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

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Here is the source code for com.intel.hadoop.graphbuilder.preprocess.mapreduce.CreateGraphMapper.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 java.util.Iterator;

import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
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.graph.Vertex;
import com.intel.hadoop.graphbuilder.preprocess.inputformat.GraphTokenizer;
import com.intel.hadoop.graphbuilder.preprocess.mapreduce.keyvalue.VertexEdgeUnionType;

/**
 * The Mapper class parses each input value provided by the {@code InputFormat},
 * and outputs a list of {@code Vertex} and a list of {@code Edge} using a
 * {@code GraphTokenizer}.
 * 
 */
public class CreateGraphMapper extends MapReduceBase
        implements Mapper<LongWritable, Text, IntWritable, VertexEdgeUnionType> {

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

    @Override
    public void configure(JobConf job) {
        super.configure(job);
        try {
            this.tokenizer = (GraphTokenizer) Class.forName(job.get("GraphTokenizer")).newInstance();
            tokenizer.configure(job);
            this.valClass = job.getMapOutputValueClass();
            mapVal = (VertexEdgeUnionType) 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<IntWritable, VertexEdgeUnionType> out,
            Reporter arg3) throws IOException {

        tokenizer.parse(value.toString());
        Iterator<Edge> eiter = tokenizer.getEdges();
        Iterator<Vertex> viter = tokenizer.getVertices();
        try {

            while (eiter.hasNext()) {
                Edge e = eiter.next();
                mapVal.init(VertexEdgeUnionType.EDGEVAL, e);
                out.collect(new IntWritable(e.hashCode()), mapVal);
            }

            while (viter.hasNext()) {
                Vertex v = viter.next();
                mapVal.init(VertexEdgeUnionType.VERTEXVAL, v);
                out.collect(new IntWritable(v.hashCode()), mapVal);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private VertexEdgeUnionType mapVal;
    private GraphTokenizer tokenizer;
    protected Class valClass;
}