io.druid.server.QueryManager.java Source code

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Here is the source code for io.druid.server.QueryManager.java

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/*
 * Druid - a distributed column store.
 * Copyright 2012 - 2015 Metamarkets Group Inc.
 *
 * Licensed 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 io.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 io.druid.query.Query;
import io.druid.query.QueryWatcher;

import java.util.Set;

public class QueryManager implements QueryWatcher {
    final SetMultimap<String, ListenableFuture> queries;

    public QueryManager() {
        this.queries = Multimaps.synchronizedSetMultimap(HashMultimap.<String, ListenableFuture>create());
    }

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

    public void registerQuery(Query query, final ListenableFuture future) {
        final String id = query.getId();
        queries.put(id, future);
        future.addListener(new Runnable() {
            @Override
            public void run() {
                queries.remove(id, future);
            }
        }, MoreExecutors.sameThreadExecutor());
    }
}