/*
* JBoss, Home of Professional Open Source
* Copyright 2011 Red Hat Inc. and/or its affiliates and other
* contributors as indicated by the @author tags. All rights reserved.
* See the copyright.txt in the distribution for a full listing of
* individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.infinispan.distexec.mapreduce;
import java.io.Serializable;
import java.util.Iterator;
/**
* Reduces intermediate key/value results from map phase of MapReduceTask. Infinispan distributed
* execution environment uses one instance of Reducer per execution node.
*
*
* @see Mapper
* @see MapReduceTask
*
* @author Manik Surtani
* @author Vladimir Blagojevic
* @author Sanne Grinovero
*
* @since 5.0
*/
public interface Reducer<KOut, VOut> extends Serializable {
/**
* Combines/reduces all intermediate values for a particular intermediate key to a single value.
* <p>
*
*/
VOut reduce(KOut reducedKey, Iterator<VOut> iter);
}