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.journal;
  
  import alluxio.exception.status.AlluxioStatusException;
  import alluxio.grpc.GetQuorumInfoPResponse;
  import alluxio.grpc.GetTransferLeaderMessagePResponse;
  import alluxio.grpc.NetAddress;
  
  import java.io.Closeable;
  
  /**
   * Interface for a journal master client.
   */
  public interface JournalMasterClient extends Closeable {
    /**
     * Quorum information for participating servers in journal.
     *
     * @return list of server states in quorum
     */
    GetQuorumInfoPResponse getQuorumInfo() throws AlluxioStatusException;
  
    /**
     * Removes a server from journal quorum.
     *
     * @param serverAddress server address to remove from quorum
     * @throws AlluxioStatusException
     */
    void removeQuorumServer(NetAddress serverAddress) throws AlluxioStatusException;
  
    /**
     * Initiates changing the leading master of the quorum.
     *
     * @param newLeaderNetAddress server address of the prospective new leader
     * @throws AlluxioStatusException
     * @return the guid of transfer leader command
     */
    String transferLeadership(NetAddress newLeaderNetAddress) throws AlluxioStatusException;
  
    /**
     * Resets RaftPeer priorities.
     *
     * @throws AlluxioStatusException
     */
    void resetPriorities() throws AlluxioStatusException;
  
    /**
     * Gets exception messages thrown when transferring the leader.
     * @param transferId the guid of transferLeader command
     * @return exception message thrown when transferring the leader
     */
    GetTransferLeaderMessagePResponse getTransferLeaderMessage(String transferId)
            throws AlluxioStatusException;
  }
  