content: /*
   * 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.asterix.common.api;
  
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Set;
  
  import org.apache.asterix.common.api.IClusterManagementWork.ClusterState;
  
  public interface IClusterEventsSubscriber {
  
      /**
       * @param deadNodeIds
       * @return set of work to execute as a result of this node failure
       */
      default Set<IClusterManagementWork> notifyNodeFailure(Collection<String> deadNodeIds) {
          // default is no-op
          return Collections.emptySet();
      }
  
      /**
       * @param joinedNodeId
       * @return set of work to execute as a result of this node join
       */
      default Set<IClusterManagementWork> notifyNodeJoin(String joinedNodeId) {
          // default is no-op
          return Collections.emptySet();
      }
  
      /**
       * @param response
       */
      default void notifyRequestCompletion(IClusterManagementWorkResponse response) {
          // default is no-op
      }
  
      /**
       * @param previousState
       * @param newState
       */
      default void notifyStateChange(ClusterState newState) {
          // default is no-op
      }
  
  }
  