com.intel.hadoop.graphbuilder.partition.mapreduce.edge.EdgeIngressCombiner.java Source code

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Here is the source code for com.intel.hadoop.graphbuilder.partition.mapreduce.edge.EdgeIngressCombiner.java

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/* Copyright (C) 2012 Intel Corporation.
 *     All rights reserved.
 *           
 *  Licensed 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.
 *
 * For more about this software visit:
 *      http://www.01.org/GraphBuilder 
 */
package com.intel.hadoop.graphbuilder.partition.mapreduce.edge;

import java.io.IOException;
import java.util.Iterator;

import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reducer;
import org.apache.hadoop.mapred.Reporter;

import com.intel.hadoop.graphbuilder.partition.mapreduce.keyvalue.CombinedEdgeValueType;
import com.intel.hadoop.graphbuilder.partition.mapreduce.keyvalue.IngressKeyType;
import com.intel.hadoop.graphbuilder.partition.mapreduce.keyvalue.IngressValueType;

/**
 * Combines intermediate IngressValues.
 * 
 * @param <KeyType>
 * @param <ValType>
 */
public class EdgeIngressCombiner<KeyType extends IngressKeyType, ValType extends IngressValueType>
        extends MapReduceBase implements Reducer<KeyType, ValType, KeyType, ValType> {

    @Override
    public void configure(JobConf job) {
        super.configure(job);
        this.valClass = job.getMapOutputValueClass();
    }

    @Override
    public void reduce(KeyType key, Iterator<ValType> iter, OutputCollector<KeyType, ValType> out,
            Reporter reporter) throws IOException {
        if (!iter.hasNext()) {
            return;
        }

        ValType ret;
        try {
            ret = (ValType) valClass.newInstance();

            if (key.flag() == IngressKeyType.EDGEKEY) {
                CombinedEdgeValueType eval = ret.edgeValue();
                ret.reduce(IngressKeyType.EDGEKEY, iter);
                out.collect(key, ret);
            } else if (key.flag() == IngressKeyType.VERTEXKEY) {
                ret.reduce(IngressKeyType.VERTEXKEY, iter);
                out.collect(key, ret);
            }
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }

    }

    protected Class valClass;
}