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;
  
  import alluxio.exception.status.UnavailableException;
  import alluxio.grpc.GrpcServerAddress;
  import alluxio.master.MasterClientContext;
  import alluxio.master.MasterInquireClient;
  import alluxio.master.selectionpolicy.MasterSelectionPolicy;
  import alluxio.retry.RetryPolicy;
  
  import java.io.IOException;
  import java.net.InetSocketAddress;
  import java.util.function.Supplier;
  import javax.annotation.concurrent.ThreadSafe;
  
  /**
   * The base class for master clients.
   */
  @ThreadSafe
  public abstract class AbstractMasterClient extends AbstractClient {
    /** Client for determining the master RPC address. */
    private final MasterInquireClient mMasterInquireClient;
  
    private final MasterSelectionPolicy mMasterSelectionPolicy;
  
    /**
     * Creates a new master client base and default the selection policy to primary master.
     *
     * @param clientConf master client configuration
     */
    public AbstractMasterClient(MasterClientContext clientConf) {
      this(clientConf, MasterSelectionPolicy.Factory.primaryMaster());
    }
  
    /**
     * Creates a new master client base.
     *
     * @param clientConf master client configuration
     * @param selectionPolicy master selection policy: which master the client should connect to
     */
    public AbstractMasterClient(
        MasterClientContext clientConf, MasterSelectionPolicy selectionPolicy) {
      super(clientConf);
      mMasterInquireClient = clientConf.getMasterInquireClient();
      mMasterSelectionPolicy = selectionPolicy;
    }
  
    /**
     * Creates a new master client without a specific address.
     * The client defaults to connect to the primary master.
     * @param clientConf master client configuration
     * @param retryPolicySupplier retry policy to use
     */
    public AbstractMasterClient(
        MasterClientContext clientConf, Supplier<RetryPolicy> retryPolicySupplier) {
      super(clientConf, retryPolicySupplier);
      mMasterInquireClient = clientConf.getMasterInquireClient();
      mMasterSelectionPolicy = MasterSelectionPolicy.Factory.primaryMaster();
    }
  
    /**
     * Creates a new master client without a specific address.
     * @param clientConf master client configuration
     * @param selectionPolicy master selection policy: which master the client should connect to
     * @param retryPolicySupplier retry policy to use
     */
    public AbstractMasterClient(
        MasterClientContext clientConf,
        MasterSelectionPolicy selectionPolicy,
        Supplier<RetryPolicy> retryPolicySupplier) {
      super(clientConf, retryPolicySupplier);
      mMasterInquireClient = clientConf.getMasterInquireClient();
      mMasterSelectionPolicy = selectionPolicy;
    }
  
    @Override
    public synchronized InetSocketAddress getConfAddress() throws UnavailableException {
      return mMasterSelectionPolicy.getPrimaryMasterAddressCached(mMasterInquireClient);
    }
  
    @Override
    protected void beforeConnect() throws IOException {
      mMasterSelectionPolicy.resetPrimaryMasterAddressCache();
      super.beforeConnect();
    }
  
    @Override
    protected void afterDisconnect() {
      super.afterDisconnect();
      mMasterSelectionPolicy.resetPrimaryMasterAddressCache();
    }
  
    @Override
    protected synchronized GrpcServerAddress queryGrpcServerAddress() throws UnavailableException {
      return GrpcServerAddress.create(
          mMasterSelectionPolicy.getGrpcMasterAddress(mMasterInquireClient));
    }
  }
  