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.text.ParseException; 021import org.apache.lucene.analysis.core.WhitespaceAnalyzer; 022import org.apache.lucene.document.Document; 023import org.apache.lucene.document.Field.Store; 024import org.apache.lucene.document.NumericDocValuesField; 025import org.apache.lucene.document.TextField; 026import org.apache.lucene.expressions.Expression; 027import org.apache.lucene.expressions.SimpleBindings; 028import org.apache.lucene.expressions.js.JavascriptCompiler; 029import org.apache.lucene.facet.FacetField; 030import org.apache.lucene.facet.FacetResult; 031import org.apache.lucene.facet.Facets; 032import org.apache.lucene.facet.FacetsCollector; 033import org.apache.lucene.facet.FacetsConfig; 034import org.apache.lucene.facet.taxonomy.AssociationAggregationFunction; 035import org.apache.lucene.facet.taxonomy.TaxonomyFacetFloatAssociations; 036import org.apache.lucene.facet.taxonomy.TaxonomyReader; 037import org.apache.lucene.facet.taxonomy.directory.DirectoryTaxonomyReader; 038import org.apache.lucene.facet.taxonomy.directory.DirectoryTaxonomyWriter; 039import org.apache.lucene.index.DirectoryReader; 040import org.apache.lucene.index.IndexWriter; 041import org.apache.lucene.index.IndexWriterConfig; 042import org.apache.lucene.index.IndexWriterConfig.OpenMode; 043import org.apache.lucene.search.DoubleValuesSource; 044import org.apache.lucene.search.IndexSearcher; 045import org.apache.lucene.search.MatchAllDocsQuery; 046import org.apache.lucene.store.ByteBuffersDirectory; 047import org.apache.lucene.store.Directory; 048 049/** Shows facets aggregation by an expression. */ 050public class ExpressionAggregationFacetsExample { 051 052 private final Directory indexDir = new ByteBuffersDirectory(); 053 private final Directory taxoDir = new ByteBuffersDirectory(); 054 private final FacetsConfig config = new FacetsConfig(); 055 056 /** Empty constructor */ 057 public ExpressionAggregationFacetsExample() {} 058 059 /** Build the example index. */ 060 private void index() throws IOException { 061 IndexWriter indexWriter = 062 new IndexWriter( 063 indexDir, new IndexWriterConfig(new WhitespaceAnalyzer()).setOpenMode(OpenMode.CREATE)); 064 065 // Writes facet ords to a separate directory from the main index 066 DirectoryTaxonomyWriter taxoWriter = new DirectoryTaxonomyWriter(taxoDir); 067 068 Document doc = new Document(); 069 doc.add(new TextField("c", "foo bar", Store.NO)); 070 doc.add(new NumericDocValuesField("popularity", 5L)); 071 doc.add(new FacetField("A", "B")); 072 indexWriter.addDocument(config.build(taxoWriter, doc)); 073 074 doc = new Document(); 075 doc.add(new TextField("c", "foo foo bar", Store.NO)); 076 doc.add(new NumericDocValuesField("popularity", 3L)); 077 doc.add(new FacetField("A", "C")); 078 indexWriter.addDocument(config.build(taxoWriter, doc)); 079 080 indexWriter.close(); 081 taxoWriter.close(); 082 } 083 084 /** User runs a query and aggregates facets. */ 085 private FacetResult search() throws IOException, ParseException { 086 DirectoryReader indexReader = DirectoryReader.open(indexDir); 087 IndexSearcher searcher = new IndexSearcher(indexReader); 088 TaxonomyReader taxoReader = new DirectoryTaxonomyReader(taxoDir); 089 090 // Aggregate categories by an expression that combines the document's score 091 // and its popularity field 092 Expression expr = JavascriptCompiler.compile("_score * sqrt(popularity)"); 093 SimpleBindings bindings = new SimpleBindings(); 094 bindings.add("_score", DoubleValuesSource.SCORES); // the score of the document 095 bindings.add( 096 "popularity", 097 DoubleValuesSource.fromLongField("popularity")); // the value of the 'popularity' field 098 099 // Aggregates the facet values 100 FacetsCollector fc = new FacetsCollector(true); 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.search(searcher, new MatchAllDocsQuery(), 10, fc); 106 107 // Retrieve results 108 Facets facets = 109 new TaxonomyFacetFloatAssociations( 110 taxoReader, 111 config, 112 fc, 113 AssociationAggregationFunction.SUM, 114 expr.getDoubleValuesSource(bindings)); 115 FacetResult result = facets.getTopChildren(10, "A"); 116 117 indexReader.close(); 118 taxoReader.close(); 119 120 return result; 121 } 122 123 /** Runs the search example. */ 124 public FacetResult runSearch() throws IOException, ParseException { 125 index(); 126 return search(); 127 } 128 129 /** Runs the search and drill-down examples and prints the results. */ 130 public static void main(String[] args) throws Exception { 131 System.out.println("Facet counting example:"); 132 System.out.println("-----------------------"); 133 FacetResult result = new ExpressionAggregationFacetsExample().runSearch(); 134 System.out.println(result); 135 } 136}