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.active;
  
  import org.apache.asterix.common.metadata.IDataset;
  import org.apache.hyracks.api.exceptions.HyracksDataException;
  
  public interface IActiveEntityEventsListener {
  
      /**
       * Notify the listener that an event related to the entity has taken place
       * Examples of such events include
       * 1. Job created
       * 2. Job completed
       * 3. Partition event
       *
       * @param event
       *            the event that took place
       */
      void notify(ActiveEvent event);
  
      /**
       * @return the state of the entity
       */
      ActivityState getState();
  
      /**
       * @return the active entity id
       */
      EntityId getEntityId();
  
      /**
       * dataset
       *
       * @return
       */
      boolean isEntityUsingDataset(IDataset dataset);
  
      /**
       * subscribe to events. subscription ends when subscriber.done() returns true
       *
       * @param subscriber
       */
      void subscribe(IActiveEntityEventSubscriber subscriber);
  
      /**
       * The most recent acquired stats for the active entity
       *
       * @return
       */
      String getStats();
  
      /**
       * @return The timestamp of the most recent acquired stats for the active entity
       */
      long getStatsTimeStamp();
  
      /**
       * refresh the stats
       *
       * @param timeout
       * @throws HyracksDataException throws ASX3118 if active entity is not currently running
       */
      void refreshStats(long timeout) throws HyracksDataException;
  
      /**
       * @return true, if entity is active, false otherwise
       */
      boolean isActive();
  
      /**
       * @return true, if this {@link IActiveEntityEventsListener} is suspended. Otherwise false.
       */
      boolean isSuspended();
  
      /**
       * unregister the listener upon deletion of entity
       *
       * @throws HyracksDataException
       */
      void unregister() throws HyracksDataException;
  
      /**
       * Get the job failure for the last failed run
       */
      Exception getJobFailure();
  
      /**
       * Get the stats name that's used to form the stats JSON for the active entity
       *
       * @return the customized stats name for current active entity
       */
      String getDisplayName() throws HyracksDataException;
  }
  