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.spark.network.shuffle;
  
  import java.util.EventListener;
  
  import org.apache.spark.network.buffer.ManagedBuffer;
  
  public interface BlockFetchingListener extends EventListener {
    /**
     * Called once per successfully fetched block. After this call returns, data will be released
     * automatically. If the data will be passed to another thread, the receiver should retain()
     * and release() the buffer on their own, or copy the data to a new buffer.
     */
    void onBlockFetchSuccess(String blockId, ManagedBuffer data);
  
    /**
     * Called at least once per block upon failures.
     */
    void onBlockFetchFailure(String blockId, Throwable exception);
  }
  