Example usage for org.apache.hadoop.mapred JobConf setMapperClass

List of usage examples for org.apache.hadoop.mapred JobConf setMapperClass

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Introduction

In this page you can find the example usage for org.apache.hadoop.mapred JobConf setMapperClass.

Prototype

public void setMapperClass(Class<? extends Mapper> theClass)

Source Link

Document

Set the Mapper class for the job.

Usage

From source file:edu.umd.cloud9.pagerank.FindMaxPageRankNodes.java

License:Apache License

/**
 * Runs this tool.//from   www.  ja  v  a  2s. c  o m
 */
public int run(String[] args) throws Exception {
    if (args.length != 3) {
        printUsage();
        return -1;
    }

    String inputPath = args[0];
    String outputPath = args[1];
    int n = Integer.parseInt(args[2]);

    sLogger.info("Tool name: FindMaxPageRankNodes");
    sLogger.info(" - input: " + inputPath);
    sLogger.info(" - output: " + outputPath);
    sLogger.info(" - n: " + n);

    JobConf conf = new JobConf(FindMaxPageRankNodes.class);
    conf.setJobName("FindMaxPageRankNodes");

    conf.setNumMapTasks(1);
    conf.setNumReduceTasks(1);

    conf.setInt("mapred.min.split.size", 1024 * 1024 * 1024);
    conf.setInt("n", n);

    FileInputFormat.addInputPath(conf, new Path(inputPath));
    FileOutputFormat.setOutputPath(conf, new Path(outputPath));

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(TextOutputFormat.class);

    conf.setMapOutputKeyClass(IntWritable.class);
    conf.setMapOutputValueClass(FloatWritable.class);

    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(FloatWritable.class);

    conf.setMapperClass(MyMapper.class);
    conf.setReducerClass(MyReducer.class);

    // delete the output directory if it exists already
    FileSystem.get(conf).delete(new Path(outputPath), true);

    JobClient.runJob(conf);

    return 0;
}

From source file:edu.umd.cloud9.pagerank.PartitionGraph.java

License:Apache License

public int run(String[] args) throws IOException {
    if (args.length != 5) {
        printUsage();//from   ww w . j  a v  a2  s. c  om
        return -1;
    }

    String inPath = args[0];
    String outPath = args[1];
    int numParts = Integer.parseInt(args[2]);
    boolean useRange = Integer.parseInt(args[3]) != 0;
    int nodeCount = Integer.parseInt(args[4]);

    sLogger.info("Tool name: PartitionGraph");
    sLogger.info(" - inputDir: " + inPath);
    sLogger.info(" - outputDir: " + outPath);
    sLogger.info(" - numPartitions: " + numParts);
    sLogger.info(" - useRange?: " + useRange);
    sLogger.info(" - nodeCnt: " + nodeCount);

    JobConf conf = new JobConf(PartitionGraph.class);

    conf.setJobName("Partition Graph " + numParts);
    conf.setNumReduceTasks(numParts);

    conf.setInt("mapred.min.split.size", 1024 * 1024 * 1024);
    conf.set("mapred.child.java.opts", "-Xmx2048m");
    conf.setInt("NodeCount", nodeCount);

    FileInputFormat.setInputPaths(conf, new Path(inPath));
    FileOutputFormat.setOutputPath(conf, new Path(outPath));

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);

    conf.setMapOutputKeyClass(IntWritable.class);
    conf.setMapOutputValueClass(PageRankNode.class);

    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(PageRankNode.class);

    conf.setMapperClass(MapClass.class);
    conf.setReducerClass(ReduceClass.class);

    conf.setSpeculativeExecution(false);

    if (useRange) {
        conf.setPartitionerClass(RangePartitioner.class);
    }

    FileSystem.get(conf).delete(new Path(outPath), true);

    JobClient.runJob(conf);

    return 0;
}

From source file:edu.umd.cloud9.pagerank.RunPageRankBasic.java

License:Apache License

private float phase1(String path, int i, int j, int n, boolean useCombiner, boolean useInmapCombiner,
        boolean useRange) throws IOException {
    JobConf conf = new JobConf(RunPageRankBasic.class);

    String in = path + "/iter" + sFormat.format(i);
    String out = path + "/iter" + sFormat.format(j) + "t";
    String outm = out + "-mass";

    // we need to actually count the number of part files to get the number
    // of partitions (because the directory might contain _log)
    int numPartitions = 0;
    for (FileStatus s : FileSystem.get(conf).listStatus(new Path(in))) {
        if (s.getPath().getName().contains("part-"))
            numPartitions++;//from  w w  w  . j a  v  a  2 s  .  c o  m
    }

    sLogger.info("PageRank: iteration " + j + ": Phase1");
    sLogger.info(" - input: " + in);
    sLogger.info(" - output: " + out);
    sLogger.info(" - nodeCnt: " + n);
    sLogger.info(" - useCombiner: " + useCombiner);
    sLogger.info(" - useInmapCombiner: " + useInmapCombiner);
    sLogger.info(" - useRange: " + useRange);
    sLogger.info("computed number of partitions: " + numPartitions);

    int numMapTasks = numPartitions;
    int numReduceTasks = numPartitions;

    conf.setJobName("PageRank:Basic:iteration" + j + ":Phase1");
    conf.setInt("NodeCount", n);

    conf.setNumMapTasks(numMapTasks);
    conf.setNumReduceTasks(numReduceTasks);

    conf.setInt("mapred.min.split.size", 1024 * 1024 * 1024);
    conf.set("mapred.child.java.opts", "-Xmx2048m");

    conf.set("PageRankMassPath", outm);

    FileInputFormat.setInputPaths(conf, new Path(in));
    FileOutputFormat.setOutputPath(conf, new Path(out));

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);

    conf.setMapOutputKeyClass(IntWritable.class);
    conf.setMapOutputValueClass(PageRankNode.class);

    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(PageRankNode.class);

    if (useInmapCombiner) {
        conf.setMapperClass(MapWithInMapperCombiningClass.class);
    } else {
        conf.setMapperClass(MapClass.class);
    }

    if (useCombiner) {
        conf.setCombinerClass(CombineClass.class);
    }

    if (useRange) {
        conf.setPartitionerClass(RangePartitioner.class);
    }

    conf.setReducerClass(ReduceClass.class);

    conf.setSpeculativeExecution(false);

    FileSystem.get(conf).delete(new Path(out), true);
    FileSystem.get(conf).delete(new Path(outm), true);

    JobClient.runJob(conf);

    float mass = Float.NEGATIVE_INFINITY;
    FileSystem fs = FileSystem.get(conf);
    for (FileStatus f : fs.listStatus(new Path(outm))) {
        FSDataInputStream fin = fs.open(f.getPath());
        mass = sumLogProbs(mass, fin.readFloat());
        fin.close();
    }

    return mass;
}

From source file:edu.umd.cloud9.pagerank.RunPageRankBasic.java

License:Apache License

private void phase2(String path, int i, int j, int n, float missing) throws IOException {
    JobConf conf = new JobConf(RunPageRankBasic.class);

    sLogger.info("missing PageRank mass: " + missing);
    sLogger.info("number of nodes: " + n);

    String in = path + "/iter" + sFormat.format(j) + "t";
    String out = path + "/iter" + sFormat.format(j);

    sLogger.info("PageRank: iteration " + j + ": Phase2");
    sLogger.info(" - input: " + in);
    sLogger.info(" - output: " + out);

    int numMapTasks = FileSystem.get(conf).listStatus(new Path(in)).length;
    int numReduceTasks = 0;

    conf.setJobName("PageRank:Basic:iteration" + j + ":Phase2");
    conf.setInt("mapred.min.split.size", 1024 * 1024 * 1024);
    conf.setFloat("MissingMass", (float) missing);
    conf.setInt("NodeCount", n);

    conf.setNumMapTasks(numMapTasks);/* w w w. jav  a  2  s  .c o m*/
    conf.setNumReduceTasks(numReduceTasks);

    FileInputFormat.setInputPaths(conf, new Path(in));
    FileOutputFormat.setOutputPath(conf, new Path(out));

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);

    conf.setMapOutputKeyClass(IntWritable.class);
    conf.setMapOutputValueClass(PageRankNode.class);

    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(PageRankNode.class);

    conf.setMapperClass(MapPageRankMassDistributionClass.class);
    conf.setCombinerClass(IdentityReducer.class);
    conf.setReducerClass(IdentityReducer.class);

    FileSystem.get(conf).delete(new Path(out), true);

    JobClient.runJob(conf);
}

From source file:edu.umd.cloud9.pagerank.RunPageRankSchimmy.java

License:Apache License

private float phase1(String path, int i, int j, int n, boolean useCombiner, boolean useInmapCombiner,
        boolean useRange) throws IOException {
    JobConf conf = new JobConf(RunPageRankBasic.class);

    String in = path + "/iter" + sFormat.format(i);
    String out = path + "/iter" + sFormat.format(j) + "t";
    String outm = out + "-mass";

    FileSystem fs = FileSystem.get(conf);

    // we need to actually count the number of part files to get the number
    // of partitions (because the directory might contain _log)
    int numPartitions = 0;
    for (FileStatus s : FileSystem.get(conf).listStatus(new Path(in))) {
        if (s.getPath().getName().contains("part-"))
            numPartitions++;/*from   ww w  .j a v  a 2 s .  c o m*/
    }

    conf.setInt("NodeCount", n);

    Partitioner p = null;

    if (useRange) {
        p = new RangePartitioner<IntWritable, Writable>();
        p.configure(conf);
    } else {
        p = new HashPartitioner<WritableComparable, Writable>();
    }

    // this is really annoying: the mapping between the partition numbers on
    // disk (i.e., part-XXXX) and what partition the file contains (i.e.,
    // key.hash % #reducer) is arbitrary... so this means that we need to
    // open up each partition, peek inside to find out.
    IntWritable key = new IntWritable();
    PageRankNode value = new PageRankNode();
    FileStatus[] status = fs.listStatus(new Path(in));

    StringBuilder sb = new StringBuilder();

    for (FileStatus f : status) {
        if (f.getPath().getName().contains("_logs"))
            continue;

        SequenceFile.Reader reader = new SequenceFile.Reader(fs, f.getPath(), conf);

        reader.next(key, value);
        int np = p.getPartition(key, value, numPartitions);
        reader.close();

        sLogger.info(f.getPath() + "\t" + np);
        sb.append(np + "=" + f.getPath() + "\t");
    }

    sLogger.info(sb.toString().trim());

    sLogger.info("PageRankSchimmy: iteration " + j + ": Phase1");
    sLogger.info(" - input: " + in);
    sLogger.info(" - output: " + out);
    sLogger.info(" - nodeCnt: " + n);
    sLogger.info(" - useCombiner: " + useCombiner);
    sLogger.info(" - useInmapCombiner: " + useInmapCombiner);
    sLogger.info(" - numPartitions: " + numPartitions);
    sLogger.info(" - useRange: " + useRange);
    sLogger.info("computed number of partitions: " + numPartitions);

    int numMapTasks = numPartitions;
    int numReduceTasks = numPartitions;

    conf.setJobName("PageRankSchimmy:iteration" + j + ":Phase1");

    conf.setNumMapTasks(numMapTasks);
    conf.setNumReduceTasks(numReduceTasks);

    conf.setInt("mapred.min.split.size", 1024 * 1024 * 1024);
    conf.set("mapred.child.java.opts", "-Xmx2048m");

    conf.set("PageRankMassPath", outm);
    conf.set("BasePath", in);
    conf.set("PartitionMapping", sb.toString().trim());

    FileInputFormat.setInputPaths(conf, new Path(in));
    FileOutputFormat.setOutputPath(conf, new Path(out));

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);

    conf.setMapOutputKeyClass(IntWritable.class);
    conf.setMapOutputValueClass(FloatWritable.class);

    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(PageRankNode.class);

    if (useInmapCombiner) {
        conf.setMapperClass(MapWithInMapperCombiningClass.class);
    } else {
        conf.setMapperClass(MapClass.class);
    }

    if (useCombiner) {
        conf.setCombinerClass(CombineClass.class);
    }

    if (useRange) {
        conf.setPartitionerClass(RangePartitioner.class);
    }

    conf.setReducerClass(ReduceClass.class);

    conf.setSpeculativeExecution(false);

    FileSystem.get(conf).delete(new Path(out), true);
    FileSystem.get(conf).delete(new Path(outm), true);

    JobClient.runJob(conf);

    float mass = Float.NEGATIVE_INFINITY;
    for (FileStatus f : fs.listStatus(new Path(outm))) {
        FSDataInputStream fin = fs.open(f.getPath());
        mass = sumLogProbs(mass, fin.readFloat());
        fin.close();
    }

    return mass;
}

From source file:edu.umd.cloud9.pagerank.RunPageRankSchimmy.java

License:Apache License

private void phase2(String path, int i, int j, int n, float missing) throws IOException {
    JobConf conf = new JobConf(RunPageRankBasic.class);

    sLogger.info("missing PageRank mass: " + missing);
    sLogger.info("number of nodes: " + n);

    String in = path + "/iter" + sFormat.format(j) + "t";
    String out = path + "/iter" + sFormat.format(j);

    sLogger.info("PageRankSchimmy: iteration " + j + ": Phase2");
    sLogger.info(" - input: " + in);
    sLogger.info(" - output: " + out);

    int numMapTasks = FileSystem.get(conf).listStatus(new Path(in)).length;
    int numReduceTasks = 0;

    conf.setJobName("PageRankSchimmy:iteration" + j + ":Phase2");
    conf.setInt("mapred.min.split.size", 1024 * 1024 * 1024);

    conf.setNumMapTasks(numMapTasks);//from  w  w  w  .java  2  s . c  o m
    conf.setNumReduceTasks(numReduceTasks);

    FileInputFormat.setInputPaths(conf, new Path(in));
    FileOutputFormat.setOutputPath(conf, new Path(out));

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);

    conf.setMapOutputKeyClass(IntWritable.class);
    conf.setMapOutputValueClass(PageRankNode.class);

    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(PageRankNode.class);

    conf.setMapperClass(MapPageRankMassDistributionClass.class);
    conf.setCombinerClass(IdentityReducer.class);
    conf.setReducerClass(IdentityReducer.class);

    conf.setFloat("MissingMass", (float) missing);
    conf.setInt("NodeCount", n);

    FileSystem.get(conf).delete(new Path(out), true);

    JobClient.runJob(conf);
}

From source file:edu.umd.cloud9.webgraph.BuildReverseWebGraph.java

License:Apache License

public int runTool() throws Exception {
    JobConf conf = new JobConf(getConf(), BuildReverseWebGraph.class);
    FileSystem fs = FileSystem.get(conf);

    int numMappers = conf.getInt("Cloud9.Mappers", 1);
    int numReducers = conf.getInt("Cloud9.Reducers", 200);

    String inputPath = conf.get("Cloud9.InputPath");
    String outputPath = conf.get("Cloud9.OutputPath");

    conf.setJobName("ReverseWebGraph");
    conf.set("mapred.child.java.opts", "-Xmx2048m");
    conf.setInt("mapred.task.timeout", 60000000);
    conf.set("mapreduce.map.memory.mb", "2048");
    conf.set("mapreduce.map.java.opts", "-Xmx2048m");
    conf.set("mapreduce.reduce.memory.mb", "2048");
    conf.set("mapreduce.reduce.java.opts", "-Xmx2048m");
    conf.set("mapreduce.task.timeout", "60000000");

    conf.setNumMapTasks(numMappers);/*  w  ww. j a  va2s .c om*/
    conf.setNumReduceTasks(numReducers);
    conf.setMapperClass(IdentityMapper.class);
    conf.setReducerClass(Reduce.class);
    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(ArrayListWritable.class);
    conf.setMapOutputKeyClass(Text.class);
    conf.setMapOutputValueClass(ArrayListWritable.class);

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);

    SequenceFileOutputFormat.setCompressOutput(conf, true);
    SequenceFileOutputFormat.setOutputCompressionType(conf, SequenceFile.CompressionType.BLOCK);

    SequenceFileInputFormat.setInputPaths(conf, inputPath);
    FileOutputFormat.setOutputPath(conf, new Path(outputPath));

    LOG.info("BuildReverseWebGraph");
    LOG.info(" - input path: " + inputPath);
    LOG.info(" - output path: " + outputPath);

    if (!fs.exists(new Path(outputPath))) {
        JobClient.runJob(conf);
    } else {
        LOG.info(outputPath + " already exists! Skipping this step...");
    }

    return 0;
}

From source file:edu.umd.cloud9.webgraph.BuildWebGraph.java

License:Apache License

public int runTool() throws Exception {
    JobConf conf = new JobConf(getConf(), BuildWebGraph.class);
    FileSystem fs = FileSystem.get(conf);

    int numMappers = conf.getInt("Cloud9.Mappers", 1);
    int numReducers = conf.getInt("Cloud9.Reducers", 200);

    String inputPath = conf.get("Cloud9.InputPath");
    String outputPath = conf.get("Cloud9.OutputPath");

    conf.setJobName("ConstructWebGraph");
    conf.set("mapred.child.java.opts", "-Xmx2048m");
    conf.setInt("mapred.task.timeout", 60000000);
    conf.set("mapreduce.map.memory.mb", "2048");
    conf.set("mapreduce.map.java.opts", "-Xmx2048m");
    conf.set("mapreduce.reduce.memory.mb", "2048");
    conf.set("mapreduce.reduce.java.opts", "-Xmx2048m");
    conf.set("mapreduce.task.timeout", "60000000");

    conf.setNumMapTasks(numMappers);/*from   www . j av a 2 s .  c o m*/
    conf.setNumReduceTasks(numReducers);

    conf.setMapperClass(Map.class);
    conf.setReducerClass(Reduce.class);

    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(ArrayListWritable.class);

    conf.setMapOutputKeyClass(IntWritable.class);
    conf.setMapOutputValueClass(ArrayListWritable.class);

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);

    SequenceFileOutputFormat.setCompressOutput(conf, true);
    SequenceFileOutputFormat.setOutputCompressionType(conf, SequenceFile.CompressionType.BLOCK);

    SequenceFileInputFormat.setInputPaths(conf, inputPath);
    FileOutputFormat.setOutputPath(conf, new Path(outputPath));

    LOG.info("BuildWebGraph");
    LOG.info(" - input path: " + inputPath);
    LOG.info(" - output path: " + outputPath);

    if (!fs.exists(new Path(outputPath))) {
        JobClient.runJob(conf);
    } else {
        LOG.info(outputPath + " already exists! Skipping this step...");
    }

    return 0;
}

From source file:edu.umd.cloud9.webgraph.ClueExtractLinks.java

License:Apache License

public int runTool() throws Exception {
    JobConf conf = new JobConf(getConf(), ClueExtractLinks.class);
    FileSystem fs = FileSystem.get(conf);

    int numMappers = conf.getInt("Cloud9.Mappers", 1);
    int numReducers = conf.getInt("Cloud9.Reducers", 200);

    String inputPath = conf.get("Cloud9.InputPath");
    String outputPath = conf.get("Cloud9.OutputPath");
    String mappingFile = conf.get("Cloud9.DocnoMappingFile");

    if (!fs.exists(new Path(mappingFile))) {
        throw new RuntimeException("Error: Docno mapping data file " + mappingFile + " doesn't exist!");
    }/*from w  w w.j  a  v  a2  s. c  o m*/

    DistributedCache.addCacheFile(new URI(mappingFile), conf);

    conf.setJobName("ClueExtractLinks");
    conf.set("mapred.child.java.opts", "-Xmx2048m");
    conf.setInt("mapred.task.timeout", 60000000);
    conf.set("mapreduce.map.memory.mb", "2048");
    conf.set("mapreduce.map.java.opts", "-Xmx2048m");
    conf.set("mapreduce.reduce.memory.mb", "2048");
    conf.set("mapreduce.reduce.java.opts", "-Xmx2048m");
    conf.set("mapreduce.task.timeout", "60000000");

    conf.setNumMapTasks(numMappers);
    conf.setNumReduceTasks(numReducers);
    // TODO: to read!!
    conf.setMapperClass(Map.class);
    conf.setCombinerClass(Reduce.class);
    conf.setReducerClass(Reduce.class);
    conf.setOutputKeyClass(Text.class);
    conf.setOutputValueClass(ArrayListWritable.class);
    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);
    SequenceFileOutputFormat.setCompressOutput(conf, true);
    SequenceFileOutputFormat.setOutputCompressionType(conf, SequenceFile.CompressionType.BLOCK);
    SequenceFileInputFormat.setInputPaths(conf, inputPath);
    FileOutputFormat.setOutputPath(conf, new Path(outputPath));

    LOG.info("ClueExtractLinks");
    LOG.info(" - input path: " + inputPath);
    LOG.info(" - output path: " + outputPath);
    LOG.info(" - mapping file: " + mappingFile);
    LOG.info(" - include internal links? " + conf.getBoolean("Cloud9.IncludeInternalLinks", false));

    if (!fs.exists(new Path(outputPath))) {
        JobClient.runJob(conf);
    } else {
        LOG.info(outputPath + " already exists! Skipping this step...");
    }
    return 0;
}

From source file:edu.umd.cloud9.webgraph.CollectHostnames.java

License:Apache License

public int runTool() throws Exception {

    JobConf conf = new JobConf(getConf(), CollectHostnames.class);
    FileSystem fs = FileSystem.get(conf);

    int numMappers = conf.getInt("Cloud9.Mappers", 1);
    int numReducers = conf.getInt("Cloud9.Reducers", 200);

    String inputPath = conf.get("Cloud9.InputPath");
    String outputPath = conf.get("Cloud9.OutputPath");

    conf.setJobName("CollectHostnames");
    conf.set("mapred.child.java.opts", "-Xmx4096m");
    conf.setInt("mapred.task.timeout", 60000000);

    conf.setNumMapTasks(numMappers);//from  w  ww .  j av a2 s  .  c om
    conf.setNumReduceTasks(numReducers);

    conf.setMapperClass(Map.class);
    conf.setPartitionerClass(Partition.class);
    conf.setReducerClass(Reduce.class);

    conf.setOutputKeyClass(IntWritable.class);
    conf.setOutputValueClass(ArrayListWritable.class);

    conf.setMapOutputKeyClass(PairOfIntString.class);
    conf.setMapOutputValueClass(IntWritable.class);

    conf.setInputFormat(SequenceFileInputFormat.class);
    conf.setOutputFormat(SequenceFileOutputFormat.class);

    SequenceFileOutputFormat.setCompressOutput(conf, true);
    SequenceFileOutputFormat.setOutputCompressionType(conf, SequenceFile.CompressionType.BLOCK);

    SequenceFileInputFormat.setInputPaths(conf, inputPath);
    FileOutputFormat.setOutputPath(conf, new Path(outputPath));

    sLogger.info("PropagateHostname");
    sLogger.info(" - input path: " + inputPath);
    sLogger.info(" - output path: " + outputPath);

    if (!fs.exists(new Path(outputPath))) {
        JobClient.runJob(conf);
    } else {
        sLogger.info(outputPath + " already exists! Skipping this step...");
    }

    return 0;
}