001package org.apache.lucene.demo.facet;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one or more
005 * contributor license agreements.  See the NOTICE file distributed with
006 * this work for additional information regarding copyright ownership.
007 * The ASF licenses this file to You under the Apache License, Version 2.0
008 * (the "License"); you may not use this file except in compliance with
009 * the License.  You may obtain a copy of the License at
010 *
011 *     http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 */
019
020import java.io.IOException;
021import java.util.ArrayList;
022import java.util.List;
023
024import org.apache.lucene.analysis.core.WhitespaceAnalyzer;
025import org.apache.lucene.document.Document;
026import org.apache.lucene.facet.DrillDownQuery;
027import org.apache.lucene.facet.FacetResult;
028import org.apache.lucene.facet.Facets;
029import org.apache.lucene.facet.FacetsCollector;
030import org.apache.lucene.facet.FacetsConfig;
031import org.apache.lucene.facet.sortedset.DefaultSortedSetDocValuesReaderState;
032import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetCounts;
033import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetField;
034import org.apache.lucene.facet.sortedset.SortedSetDocValuesReaderState;
035import org.apache.lucene.index.DirectoryReader;
036import org.apache.lucene.index.IndexWriter;
037import org.apache.lucene.index.IndexWriterConfig;
038import org.apache.lucene.search.IndexSearcher;
039import org.apache.lucene.search.MatchAllDocsQuery;
040import org.apache.lucene.store.Directory;
041import org.apache.lucene.store.RAMDirectory;
042
043/** Shows simple usage of faceted indexing and search,
044 *  using {@link SortedSetDocValuesFacetField} and {@link
045 *  SortedSetDocValuesFacetCounts}.  */
046
047public class SimpleSortedSetFacetsExample {
048
049  private final Directory indexDir = new RAMDirectory();
050  private final FacetsConfig config = new FacetsConfig();
051
052  /** Empty constructor */
053  public SimpleSortedSetFacetsExample() {
054  }
055
056  /** Build the example index. */
057  private void index() throws IOException {
058    IndexWriter indexWriter = new IndexWriter(indexDir, new IndexWriterConfig(FacetExamples.EXAMPLES_VER, 
059        new WhitespaceAnalyzer(FacetExamples.EXAMPLES_VER)));
060    Document doc = new Document();
061    doc.add(new SortedSetDocValuesFacetField("Author", "Bob"));
062    doc.add(new SortedSetDocValuesFacetField("Publish Year", "2010"));
063    indexWriter.addDocument(config.build(doc));
064
065    doc = new Document();
066    doc.add(new SortedSetDocValuesFacetField("Author", "Lisa"));
067    doc.add(new SortedSetDocValuesFacetField("Publish Year", "2010"));
068    indexWriter.addDocument(config.build(doc));
069
070    doc = new Document();
071    doc.add(new SortedSetDocValuesFacetField("Author", "Lisa"));
072    doc.add(new SortedSetDocValuesFacetField("Publish Year", "2012"));
073    indexWriter.addDocument(config.build(doc));
074
075    doc = new Document();
076    doc.add(new SortedSetDocValuesFacetField("Author", "Susan"));
077    doc.add(new SortedSetDocValuesFacetField("Publish Year", "2012"));
078    indexWriter.addDocument(config.build(doc));
079
080    doc = new Document();
081    doc.add(new SortedSetDocValuesFacetField("Author", "Frank"));
082    doc.add(new SortedSetDocValuesFacetField("Publish Year", "1999"));
083    indexWriter.addDocument(config.build(doc));
084    
085    indexWriter.close();
086  }
087
088  /** User runs a query and counts facets. */
089  private List<FacetResult> search() throws IOException {
090    DirectoryReader indexReader = DirectoryReader.open(indexDir);
091    IndexSearcher searcher = new IndexSearcher(indexReader);
092    SortedSetDocValuesReaderState state = new DefaultSortedSetDocValuesReaderState(indexReader);
093
094    // Aggregatses the facet counts
095    FacetsCollector fc = new FacetsCollector();
096
097    // MatchAllDocsQuery is for "browsing" (counts facets
098    // for all non-deleted docs in the index); normally
099    // you'd use a "normal" query:
100    FacetsCollector.search(searcher, new MatchAllDocsQuery(), 10, fc);
101
102    // Retrieve results
103    Facets facets = new SortedSetDocValuesFacetCounts(state, fc);
104
105    List<FacetResult> results = new ArrayList<>();
106    results.add(facets.getTopChildren(10, "Author"));
107    results.add(facets.getTopChildren(10, "Publish Year"));
108    indexReader.close();
109    
110    return results;
111  }
112  
113  /** User drills down on 'Publish Year/2010'. */
114  private FacetResult drillDown() throws IOException {
115    DirectoryReader indexReader = DirectoryReader.open(indexDir);
116    IndexSearcher searcher = new IndexSearcher(indexReader);
117    SortedSetDocValuesReaderState state = new DefaultSortedSetDocValuesReaderState(indexReader);
118
119    // Now user drills down on Publish Year/2010:
120    DrillDownQuery q = new DrillDownQuery(config);
121    q.add("Publish Year", "2010");
122    FacetsCollector fc = new FacetsCollector();
123    FacetsCollector.search(searcher, q, 10, fc);
124
125    // Retrieve results
126    Facets facets = new SortedSetDocValuesFacetCounts(state, fc);
127    FacetResult result = facets.getTopChildren(10, "Author");
128    indexReader.close();
129    
130    return result;
131  }
132
133  /** Runs the search example. */
134  public List<FacetResult> runSearch() throws IOException {
135    index();
136    return search();
137  }
138  
139  /** Runs the drill-down example. */
140  public FacetResult runDrillDown() throws IOException {
141    index();
142    return drillDown();
143  }
144
145  /** Runs the search and drill-down examples and prints the results. */
146  public static void main(String[] args) throws Exception {
147    System.out.println("Facet counting example:");
148    System.out.println("-----------------------");
149    SimpleSortedSetFacetsExample example = new SimpleSortedSetFacetsExample();
150    List<FacetResult> results = example.runSearch();
151    System.out.println("Author: " + results.get(0));
152    System.out.println("Publish Year: " + results.get(0));
153
154    System.out.println("\n");
155    System.out.println("Facet drill-down example (Publish Year/2010):");
156    System.out.println("---------------------------------------------");
157    System.out.println("Author: " + example.runDrillDown());
158  }
159}