package org.apache.lucene.facet.example.adaptive;
import java.util.List;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TopScoreDocCollector;
import org.apache.lucene.store.Directory;
import org.apache.lucene.search.MultiCollector;
import org.apache.lucene.facet.example.ExampleUtils;
import org.apache.lucene.facet.example.simple.SimpleUtils;
import org.apache.lucene.facet.search.AdaptiveFacetsAccumulator;
import org.apache.lucene.facet.search.ScoredDocIdCollector;
import org.apache.lucene.facet.search.params.CountFacetRequest;
import org.apache.lucene.facet.search.params.FacetSearchParams;
import org.apache.lucene.facet.search.results.FacetResult;
import org.apache.lucene.facet.taxonomy.CategoryPath;
import org.apache.lucene.facet.taxonomy.TaxonomyReader;
import org.apache.lucene.facet.taxonomy.directory.DirectoryTaxonomyReader;
/*
* 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.
*/
/**
* Search with facets through the {@link AdaptiveFacetsAccumulator}
*
* @lucene.experimental
*/
public class AdaptiveSearcher {
/**
* Search with facets through the {@link AdaptiveFacetsAccumulator}
* @param indexDir Directory of the search index.
* @param taxoDir Directory of the taxonomy index.
* @throws Exception on error (no detailed exception handling here for sample simplicity
* @return facet results
*/
public static List<FacetResult> searchWithFacets (Directory indexDir, Directory taxoDir) throws Exception {
// prepare index reader and taxonomy.
TaxonomyReader taxo = new DirectoryTaxonomyReader(taxoDir);
IndexReader indexReader = DirectoryReader.open(indexDir);
// prepare searcher to search against
IndexSearcher searcher = new IndexSearcher(indexReader);
// faceted search is working in 2 steps:
// 1. collect matching documents
// 2. aggregate facets for collected documents and
// generate the requested faceted results from the aggregated facets
// step 1: collect matching documents into a collector
Query q = new TermQuery(new Term(SimpleUtils.TEXT,"white"));
ExampleUtils.log("Query: "+q);
// regular collector for scoring matched documents
TopScoreDocCollector topDocsCollector = TopScoreDocCollector.create(10, true);
// docids collector for guiding facets accumulation (scoring disabled)
ScoredDocIdCollector docIdsCollecor = ScoredDocIdCollector.create(indexReader.maxDoc(), false);
// Faceted search parameters indicate which facets are we interested in
FacetSearchParams facetSearchParams = new FacetSearchParams();
facetSearchParams.addFacetRequest(new CountFacetRequest(new CategoryPath("root","a"), 10));
// search, into both collectors. note: in case only facets accumulation
// is required, the topDocCollector part can be totally discarded
searcher.search(q, MultiCollector.wrap(topDocsCollector, docIdsCollecor));
// Obtain facets results and print them
AdaptiveFacetsAccumulator accumulator = new AdaptiveFacetsAccumulator(facetSearchParams, indexReader, taxo);
List<FacetResult> res = accumulator.accumulate(docIdsCollecor.getScoredDocIDs());
int i = 0;
for (FacetResult facetResult : res) {
ExampleUtils.log("Res "+(i++)+": "+facetResult);
}
// we're done, close the index reader and the taxonomy.
indexReader.close();
taxo.close();
return res;
}
}