org.apache.hive.service.server.ThreadWithGarbageCleanup.java Source code

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Here is the source code for org.apache.hive.service.server.ThreadWithGarbageCleanup.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.hive.service.server;

import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hive.metastore.HiveMetaStore;
import org.apache.hadoop.hive.metastore.RawStore;

/**
 * A HiveServer2 thread used to construct new server threads.
 * In particular, this thread ensures an orderly cleanup,
 * when killed by its corresponding ExecutorService.
 */
public class ThreadWithGarbageCleanup extends Thread {
    private static final Log LOG = LogFactory.getLog(ThreadWithGarbageCleanup.class);

    Map<Long, RawStore> threadRawStoreMap = ThreadFactoryWithGarbageCleanup.getThreadRawStoreMap();

    public ThreadWithGarbageCleanup(Runnable runnable) {
        super(runnable);
    }

    /**
     * Add any Thread specific garbage cleanup code here.
     * Currently, it shuts down the RawStore object for this thread if it is not null.
     */
    @Override
    public void finalize() throws Throwable {
        cleanRawStore();
        super.finalize();
    }

    private void cleanRawStore() {
        Long threadId = this.getId();
        RawStore threadLocalRawStore = threadRawStoreMap.get(threadId);
        if (threadLocalRawStore != null) {
            LOG.debug("RawStore: " + threadLocalRawStore + ", for the thread: " + this.getName()
                    + " will be closed now.");
            threadLocalRawStore.shutdown();
            threadRawStoreMap.remove(threadId);
        }
    }

    /**
     * Cache the ThreadLocal RawStore object. Called from the corresponding thread.
     */
    public void cacheThreadLocalRawStore() {
        Long threadId = this.getId();
        RawStore threadLocalRawStore = HiveMetaStore.HMSHandler.getRawStore();
        if (threadLocalRawStore != null && !threadRawStoreMap.containsKey(threadId)) {
            LOG.debug("Adding RawStore: " + threadLocalRawStore + ", for the thread: " + this.getName()
                    + " to threadRawStoreMap for future cleanup.");
            threadRawStoreMap.put(threadId, threadLocalRawStore);
        }
    }
}