com.intel.hadoop.graphbuilder.preprocess.mapreduce.EdgeTransformMapper.java Source code

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Here is the source code for com.intel.hadoop.graphbuilder.preprocess.mapreduce.EdgeTransformMapper.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.preprocess.mapreduce;

import java.io.IOException;

import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MapReduceBase;
import org.apache.hadoop.mapred.Mapper;
import org.apache.hadoop.mapred.OutputCollector;
import org.apache.hadoop.mapred.Reporter;
import org.apache.log4j.Logger;

import com.intel.hadoop.graphbuilder.graph.Edge;
import com.intel.hadoop.graphbuilder.parser.FieldParser;
import com.intel.hadoop.graphbuilder.parser.GraphParser;
import com.intel.hadoop.graphbuilder.preprocess.mapreduce.keyvalue.PairListType;

/**
 * This Mapper class maps each edge (u,v,data) into (u, (v, data)) or (v, (u,
 * data)) based on {@code reduceEndPoint} parameter in the JobConf configured in
 * {@code EdgeTrandFormMR}.
 * 
 * 
 * @param <VidType>
 */
public class EdgeTransformMapper<VidType extends WritableComparable<VidType>> extends MapReduceBase
        implements Mapper<LongWritable, Text, VidType, PairListType> {

    private static final Logger LOG = Logger.getLogger(EdgeTransformMapper.class);

    @Override
    public void configure(JobConf job) {
        super.configure(job);
        this.reduceEndPoint = job.getBoolean("reduceEndPoint", EdgeTransformMR.SOURCE);
        try {
            this.graphparser = (GraphParser) Class.forName(job.get("GraphParser")).newInstance();
            this.vidparser = (FieldParser) Class.forName(job.get("VidParser")).newInstance();
            this.edataparser = (FieldParser) Class.forName(job.get("EdataParser")).newInstance();
            this.valClass = job.getMapOutputValueClass();
            val = (PairListType) valClass.newInstance();
        } catch (InstantiationException e) {
            e.printStackTrace();
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void map(LongWritable key, Text value, OutputCollector<VidType, PairListType> out, Reporter report)
            throws IOException {
        String line = value.toString();
        try {

            if (graphparser.isEdgeData(line)) {
                Edge e = graphparser.parseEdge(line, vidparser, edataparser);
                if (reduceEndPoint == EdgeTransformMR.SOURCE) {
                    val.init(e.target(), e.EdgeData());
                    out.collect((VidType) e.source(), val);
                } else {
                    val.init(e.source(), e.EdgeData());
                    out.collect((VidType) e.target(), val);
                }
            } else {
                LOG.error("Skip line: " + line);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    private PairListType val;
    private GraphParser graphparser;
    private FieldParser vidparser;
    private FieldParser edataparser;
    protected Class valClass;
    private boolean reduceEndPoint;
}