/*

  * 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.combiner;

 import org.apache.hadoop.io.DoubleWritable;

 import org.apache.hadoop.io.WritableComparable;

 /**

  * MessageCombiner which finds the minimum of {@link DoubleWritable}.

  */

 public class MinimumDoubleMessageCombiner

     implements MessageCombiner<WritableComparable, DoubleWritable> {

   @Override

   public void combine(WritableComparable vertexIndex,

       DoubleWritable originalMessage, DoubleWritable messageToCombine) {

     if (originalMessage.get() > messageToCombine.get()) {

       originalMessage.set(messageToCombine.get());

     }

   }

   @Override

   public DoubleWritable createInitialMessage() {

     return new DoubleWritable(Double.MAX_VALUE);

   }

 }