001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.lucene.demo.facet; 018 019import java.io.IOException; 020import java.util.ArrayList; 021import java.util.List; 022import org.apache.lucene.analysis.core.WhitespaceAnalyzer; 023import org.apache.lucene.document.Document; 024import org.apache.lucene.document.Field; 025import org.apache.lucene.document.KeywordField; 026import org.apache.lucene.document.SortedDocValuesField; 027import org.apache.lucene.facet.FacetResult; 028import org.apache.lucene.facet.Facets; 029import org.apache.lucene.facet.FacetsCollector; 030import org.apache.lucene.facet.FacetsCollectorManager; 031import org.apache.lucene.facet.FacetsConfig; 032import org.apache.lucene.facet.StringDocValuesReaderState; 033import org.apache.lucene.facet.StringValueFacetCounts; 034import org.apache.lucene.index.DirectoryReader; 035import org.apache.lucene.index.IndexWriter; 036import org.apache.lucene.index.IndexWriterConfig; 037import org.apache.lucene.index.IndexWriterConfig.OpenMode; 038import org.apache.lucene.search.IndexSearcher; 039import org.apache.lucene.search.MatchAllDocsQuery; 040import org.apache.lucene.store.ByteBuffersDirectory; 041import org.apache.lucene.store.Directory; 042import org.apache.lucene.util.BytesRef; 043 044/** 045 * Demonstrate the use of {@link StringValueFacetCounts} over {@link SortedDocValuesField} and 046 * {@link KeywordField}. 047 */ 048public class StringValueFacetCountsExample { 049 050 private final Directory indexDir = new ByteBuffersDirectory(); 051 private final FacetsConfig config = new FacetsConfig(); 052 053 /** Empty constructor */ 054 public StringValueFacetCountsExample() {} 055 056 /** Build the example index. */ 057 private void index() throws IOException { 058 IndexWriter indexWriter = 059 new IndexWriter( 060 indexDir, new IndexWriterConfig(new WhitespaceAnalyzer()).setOpenMode(OpenMode.CREATE)); 061 062 Document doc = new Document(); 063 doc.add(new KeywordField("Author", "Bob", Field.Store.NO)); 064 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("2010"))); 065 indexWriter.addDocument(config.build(doc)); 066 067 doc = new Document(); 068 doc.add(new KeywordField("Author", "Lisa", Field.Store.NO)); 069 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("2010"))); 070 indexWriter.addDocument(config.build(doc)); 071 072 doc = new Document(); 073 doc.add(new KeywordField("Author", "Lisa", Field.Store.NO)); 074 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("2012"))); 075 indexWriter.addDocument(config.build(doc)); 076 077 doc = new Document(); 078 doc.add(new KeywordField("Author", "Susan", Field.Store.NO)); 079 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("2012"))); 080 indexWriter.addDocument(config.build(doc)); 081 082 doc = new Document(); 083 doc.add(new KeywordField("Author", "Frank", Field.Store.NO)); 084 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("1999"))); 085 indexWriter.addDocument(config.build(doc)); 086 087 indexWriter.close(); 088 } 089 090 /** User runs a query and counts facets. */ 091 private List<FacetResult> search() throws IOException { 092 DirectoryReader indexReader = DirectoryReader.open(indexDir); 093 IndexSearcher searcher = new IndexSearcher(indexReader); 094 095 StringDocValuesReaderState authorState = new StringDocValuesReaderState(indexReader, "Author"); 096 StringDocValuesReaderState publishState = 097 new StringDocValuesReaderState(indexReader, "Publish Year"); 098 099 // Aggregates the facet counts 100 FacetsCollectorManager fcm = new FacetsCollectorManager(); 101 102 // MatchAllDocsQuery is for "browsing" (counts facets 103 // for all non-deleted docs in the index); normally 104 // you'd use a "normal" query: 105 FacetsCollector fc = 106 FacetsCollectorManager.search(searcher, new MatchAllDocsQuery(), 10, fcm).facetsCollector(); 107 108 // Retrieve results 109 Facets authorFacets = new StringValueFacetCounts(authorState, fc); 110 Facets publishFacets = new StringValueFacetCounts(publishState, fc); 111 112 List<FacetResult> results = new ArrayList<>(); 113 results.add(authorFacets.getTopChildren(10, "Author")); 114 results.add(publishFacets.getTopChildren(10, "Publish Year")); 115 indexReader.close(); 116 117 return results; 118 } 119 120 /** Runs the search example. */ 121 public List<FacetResult> runSearch() throws IOException { 122 index(); 123 return search(); 124 } 125 126 /** Runs the search and drill-down examples and prints the results. */ 127 public static void main(String[] args) throws Exception { 128 System.out.println("Facet counting example:"); 129 System.out.println("-----------------------"); 130 StringValueFacetCountsExample example = new StringValueFacetCountsExample(); 131 List<FacetResult> results = example.runSearch(); 132 System.out.println("Author: " + results.get(0)); 133 System.out.println("Publish Year: " + results.get(1)); 134 } 135}