/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.lucene.demo.facet;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.lucene.analysis.core.WhitespaceAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.facet.DrillDownQuery;
import org.apache.lucene.facet.FacetResult;
import org.apache.lucene.facet.Facets;
import org.apache.lucene.facet.FacetsCollector;
import org.apache.lucene.facet.FacetsConfig;
import org.apache.lucene.facet.sortedset.DefaultSortedSetDocValuesReaderState;
import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetCounts;
import org.apache.lucene.facet.sortedset.SortedSetDocValuesFacetField;
import org.apache.lucene.facet.sortedset.SortedSetDocValuesReaderState;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.index.IndexWriterConfig.OpenMode;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.MatchAllDocsQuery;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
/** Shows simple usage of faceted indexing and search,
* using {@link SortedSetDocValuesFacetField} and {@link
* SortedSetDocValuesFacetCounts}. */
public class SimpleSortedSetFacetsExample {
private final Directory indexDir = new RAMDirectory();
private final FacetsConfig config = new FacetsConfig();
/** Empty constructor */
public SimpleSortedSetFacetsExample() {
}
/** Build the example index. */
private void index() throws IOException {
IndexWriter indexWriter = new IndexWriter(indexDir, new IndexWriterConfig(
new WhitespaceAnalyzer()).setOpenMode(OpenMode.CREATE));
Document doc = new Document();
doc.add(new SortedSetDocValuesFacetField("Author", "Bob"));
doc.add(new SortedSetDocValuesFacetField("Publish Year", "2010"));
indexWriter.addDocument(config.build(doc));
doc = new Document();
doc.add(new SortedSetDocValuesFacetField("Author", "Lisa"));
doc.add(new SortedSetDocValuesFacetField("Publish Year", "2010"));
indexWriter.addDocument(config.build(doc));
doc = new Document();
doc.add(new SortedSetDocValuesFacetField("Author", "Lisa"));
doc.add(new SortedSetDocValuesFacetField("Publish Year", "2012"));
indexWriter.addDocument(config.build(doc));
doc = new Document();
doc.add(new SortedSetDocValuesFacetField("Author", "Susan"));
doc.add(new SortedSetDocValuesFacetField("Publish Year", "2012"));
indexWriter.addDocument(config.build(doc));
doc = new Document();
doc.add(new SortedSetDocValuesFacetField("Author", "Frank"));
doc.add(new SortedSetDocValuesFacetField("Publish Year", "1999"));
indexWriter.addDocument(config.build(doc));
indexWriter.close();
}
/** User runs a query and counts facets. */
private List<FacetResult> search() throws IOException {
DirectoryReader indexReader = DirectoryReader.open(indexDir);
IndexSearcher searcher = new IndexSearcher(indexReader);
SortedSetDocValuesReaderState state = new DefaultSortedSetDocValuesReaderState(indexReader);
// Aggregatses the facet counts
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
Facets facets = new SortedSetDocValuesFacetCounts(state, fc);
List<FacetResult> results = new ArrayList<>();
results.add(facets.getTopChildren(10, "Author"));
results.add(facets.getTopChildren(10, "Publish Year"));
indexReader.close();
return results;
}
/** User drills down on 'Publish Year/2010'. */
private FacetResult drillDown() throws IOException {
DirectoryReader indexReader = DirectoryReader.open(indexDir);
IndexSearcher searcher = new IndexSearcher(indexReader);
SortedSetDocValuesReaderState state = new DefaultSortedSetDocValuesReaderState(indexReader);
// Now user drills down on Publish Year/2010:
DrillDownQuery q = new DrillDownQuery(config);
q.add("Publish Year", "2010");
FacetsCollector fc = new FacetsCollector();
FacetsCollector.search(searcher, q, 10, fc);
// Retrieve results
Facets facets = new SortedSetDocValuesFacetCounts(state, fc);
FacetResult result = facets.getTopChildren(10, "Author");
indexReader.close();
return result;
}
/** Runs the search example. */
public List<FacetResult> runSearch() throws IOException {
index();
return search();
}
/** Runs the drill-down example. */
public FacetResult runDrillDown() throws IOException {
index();
return drillDown();
}
/** Runs the search and drill-down examples and prints the results. */
public static void main(String[] args) throws Exception {
System.out.println("Facet counting example:");
System.out.println("-----------------------");
SimpleSortedSetFacetsExample example = new SimpleSortedSetFacetsExample();
List<FacetResult> results = example.runSearch();
System.out.println("Author: " + results.get(0));
System.out.println("Publish Year: " + results.get(0));
System.out.println("\n");
System.out.println("Facet drill-down example (Publish Year/2010):");
System.out.println("---------------------------------------------");
System.out.println("Author: " + example.runDrillDown());
}
}