/*

  * 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.block_app.framework.piece.interfaces;

 import org.apache.giraph.graph.Vertex;

 import org.apache.giraph.writable.kryo.markers.NonKryoWritable;

 import org.apache.hadoop.io.Writable;

 import org.apache.hadoop.io.WritableComparable;

 /**

  * Interface representing actions that happen on worker, for each vertex,

  * during receive phase:

  * <ul>

  * <li> to receive messages from vertices </li>

  * <li> to receive data from master through aggregators </li>

  * </ul>

  *

  * Marked to not allow seriazliation, as it should be created on the worker,

  * so should never be serialiized, disallow only for catching problems early.

  *

  * @param <I> Vertex id type

  * @param <V> Vertex value type

  * @param <E> Edge value type

  * @param <M> Message type

  */

 @SuppressWarnings("rawtypes")

 public interface VertexReceiver<I extends WritableComparable,

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

     extends NonKryoWritable {

   /**

    * Must be defined by user to do computation on a single Vertex.

    *

    * @param vertex   Vertex

    * @param messages Messages that were sent to this vertex in the previous

    *                 superstep.  Each message is only guaranteed to have

    *                 a life expectancy as long as next() is not called.

    */

   void vertexReceive(Vertex<I, V, E> vertex, Iterable<M> messages);

 }