content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.client.job;
  
  import alluxio.conf.PropertyKey;
  import alluxio.resource.ResourcePool;
  import alluxio.worker.job.JobMasterClientContext;
  
  import java.io.IOException;
  import java.util.Queue;
  import java.util.concurrent.ConcurrentLinkedQueue;
  import javax.annotation.concurrent.ThreadSafe;
  
  /**
   * Class for managing job master clients. After obtaining a client with
   * {@link ResourcePool#acquire()}, {@link ResourcePool#release(Object)} must be called when the
   * thread is done using the client.
   */
  @ThreadSafe
  public final class JobMasterClientPool extends ResourcePool<JobMasterClient> {
    private final Queue<JobMasterClient> mClientList;
    private final JobMasterClientContext mMasterContext;
  
    /**
     * Creates a new job master client pool.
     *
     * @param context Job master connection information
     */
    public JobMasterClientPool(JobMasterClientContext context) {
      super(context.getClusterConf().getInt(PropertyKey.JOB_MASTER_CLIENT_THREADS));
      mClientList = new ConcurrentLinkedQueue<>();
      mMasterContext = context;
    }
  
    @Override
    public void close() throws IOException {
      JobMasterClient client;
      while ((client = mClientList.poll()) != null) {
        client.close();
      }
    }
  
    @Override
    public JobMasterClient createNewResource() {
      JobMasterClient client = JobMasterClient.Factory.create(mMasterContext);
      mClientList.add(client);
      return client;
    }
  }
  