| /* |
| * 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.search.join; |
| |
| import java.io.IOException; |
| import java.util.Collections; |
| import java.util.Map; |
| import java.util.WeakHashMap; |
| |
| import org.apache.lucene.index.IndexReader; |
| import org.apache.lucene.index.IndexReaderContext; |
| import org.apache.lucene.index.LeafReader; |
| import org.apache.lucene.index.LeafReaderContext; |
| import org.apache.lucene.index.ReaderUtil; |
| import org.apache.lucene.search.DocIdSet; |
| import org.apache.lucene.search.IndexSearcher; |
| import org.apache.lucene.search.Query; |
| import org.apache.lucene.search.Scorer; |
| import org.apache.lucene.search.Weight; |
| import org.apache.lucene.util.BitDocIdSet; |
| import org.apache.lucene.util.BitSet; |
| |
| /** |
| * A {@link BitSetProducer} that wraps a query and caches matching |
| * {@link BitSet}s per segment. |
| */ |
| public class QueryBitSetProducer implements BitSetProducer { |
| private final Query query; |
| final Map<IndexReader.CacheKey,DocIdSet> cache = Collections.synchronizedMap(new WeakHashMap<>()); |
| |
| /** Wraps another query's result and caches it into bitsets. |
| * @param query Query to cache results of |
| */ |
| public QueryBitSetProducer(Query query) { |
| this.query = query; |
| } |
| |
| /** |
| * Gets the contained query. |
| * @return the contained query. |
| */ |
| public Query getQuery() { |
| return query; |
| } |
| |
| @Override |
| public BitSet getBitSet(LeafReaderContext context) throws IOException { |
| final LeafReader reader = context.reader(); |
| final IndexReader.CacheHelper cacheHelper = reader.getCoreCacheHelper(); |
| |
| DocIdSet docIdSet = null; |
| if (cacheHelper != null) { |
| docIdSet = cache.get(cacheHelper.getKey()); |
| } |
| if (docIdSet == null) { |
| final IndexReaderContext topLevelContext = ReaderUtil.getTopLevelContext(context); |
| final IndexSearcher searcher = new IndexSearcher(topLevelContext); |
| searcher.setQueryCache(null); |
| final Query rewritten = searcher.rewrite(query); |
| final Weight weight = searcher.createWeight(rewritten, org.apache.lucene.search.ScoreMode.COMPLETE_NO_SCORES, 1); |
| final Scorer s = weight.scorer(context); |
| |
| if (s == null) { |
| docIdSet = DocIdSet.EMPTY; |
| } else { |
| docIdSet = new BitDocIdSet(BitSet.of(s.iterator(), context.reader().maxDoc())); |
| } |
| if (cacheHelper != null) { |
| cache.put(cacheHelper.getKey(), docIdSet); |
| } |
| } |
| return docIdSet == DocIdSet.EMPTY ? null : ((BitDocIdSet) docIdSet).bits(); |
| } |
| |
| @Override |
| public String toString() { |
| return getClass().getSimpleName() + "("+query.toString()+")"; |
| } |
| |
| @Override |
| public boolean equals(Object o) { |
| if (o == null || getClass() != o.getClass()) { |
| return false; |
| } |
| final QueryBitSetProducer other = (QueryBitSetProducer) o; |
| return this.query.equals(other.query); |
| } |
| |
| @Override |
| public int hashCode() { |
| return 31 * getClass().hashCode() + query.hashCode(); |
| } |
| } |