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.FacetsConfig; 031import org.apache.lucene.facet.StringDocValuesReaderState; 032import org.apache.lucene.facet.StringValueFacetCounts; 033import org.apache.lucene.index.DirectoryReader; 034import org.apache.lucene.index.IndexWriter; 035import org.apache.lucene.index.IndexWriterConfig; 036import org.apache.lucene.index.IndexWriterConfig.OpenMode; 037import org.apache.lucene.search.IndexSearcher; 038import org.apache.lucene.search.MatchAllDocsQuery; 039import org.apache.lucene.store.ByteBuffersDirectory; 040import org.apache.lucene.store.Directory; 041import org.apache.lucene.util.BytesRef; 042 043/** 044 * Demonstrate the use of {@link StringValueFacetCounts} over {@link SortedDocValuesField} and 045 * {@link KeywordField}. 046 */ 047public class StringValueFacetCountsExample { 048 049 private final Directory indexDir = new ByteBuffersDirectory(); 050 private final FacetsConfig config = new FacetsConfig(); 051 052 /** Empty constructor */ 053 public StringValueFacetCountsExample() {} 054 055 /** Build the example index. */ 056 private void index() throws IOException { 057 IndexWriter indexWriter = 058 new IndexWriter( 059 indexDir, new IndexWriterConfig(new WhitespaceAnalyzer()).setOpenMode(OpenMode.CREATE)); 060 061 Document doc = new Document(); 062 doc.add(new KeywordField("Author", "Bob", Field.Store.NO)); 063 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("2010"))); 064 indexWriter.addDocument(config.build(doc)); 065 066 doc = new Document(); 067 doc.add(new KeywordField("Author", "Lisa", Field.Store.NO)); 068 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("2010"))); 069 indexWriter.addDocument(config.build(doc)); 070 071 doc = new Document(); 072 doc.add(new KeywordField("Author", "Lisa", Field.Store.NO)); 073 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("2012"))); 074 indexWriter.addDocument(config.build(doc)); 075 076 doc = new Document(); 077 doc.add(new KeywordField("Author", "Susan", Field.Store.NO)); 078 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("2012"))); 079 indexWriter.addDocument(config.build(doc)); 080 081 doc = new Document(); 082 doc.add(new KeywordField("Author", "Frank", Field.Store.NO)); 083 doc.add(new SortedDocValuesField("Publish Year", new BytesRef("1999"))); 084 indexWriter.addDocument(config.build(doc)); 085 086 indexWriter.close(); 087 } 088 089 /** User runs a query and counts facets. */ 090 private List<FacetResult> search() throws IOException { 091 DirectoryReader indexReader = DirectoryReader.open(indexDir); 092 IndexSearcher searcher = new IndexSearcher(indexReader); 093 094 StringDocValuesReaderState authorState = new StringDocValuesReaderState(indexReader, "Author"); 095 StringDocValuesReaderState publishState = 096 new StringDocValuesReaderState(indexReader, "Publish Year"); 097 098 // Aggregatses the facet counts 099 FacetsCollector fc = new FacetsCollector(); 100 101 // MatchAllDocsQuery is for "browsing" (counts facets 102 // for all non-deleted docs in the index); normally 103 // you'd use a "normal" query: 104 FacetsCollector.search(searcher, new MatchAllDocsQuery(), 10, fc); 105 106 // Retrieve results 107 Facets authorFacets = new StringValueFacetCounts(authorState, fc); 108 Facets publishFacets = new StringValueFacetCounts(publishState, fc); 109 110 List<FacetResult> results = new ArrayList<>(); 111 results.add(authorFacets.getTopChildren(10, "Author")); 112 results.add(publishFacets.getTopChildren(10, "Publish Year")); 113 indexReader.close(); 114 115 return results; 116 } 117 118 /** Runs the search example. */ 119 public List<FacetResult> runSearch() throws IOException { 120 index(); 121 return search(); 122 } 123 124 /** Runs the search and drill-down examples and prints the results. */ 125 public static void main(String[] args) throws Exception { 126 System.out.println("Facet counting example:"); 127 System.out.println("-----------------------"); 128 StringValueFacetCountsExample example = new StringValueFacetCountsExample(); 129 List<FacetResult> results = example.runSearch(); 130 System.out.println("Author: " + results.get(0)); 131 System.out.println("Publish Year: " + results.get(1)); 132 } 133}