| /* |
| * 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.solr.search; |
| |
| import java.io.IOException; |
| import java.util.Objects; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| import org.apache.lucene.index.LeafReaderContext; |
| import org.apache.lucene.search.Collector; |
| import org.apache.lucene.search.FilterLeafCollector; |
| import org.apache.lucene.search.LeafCollector; |
| import org.apache.lucene.search.ScoreMode; |
| |
| /** Allows a query to be cancelled */ |
| public class CancellableCollector implements Collector { |
| |
| /** Thrown when a query gets cancelled */ |
| public static class QueryCancelledException extends RuntimeException {} |
| |
| private final Collector collector; |
| private final AtomicBoolean isQueryCancelled; |
| |
| public CancellableCollector(Collector collector) { |
| Objects.requireNonNull( |
| collector, "Internal collector not provided but wrapper collector accessed"); |
| |
| this.collector = collector; |
| this.isQueryCancelled = new AtomicBoolean(); |
| } |
| |
| @Override |
| public LeafCollector getLeafCollector(LeafReaderContext context) throws IOException { |
| |
| if (isQueryCancelled.get()) { |
| throw new QueryCancelledException(); |
| } |
| |
| return new FilterLeafCollector(collector.getLeafCollector(context)) { |
| |
| @Override |
| public void collect(int doc) throws IOException { |
| if (isQueryCancelled.get()) { |
| throw new QueryCancelledException(); |
| } |
| in.collect(doc); |
| } |
| }; |
| } |
| |
| @Override |
| public ScoreMode scoreMode() { |
| return collector.scoreMode(); |
| } |
| |
| public void cancel() { |
| isQueryCancelled.compareAndSet(false, true); |
| } |
| |
| public Collector getInternalCollector() { |
| return collector; |
| } |
| } |