org.apache.druid.server.QueryManager.java Source code

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Here is the source code for org.apache.druid.server.QueryManager.java

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/*
 * 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.druid.server;

import com.google.common.collect.HashMultimap;
import com.google.common.collect.Multimaps;
import com.google.common.collect.SetMultimap;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.MoreExecutors;
import org.apache.druid.query.Query;
import org.apache.druid.query.QueryWatcher;

import java.util.List;
import java.util.Set;

public class QueryManager implements QueryWatcher {

    private final SetMultimap<String, ListenableFuture> queries;
    private final SetMultimap<String, String> queryDatasources;

    public QueryManager() {
        this.queries = Multimaps.synchronizedSetMultimap(HashMultimap.create());
        this.queryDatasources = Multimaps.synchronizedSetMultimap(HashMultimap.create());
    }

    public boolean cancelQuery(String id) {
        queryDatasources.removeAll(id);
        Set<ListenableFuture> futures = queries.removeAll(id);
        boolean success = true;
        for (ListenableFuture future : futures) {
            success = success && future.cancel(true);
        }
        return success;
    }

    @Override
    public void registerQuery(Query query, final ListenableFuture future) {
        final String id = query.getId();
        final List<String> datasources = query.getDataSource().getNames();
        queries.put(id, future);
        queryDatasources.putAll(id, datasources);
        future.addListener(new Runnable() {
            @Override
            public void run() {
                queries.remove(id, future);
                for (String datasource : datasources) {
                    queryDatasources.remove(id, datasource);
                }
            }
        }, MoreExecutors.sameThreadExecutor());
    }

    public Set<String> getQueryDatasources(final String queryId) {
        return queryDatasources.get(queryId);
    }
}