/*

  * 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.comm.requests;

 import java.io.DataInput;

 import java.io.DataOutput;

 import java.io.IOException;

 import org.apache.giraph.comm.ServerData;

 import org.apache.giraph.utils.ByteArrayVertexIdMessages;

 import org.apache.hadoop.io.Writable;

 import org.apache.hadoop.io.WritableComparable;

 /**

  * Send a collection of vertex messages for a partition. It adds messages to

  * current message store and it should be used only during partition exchange.

  *

  * @param <I> Vertex id

  * @param <V> Vertex data

  * @param <E> Edge data

  * @param <M> Message data

  */

 public class SendPartitionCurrentMessagesRequest<I extends WritableComparable,

   V extends Writable, E extends Writable, M extends Writable> extends

   WritableRequest<I, V, E> implements WorkerRequest<I, V, E> {

   /** Destination partition for these vertices' messages*/

   private int partitionId;

   /** Map of destination vertex ID's to message lists */

   private ByteArrayVertexIdMessages<I, M> vertexIdMessageMap;

   /** Constructor used for reflection only */

   public SendPartitionCurrentMessagesRequest() { }

   /**

    * Constructor used to send request.

    *

    * @param partitionId Partition to send the request to

    * @param vertexIdMessages Map of messages to send

    */

   public SendPartitionCurrentMessagesRequest(int partitionId,

     ByteArrayVertexIdMessages<I, M> vertexIdMessages) {

     super();

     this.partitionId = partitionId;

     this.vertexIdMessageMap = vertexIdMessages;

   }

   @Override

   public RequestType getType() {

     return RequestType.SEND_PARTITION_CURRENT_MESSAGES_REQUEST;

   }

   @Override

   public void readFieldsRequest(DataInput input) throws IOException {

     partitionId = input.readInt();

     // At this moment the Computation class have already been replaced with

     // the new one, and we deal with messages from previous superstep

     vertexIdMessageMap = new ByteArrayVertexIdMessages<>(

         getConf().<M>createIncomingMessageValueFactory());

     vertexIdMessageMap.setConf(getConf());

     vertexIdMessageMap.initialize();

     vertexIdMessageMap.readFields(input);

   }

   @Override

   public void writeRequest(DataOutput output) throws IOException {

     output.writeInt(partitionId);

     vertexIdMessageMap.write(output);

   }

   @Override

   public void doRequest(ServerData<I, V, E> serverData) {

     serverData.<M>getCurrentMessageStore().addPartitionMessages(partitionId,

         vertexIdMessageMap);

   }

   @Override

   public int getSerializedSize() {

     return super.getSerializedSize() + 4 +

         vertexIdMessageMap.getSerializedSize();

   }

 }