  List<FacetResult> results = new ArrayList<>();
  results.add(tags.getTopChildren(10, "tags"));
  results.add(genre.getTopChildren(10, "genre"));

  indexReader.close();
  taxoReader.close();
  
  return results;
}
 

/** User drills down on 'Publish Date/2010', and we
 *  return facets for 'Author' */
private FacetResult drillDown() throws IOException {
  DirectoryReader indexReader = DirectoryReader.open(indexDir);
  IndexSearcher searcher = new IndexSearcher(indexReader);
  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

  // Passing no baseQuery means we drill down on all
  // documents ("browse only"):
  DrillDownQuery q = new DrillDownQuery(config);

  // Now user drills down on Publish Date/2010:
  q.add("Publish Date", "2010");
  FacetsCollector fc = new FacetsCollector();
  FacetsCollector.search(searcher, q, 10, fc);

  // Retrieve results
  Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
  FacetResult result = facets.getTopChildren(10, "Author");

  indexReader.close();
  taxoReader.close();
  
  return result;
}
 

public void testEmptyIndex() throws Exception {
  // LUCENE-5045: make sure DrillSideways works with an empty index
  Directory dir = newDirectory();
  Directory taxoDir = newDirectory();
  RandomIndexWriter writer = new RandomIndexWriter(random(), dir);
  DirectoryTaxonomyWriter taxoWriter = new DirectoryTaxonomyWriter(taxoDir, IndexWriterConfig.OpenMode.CREATE);
  IndexSearcher searcher = newSearcher(writer.getReader());
  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoWriter);

  // Count "Author"
  FacetsConfig config = new FacetsConfig();
  DrillSideways ds = getNewDrillSideways(searcher, config, taxoReader);
  DrillDownQuery ddq = new DrillDownQuery(config);
  ddq.add("Author", "Lisa");

  DrillSidewaysResult r = ds.search(ddq, 10); // this used to fail on IllegalArgEx
  assertEquals(0, r.hits.totalHits.value);

  r = ds.search(ddq, null, null, 10, new Sort(new SortField("foo", SortField.Type.INT)), false); // this used to fail on IllegalArgEx
  assertEquals(0, r.hits.totalHits.value);

  writer.close();
  IOUtils.close(taxoWriter, searcher.getIndexReader(), taxoReader, dir, taxoDir);
}
 

/** User runs a query and counts facets. */
private List<FacetResult> facetsWithSearch() throws IOException {
  DirectoryReader indexReader = DirectoryReader.open(indexDir);
  IndexSearcher searcher = new IndexSearcher(indexReader);
  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

  FacetsCollector fc = new FacetsCollector();

  // MatchAllDocsQuery is for "browsing" (counts facets
  // for all non-deleted docs in the index); normally
  // you'd use a "normal" query:
  FacetsCollector.search(searcher, new MatchAllDocsQuery(), 10, fc);

  // Retrieve results
  List<FacetResult> results = new ArrayList<>();

  // Count both "Publish Date" and "Author" dimensions
  Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
  results.add(facets.getTopChildren(10, "Author"));
  results.add(facets.getTopChildren(10, "Publish Date"));
  
  indexReader.close();
  taxoReader.close();
  
  return results;
}
 

/** User runs a query and counts facets. */
private List<FacetResult> facetsWithSearch() throws IOException {
    DirectoryReader indexReader = DirectoryReader.open(indexDir);
    IndexSearcher searcher = new IndexSearcher(indexReader);
    TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

    FacetsCollector fc = new FacetsCollector();

    // MatchAllDocsQuery is for "browsing" (counts facets
    // for all non-deleted docs in the index); normally
    // you'd use a "normal" query:
    FacetsCollector.search(searcher, new MatchAllDocsQuery(), 10, fc);

    // Retrieve results
    List<FacetResult> results = new ArrayList<FacetResult>();

    // Count both "Publish Date" and "Author" dimensions
    Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
    results.add(facets.getTopChildren(10, "Author"));
    results.add(facets.getTopChildren(10, "Publish Date"));

    indexReader.close();
    taxoReader.close();

    return results;
}
 

/** User drills down on 'Publish Date/2010', and we
 *  return facets for 'Author' */
private FacetResult drillDown() throws IOException {
    DirectoryReader indexReader = DirectoryReader.open(indexDir);
    IndexSearcher searcher = new IndexSearcher(indexReader);
    TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

    // Passing no baseQuery means we drill down on all
    // documents ("browse only"):
    DrillDownQuery q = new DrillDownQuery(config);

    // Now user drills down on Publish Date/2010:
    q.add("Publish Date", "2010");
    FacetsCollector fc = new FacetsCollector();
    FacetsCollector.search(searcher, q, 10, fc);

    // Retrieve results
    Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);
    FacetResult result = facets.getTopChildren(10, "Author");

    indexReader.close();
    taxoReader.close();

    return result;
}
 

/** User drills down on 'Publish Date/2010', and we
 *  return facets for both 'Publish Date' and 'Author',
 *  using DrillSideways. */
private List<FacetResult> drillSideways() throws IOException {
    DirectoryReader indexReader = DirectoryReader.open(indexDir);
    IndexSearcher searcher = new IndexSearcher(indexReader);
    TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

    // Passing no baseQuery means we drill down on all
    // documents ("browse only"):
    DrillDownQuery q = new DrillDownQuery(config);

    // Now user drills down on Publish Date/2010:
    q.add("Publish Date", "2010");

    DrillSideways ds = new DrillSideways(searcher, config, taxoReader);
    DrillSidewaysResult result = ds.search(q, 10);

    // Retrieve results

    List<FacetResult> facets = result.facets.getAllDims(10);

    indexReader.close();
    taxoReader.close();

    return facets;
}
 

private void openReaderIfChanges() throws IOException {
	DirectoryReader newDirectoryReader = DirectoryReader
			.openIfChanged(directoryReader, indexWriter, indexConfig.getIndexSettings().getApplyUncommittedDeletes());
	if (newDirectoryReader != null) {
		directoryReader = newDirectoryReader;
		QueryResultCache qrc = queryResultCache;
		if (qrc != null) {
			qrc.clear();
		}

	}

	DirectoryTaxonomyReader newone = TaxonomyReader.openIfChanged(taxoReader);
	if (newone != null) {
		taxoReader = newone;
	}
}
 

@Override
public int doLogic() throws IOException {
  try (TaxonomyReader taxoReader = getRunData().getTaxonomyReader()) {
    getRunData().setTaxonomyReader(null);
    if (taxoReader.getRefCount() != 1) {
      System.out.println("WARNING: CloseTaxonomyReader: reference count is currently " + taxoReader.getRefCount());
    }
  }
  return 1;
}
 

protected DrillSideways getNewDrillSidewaysScoreSubdocsAtOnce(IndexSearcher searcher, FacetsConfig config,
        TaxonomyReader taxoReader) {
  return new DrillSideways(searcher, config, taxoReader, null, executor) {
    @Override
    protected boolean scoreSubDocsAtOnce() {
      return true;
    }
  };
}
 

@Test
public void testDefault() throws Exception {
  Directory indexDir = newDirectory();
  Directory taxoDir = newDirectory();
  
  // create and open an index writer
  RandomIndexWriter iw = new RandomIndexWriter(random(), indexDir, newIndexWriterConfig(
      new MockAnalyzer(random(), MockTokenizer.WHITESPACE, false)));
  // create and open a taxonomy writer
  TaxonomyWriter tw = new DirectoryTaxonomyWriter(taxoDir, OpenMode.CREATE);
  FacetsConfig config = getConfig();

  seedIndex(tw, iw, config);

  IndexReader ir = iw.getReader();
  tw.commit();

  // prepare index reader and taxonomy.
  TaxonomyReader tr = new DirectoryTaxonomyReader(taxoDir);

  // prepare searcher to search against
  IndexSearcher searcher = newSearcher(ir);

  FacetsCollector sfc = performSearch(tr, ir, searcher);

  // Obtain facets results and hand-test them
  assertCorrectResults(getTaxonomyFacetCounts(tr, config, sfc));

  assertOrdinalsExist("$facets", ir);

  iw.close();
  IOUtils.close(tr, ir, tw, indexDir, taxoDir);
}
 

@Test
public void testCustom() throws Exception {
  Directory indexDir = newDirectory();
  Directory taxoDir = newDirectory();
  
  // create and open an index writer
  RandomIndexWriter iw = new RandomIndexWriter(random(), indexDir, newIndexWriterConfig(
      new MockAnalyzer(random(), MockTokenizer.WHITESPACE, false)));
  // create and open a taxonomy writer
  TaxonomyWriter tw = new DirectoryTaxonomyWriter(taxoDir, OpenMode.CREATE);

  FacetsConfig config = getConfig();
  config.setIndexFieldName("Author", "$author");
  seedIndex(tw, iw, config);

  IndexReader ir = iw.getReader();
  tw.commit();

  // prepare index reader and taxonomy.
  TaxonomyReader tr = new DirectoryTaxonomyReader(taxoDir);

  // prepare searcher to search against
  IndexSearcher searcher = newSearcher(ir);

  FacetsCollector sfc = performSearch(tr, ir, searcher);

  Map<String,Facets> facetsMap = new HashMap<>();
  facetsMap.put("Author", getTaxonomyFacetCounts(tr, config, sfc, "$author"));
  Facets facets = new MultiFacets(facetsMap, getTaxonomyFacetCounts(tr, config, sfc));

  // Obtain facets results and hand-test them
  assertCorrectResults(facets);

  assertOrdinalsExist("$facets", ir);
  assertOrdinalsExist("$author", ir);

  iw.close();
  IOUtils.close(tr, ir, tw, indexDir, taxoDir);
}
 

@Test
public void testRecreateAndRefresh() throws Exception {
  // DirTaxoWriter lost the INDEX_EPOCH property if it was opened in
  // CREATE_OR_APPEND (or commit(userData) called twice), which could lead to
  // DirTaxoReader succeeding to refresh().
  try (Directory dir = newDirectory()) {

    DirectoryTaxonomyWriter taxoWriter = new DirectoryTaxonomyWriter(dir, OpenMode.CREATE_OR_APPEND, NO_OP_CACHE);
    touchTaxo(taxoWriter, new FacetLabel("a"));

    TaxonomyReader taxoReader = new DirectoryTaxonomyReader(dir);

    touchTaxo(taxoWriter, new FacetLabel("b"));

    TaxonomyReader newtr = TaxonomyReader.openIfChanged(taxoReader);
    taxoReader.close();
    taxoReader = newtr;
    assertEquals(1, Integer.parseInt(taxoReader.getCommitUserData().get(DirectoryTaxonomyWriter.INDEX_EPOCH)));

    // now recreate the taxonomy, and check that the epoch is preserved after opening DirTW again.
    taxoWriter.close();

    taxoWriter = new DirectoryTaxonomyWriter(dir, OpenMode.CREATE, NO_OP_CACHE);
    touchTaxo(taxoWriter, new FacetLabel("c"));
    taxoWriter.close();

    taxoWriter = new DirectoryTaxonomyWriter(dir, OpenMode.CREATE_OR_APPEND, NO_OP_CACHE);
    touchTaxo(taxoWriter, new FacetLabel("d"));
    taxoWriter.close();

    newtr = TaxonomyReader.openIfChanged(taxoReader);
    taxoReader.close();
    taxoReader = newtr;
    assertEquals(2, Integer.parseInt(taxoReader.getCommitUserData().get(DirectoryTaxonomyWriter.INDEX_EPOCH)));
    taxoReader.close();
  }
}
 

@Test
public void testOpenIfChangedResult() throws Exception {
  Directory dir = null;
  DirectoryTaxonomyWriter ltw = null;
  DirectoryTaxonomyReader ltr = null;
  
  try {
    dir = newDirectory();
    ltw = new DirectoryTaxonomyWriter(dir);
    
    ltw.addCategory(new FacetLabel("a"));
    ltw.commit();
    
    ltr = new DirectoryTaxonomyReader(dir);
    assertNull("Nothing has changed", TaxonomyReader.openIfChanged(ltr));
    
    ltw.addCategory(new FacetLabel("b"));
    ltw.commit();
    
    DirectoryTaxonomyReader newtr = TaxonomyReader.openIfChanged(ltr);
    assertNotNull("changes were committed", newtr);
    assertNull("Nothing has changed", TaxonomyReader.openIfChanged(newtr));
    newtr.close();
  } finally {
    IOUtils.close(ltw, ltr, dir);
  }
}
 

@Test
public void testOpenIfChangedReuseAfterRecreate() throws Exception {
  // tests that if the taxonomy is recreated, no data is reused from the previous taxonomy
  Directory dir = newDirectory();
  DirectoryTaxonomyWriter writer = new DirectoryTaxonomyWriter(dir);
  FacetLabel cp_a = new FacetLabel("a");
  writer.addCategory(cp_a);
  writer.close();
  
  DirectoryTaxonomyReader r1 = new DirectoryTaxonomyReader(dir);
  // fill r1's caches
  assertEquals(1, r1.getOrdinal(cp_a));
  assertEquals(cp_a, r1.getPath(1));
  
  // now recreate, add a different category
  writer = new DirectoryTaxonomyWriter(dir, OpenMode.CREATE);
  FacetLabel cp_b = new FacetLabel("b");
  writer.addCategory(cp_b);
  writer.close();
  
  DirectoryTaxonomyReader r2 = TaxonomyReader.openIfChanged(r1);
  assertNotNull(r2);
  
  // fill r2's caches
  assertEquals(1, r2.getOrdinal(cp_b));
  assertEquals(cp_b, r2.getPath(1));
  
  // check that r1 doesn't see cp_b
  assertEquals(TaxonomyReader.INVALID_ORDINAL, r1.getOrdinal(cp_b));
  assertEquals(cp_a, r1.getPath(1));

  // check that r2 doesn't see cp_a
  assertEquals(TaxonomyReader.INVALID_ORDINAL, r2.getOrdinal(cp_a));
  assertEquals(cp_b, r2.getPath(1));

  r2.close();
  r1.close();
  dir.close();
}
 

@Test
public void testOpenIfChangedReuse() throws Exception {
  // test the reuse of data from the old DTR instance
  for (boolean nrt : new boolean[] {false, true}) {
    Directory dir = newDirectory();
    DirectoryTaxonomyWriter writer = new DirectoryTaxonomyWriter(dir);
    
    FacetLabel cp_a = new FacetLabel("a");
    writer.addCategory(cp_a);
    if (!nrt) writer.commit();
    
    DirectoryTaxonomyReader r1 = nrt ? new DirectoryTaxonomyReader(writer) : new DirectoryTaxonomyReader(dir);
    // fill r1's caches
    assertEquals(1, r1.getOrdinal(cp_a));
    assertEquals(cp_a, r1.getPath(1));
    
    FacetLabel cp_b = new FacetLabel("b");
    writer.addCategory(cp_b);
    if (!nrt) writer.commit();
    
    DirectoryTaxonomyReader r2 = TaxonomyReader.openIfChanged(r1);
    assertNotNull(r2);
    
    // add r2's categories to the caches
    assertEquals(2, r2.getOrdinal(cp_b));
    assertEquals(cp_b, r2.getPath(2));
    
    // check that r1 doesn't see cp_b
    assertEquals(TaxonomyReader.INVALID_ORDINAL, r1.getOrdinal(cp_b));
    assertNull(r1.getPath(2));
    
    r1.close();
    r2.close();
    writer.close();
    dir.close();
  }
}
 

/** User runs a query and counts facets only without collecting the matching documents.*/
private List<FacetResult> facetsOnly() throws IOException {
    DirectoryReader indexReader = DirectoryReader.open(indexDir);
    IndexSearcher searcher = new IndexSearcher(indexReader);
    TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

    FacetsCollector fc = new FacetsCollector();

    // MatchAllDocsQuery is for "browsing" (counts facets
    // for all non-deleted docs in the index); normally
    // you'd use a "normal" query:
    searcher.search(new MatchAllDocsQuery(), null /*Filter */, fc);

    // Retrieve results
    List<FacetResult> results = new ArrayList<FacetResult>();

    // Count both "Publish Date" and "Author" dimensions
    Facets facets = new FastTaxonomyFacetCounts(taxoReader, config, fc);

    results.add(facets.getTopChildren(10, "Author"));
    results.add(facets.getTopChildren(10, "Publish Date"));

    indexReader.close();
    taxoReader.close();

    return results;
}
 

public void testScorer() throws Exception {
  // LUCENE-6001 some scorers, eg ReqExlScorer, can hit NPE if cost is called after nextDoc
  Directory dir = newDirectory();
  Directory taxoDir = newDirectory();

  // Writes facet ords to a separate directory from the
  // main index:
  DirectoryTaxonomyWriter taxoWriter = new DirectoryTaxonomyWriter(taxoDir, IndexWriterConfig.OpenMode.CREATE);

  FacetsConfig config = new FacetsConfig();

  RandomIndexWriter writer = new RandomIndexWriter(random(), dir);

  Document doc = new Document();
  doc.add(newTextField("field", "foo bar", Field.Store.NO));
  doc.add(new FacetField("Author", "Bob"));
  doc.add(new FacetField("dim", "a"));
  writer.addDocument(config.build(taxoWriter, doc));

  // NRT open
  IndexSearcher searcher = newSearcher(writer.getReader());

  // NRT open
  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoWriter);

  DrillSideways ds = getNewDrillSideways(searcher, config, taxoReader);

  BooleanQuery.Builder bq = new BooleanQuery.Builder();
  bq.add(new TermQuery(new Term("field", "foo")), BooleanClause.Occur.MUST);
  bq.add(new TermQuery(new Term("field", "bar")), BooleanClause.Occur.MUST_NOT);
  DrillDownQuery ddq = new DrillDownQuery(config, bq.build());
  ddq.add("field", "foo");
  ddq.add("author", bq.build());
  ddq.add("dim", bq.build());
  DrillSidewaysResult r = ds.search(null, ddq, 10);
  assertEquals(0, r.hits.totalHits.value);

  writer.close();
  IOUtils.close(searcher.getIndexReader(), taxoReader, taxoWriter, dir, taxoDir);
}
 

/**
 * Set the taxonomy reader. Takes ownership of that taxonomy reader, that is,
 * internally performs taxoReader.incRef() (If caller no longer needs that 
 * reader it should decRef()/close() it after calling this method, otherwise, 
 * the reader will remain open). 
 * @param taxoReader The taxonomy reader to set.
 */
public synchronized void setTaxonomyReader(TaxonomyReader taxoReader) throws IOException {
  if (taxoReader == this.taxonomyReader) {
    return;
  }
  if (taxonomyReader != null) {
    taxonomyReader.decRef();
  }
  
  if (taxoReader != null) {
    taxoReader.incRef();
  }
  this.taxonomyReader = taxoReader;
}
 

/**
 * @return Returns the taxonomyReader.  NOTE: this returns a
 * reference.  You must call TaxonomyReader.decRef() when
 * you're done.
 */
public synchronized TaxonomyReader getTaxonomyReader() {
  if (taxonomyReader != null) {
    taxonomyReader.incRef();
  }
  return taxonomyReader;
}
 

/**
 * Test indexing with facets tasks.
 */
public void testIndexingWithFacets() throws Exception {
  // 1. alg definition (required in every "logic" test)
  String algLines[] = {
      "# ----- properties ",
      "content.source=org.apache.lucene.benchmark.byTask.feeds.LineDocSource",
      "docs.file=" + getReuters20LinesFile(),
      "content.source.log.step=100",
      "content.source.forever=false",
      "directory=ByteBuffersDirectory",
      "doc.stored=false",
      "merge.factor=3",
      "doc.tokenized=false",
      "debug.level=1",
      "# ----- alg ",
      "ResetSystemErase",
      "CreateIndex",
      "CreateTaxonomyIndex",
      "{ \"AddDocs\"  AddFacetedDoc > : * ",
      "CloseIndex",
      "CloseTaxonomyIndex",
      "OpenTaxonomyReader",
  };

  // 2. execute the algorithm  (required in every "logic" test)
  Benchmark benchmark = execBenchmark(algLines);
  PerfRunData runData = benchmark.getRunData();
  assertNull("taxo writer was not properly closed",runData.getTaxonomyWriter());
  TaxonomyReader taxoReader = runData.getTaxonomyReader();
  assertNotNull("taxo reader was not opened", taxoReader);
  assertTrue("nothing was added to the taxnomy (expecting root and at least one addtional category)",taxoReader.getSize()>1);
  taxoReader.close();
}
 

/** User runs a query and aggregates facets. */
private FacetResult search() throws IOException, ParseException {
  DirectoryReader indexReader = DirectoryReader.open(indexDir);
  IndexSearcher searcher = new IndexSearcher(indexReader);
  TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir);

  // Aggregate categories by an expression that combines the document's score
  // and its popularity field
  Expression expr = JavascriptCompiler.compile("_score * sqrt(popularity)");
  SimpleBindings bindings = new SimpleBindings();
  bindings.add("_score", DoubleValuesSource.SCORES); // the score of the document
  bindings.add("popularity", DoubleValuesSource.fromLongField("popularity")); // the value of the 'popularity' field

  // Aggregates the facet values
  FacetsCollector fc = new FacetsCollector(true);

  // MatchAllDocsQuery is for "browsing" (counts facets
  // for all non-deleted docs in the index); normally
  // you'd use a "normal" query:
  FacetsCollector.search(searcher, new MatchAllDocsQuery(), 10, fc);

  // Retrieve results
  Facets facets = new TaxonomyFacetSumValueSource(taxoReader, config, fc, expr.getDoubleValuesSource(bindings));
  FacetResult result = facets.getTopChildren(10, "A");
  
  indexReader.close();
  taxoReader.close();
  
  return result;
}