/*

  * 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.giraph.master;

 import org.apache.giraph.master.input.MasterInputSplitsHandler;

 import org.apache.giraph.partition.PartitionStats;

 import org.apache.giraph.reducers.ReduceOperation;

 import org.apache.giraph.utils.BlockingElementsSet;

 import org.apache.hadoop.io.Writable;

 import org.apache.hadoop.util.Progressable;

 import com.google.common.collect.Iterables;

 import java.util.List;

 /**

  * Handler for all master communications

  */

 public class MasterGlobalCommHandler implements MasterGlobalCommUsage {

   /** Aggregator handler */

   private final MasterAggregatorHandler aggregatorHandler;

   /** Input splits handler*/

   private final MasterInputSplitsHandler inputSplitsHandler;

   /** Partition stats received from workers */

   private final BlockingElementsSet<List<PartitionStats>> partitionStats =

       new BlockingElementsSet<>();

   /**

    * Constructor

    *

    * @param aggregatorHandler Aggregator handler

    * @param inputSplitsHandler Input splits handler

    */

   public MasterGlobalCommHandler(

       MasterAggregatorHandler aggregatorHandler,

       MasterInputSplitsHandler inputSplitsHandler) {

     this.aggregatorHandler = aggregatorHandler;

     this.inputSplitsHandler = inputSplitsHandler;

   }

   public MasterAggregatorHandler getAggregatorHandler() {

     return aggregatorHandler;

   }

   public MasterInputSplitsHandler getInputSplitsHandler() {

     return inputSplitsHandler;

   }

   @Override

   public <S, R extends Writable> void registerReducer(String name,

       ReduceOperation<S, R> reduceOp) {

     aggregatorHandler.registerReducer(name, reduceOp);

   }

   @Override

   public <S, R extends Writable> void registerReducer(String name,

       ReduceOperation<S, R> reduceOp, R globalInitialValue) {

     aggregatorHandler.registerReducer(name, reduceOp, globalInitialValue);

   }

   @Override

   public <R extends Writable> R getReduced(String name) {

     return aggregatorHandler.getReduced(name);

   }

   @Override

   public void broadcast(String name, Writable value) {

     aggregatorHandler.broadcast(name, value);

   }

   /**

    * Received partition stats from a worker

    *

    * @param partitionStats Partition stats

    */

   public void receivedPartitionStats(List<PartitionStats> partitionStats) {

     this.partitionStats.offer(partitionStats);

   }

   /**

    * Get all partition stats. Blocks until all workers have sent their stats

    *

    * @param numWorkers Number of workers to wait for

    * @param progressable Progressable to report progress to

    * @return All partition stats

    */

   public Iterable<PartitionStats> getAllPartitionStats(int numWorkers,

       Progressable progressable) {

     return Iterables.concat(

         partitionStats.getElements(numWorkers, progressable));

   }

 }