nl.tudelft.graphalytics.mapreducev2.evo.UndirectedForestFireModelJob.java Source code

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Here is the source code for nl.tudelft.graphalytics.mapreducev2.evo.UndirectedForestFireModelJob.java

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/**
 * Copyright 2015 Delft University of Technology
 *
 * 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.
 */
package nl.tudelft.graphalytics.mapreducev2.evo;

import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.NullWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.*;
import nl.tudelft.graphalytics.domain.algorithms.ForestFireModelParameters;
import nl.tudelft.graphalytics.mapreducev2.MapReduceJob;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Job specification for forest fire model on MapReduce version 2 for undirected graphs.
 *
 * @author Tim Hegeman
 */
public class UndirectedForestFireModelJob extends MapReduceJob<ForestFireModelParameters> {

    private Map<LongWritable, List<LongWritable>> burnedEdges;

    public UndirectedForestFireModelJob(String inputPath, String intermediatePath, String outputPath,
            ForestFireModelParameters parameters) {
        super(inputPath, intermediatePath, outputPath, parameters);
        burnedEdges = new HashMap<>();
    }

    @Override
    protected Class<?> getMapOutputKeyClass() {
        return LongWritable.class;
    }

    @Override
    protected Class<?> getMapOutputValueClass() {
        return Text.class;
    }

    @Override
    protected Class<?> getOutputKeyClass() {
        return NullWritable.class;
    }

    @Override
    protected Class<?> getOutputValueClass() {
        return Text.class;
    }

    @SuppressWarnings("rawtypes")
    @Override
    protected Class<? extends InputFormat> getInputFormatClass() {
        return TextInputFormat.class;
    }

    @SuppressWarnings("rawtypes")
    @Override
    protected Class<? extends OutputFormat> getOutputFormatClass() {
        return TextOutputFormat.class;
    }

    @SuppressWarnings("rawtypes")
    @Override
    protected Class<? extends Mapper> getMapperClass() {
        return UndirectedForestFireModelMap.class;
    }

    @SuppressWarnings("rawtypes")
    @Override
    protected Class<? extends Reducer> getReducerClass() {
        return UndirectedForestFireModelReducer.class;
    }

    @Override
    protected boolean isFinished() {
        return (getIteration() > getParameters().getMaxIterations() + 1
                || (getIteration() > 0 && burnedEdges.isEmpty()));
    }

    @Override
    protected void setConfigurationParameters(JobConf jobConfiguration) {
        super.setConfigurationParameters(jobConfiguration);
        jobConfiguration.setLong(ForestFireModelUtils.MAX_ID, getParameters().getMaxId() + 1);
        jobConfiguration.setFloat(ForestFireModelUtils.P_RATIO, getParameters().getPRatio());
        jobConfiguration.setFloat(ForestFireModelUtils.R_RATIO, getParameters().getRRatio());
        jobConfiguration.set(ForestFireModelUtils.CURRENT_AMBASSADORS,
                ForestFireModelUtils.verticesIDsMap2String(burnedEdges));

        if (getIteration() == 1) {
            if (getNumMappers() > 0) {
                jobConfiguration.setInt(ForestFireModelUtils.NEW_VERTICES_NR,
                        getParameters().getNumNewVertices() / getNumMappers());
                jobConfiguration.setInt(ForestFireModelUtils.ID_SHIFT, getNumMappers());
            } else {
                jobConfiguration.setInt(ForestFireModelUtils.NEW_VERTICES_NR, getParameters().getNumNewVertices());
                jobConfiguration.setInt(ForestFireModelUtils.ID_SHIFT, 1024 * 1024);
            }
            jobConfiguration.setBoolean(ForestFireModelUtils.IS_INIT, true);
        } else if (getIteration() == getParameters().getMaxIterations() + 1) {
            jobConfiguration.setBoolean(ForestFireModelUtils.IS_FINAL, true);
        }
    }

    @Override
    protected void processJobOutput(RunningJob jobExecution) throws IOException {
        Counters counters = jobExecution.getCounters();
        Counters.Group burned = counters.getGroup(ForestFireModelUtils.NEW_VERTICES);
        burnedEdges.clear(); // clean previous iteration data
        for (Counters.Counter counter : burned) {
            String data[] = counter.getName().split(",");
            String newVertex = data[0];
            LongWritable newVertexLong = new LongWritable(Long.parseLong(newVertex));
            String ambassador = data[1];
            LongWritable ambassadorLong = new LongWritable(Long.parseLong(ambassador));

            List<LongWritable> ambassadors = (burnedEdges.containsKey(newVertexLong)
                    ? burnedEdges.get(newVertexLong)
                    : new ArrayList<LongWritable>());
            ambassadors.add(ambassadorLong);
            burnedEdges.put(newVertexLong, ambassadors);
        }

        System.out.println("\n************************************");
        System.out.println("* FFM Hoops " + getIteration() + " FINISHED *");
        System.out.println("************************************\n");
    }

}