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

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

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Introduction

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

Prototype

public void setReducerClass(Class<? extends Reducer> theClass)

Source Link

Document

Set the Reducer class for the job.

Usage

From source file:com.benchmark.mapred.PiEstimator.java

License:Apache License

/**
 * Run a map/reduce job for estimating Pi.
 *
 * @return the estimated value of Pi//from  w  ww.  ja v a2 s . co  m
 */
public static BigDecimal estimate(int numMaps, long numPoints, JobConf jobConf) throws IOException {
    //setup job conf
    jobConf.setJobName(PiEstimator.class.getSimpleName());

    jobConf.setInputFormat(SequenceFileInputFormat.class);

    jobConf.setOutputKeyClass(BooleanWritable.class);
    jobConf.setOutputValueClass(LongWritable.class);
    jobConf.setOutputFormat(SequenceFileOutputFormat.class);

    jobConf.setMapperClass(PiMapper.class);
    jobConf.setNumMapTasks(numMaps);

    jobConf.setReducerClass(PiReducer.class);
    jobConf.setNumReduceTasks(1);

    // turn off speculative execution, because DFS doesn't handle
    // multiple writers to the same file.
    jobConf.setSpeculativeExecution(false);

    //setup input/output directories
    //final Path inDir = new Path(TMP_DIR, "in");
    final Path inDir = new Path("/home/hadoop1/tmp_dir", "in");
    System.out.println("inDir =" + inDir.toString());
    //final Path outDir = new Path(TMP_DIR, "out");
    final Path outDir = new Path("/home/hadoop1/tmp_dir", "out");
    System.out.println("outDir =" + outDir.toString());
    FileInputFormat.setInputPaths(jobConf, inDir);
    FileOutputFormat.setOutputPath(jobConf, outDir);

    final FileSystem fs = FileSystem.get(jobConf);
    if (fs.exists(TMP_DIR)) {
        throw new IOException(
                "Tmp directory " + fs.makeQualified(TMP_DIR) + " already exists.  Please remove it first.");
    }
    if (!fs.mkdirs(inDir)) {
        throw new IOException("Cannot create input directory " + inDir);
    }

    try {
        //generate an input file for each map task
        for (int i = 0; i < numMaps; ++i) {
            final Path file = new Path(inDir, "part" + i);
            final LongWritable offset = new LongWritable(i * numPoints);
            final LongWritable size = new LongWritable(numPoints);
            final SequenceFile.Writer writer = SequenceFile.createWriter(fs, jobConf, file, LongWritable.class,
                    LongWritable.class, CompressionType.NONE);
            try {
                writer.append(offset, size);
            } finally {
                writer.close();
            }
            System.out.println("Wrote input for Map #" + i);
        }

        //start a map/reduce job
        System.out.println("Starting Job");
        final long startTime = System.currentTimeMillis();
        JobClient.runJob(jobConf);
        final double duration = (System.currentTimeMillis() - startTime) / 1000.0;
        System.out.println("Job Finished in " + duration + " seconds");

        //read outputs
        Path inFile = new Path(outDir, "reduce-out");
        LongWritable numInside = new LongWritable();
        LongWritable numOutside = new LongWritable();
        SequenceFile.Reader reader = new SequenceFile.Reader(fs, inFile, jobConf);
        try {
            reader.next(numInside, numOutside);
        } finally {
            reader.close();
        }

        //compute estimated value
        return BigDecimal.valueOf(4).setScale(20).multiply(BigDecimal.valueOf(numInside.get()))
                .divide(BigDecimal.valueOf(numMaps)).divide(BigDecimal.valueOf(numPoints));
    } finally {
        fs.delete(TMP_DIR, true);
    }
}

From source file:com.benchmark.mapred.RandomWriter.java

License:Apache License

/**
 * This is the main routine for launching a distributed random write job.
 * It runs 10 maps/node and each node writes 1 gig of data to a DFS file.
 * The reduce doesn't do anything./* www. j a  va  2s.  c om*/
 * 
 * @throws IOException 
 */
public int run(String[] args) throws Exception {
    if (args.length == 0) {
        System.out.println("Usage: writer <out-dir>");
        ToolRunner.printGenericCommandUsage(System.out);
        return -1;
    }

    Path outDir = new Path(args[0]);
    JobConf job = new JobConf(getConf());

    job.setJarByClass(RandomWriter.class);
    job.setJobName("random-writer");
    FileOutputFormat.setOutputPath(job, outDir);

    job.setOutputKeyClass(BytesWritable.class);
    job.setOutputValueClass(BytesWritable.class);

    job.setInputFormat(RandomInputFormat.class);
    job.setMapperClass(Map.class);
    job.setReducerClass(IdentityReducer.class);
    job.setOutputFormat(SequenceFileOutputFormat.class);

    JobClient client = new JobClient(job);
    ClusterStatus cluster = client.getClusterStatus();
    int numMapsPerHost = job.getInt("test.randomwriter.maps_per_host", 10);
    long numBytesToWritePerMap = job.getLong("test.randomwrite.bytes_per_map", 1 * 1024 * 1024 * 1024);
    if (numBytesToWritePerMap == 0) {
        System.err.println("Cannot have test.randomwrite.bytes_per_map set to 0");
        return -2;
    }
    long totalBytesToWrite = job.getLong("test.randomwrite.total_bytes",
            numMapsPerHost * numBytesToWritePerMap * cluster.getTaskTrackers());
    int numMaps = (int) (totalBytesToWrite / numBytesToWritePerMap);
    if (numMaps == 0 && totalBytesToWrite > 0) {
        numMaps = 1;
        job.setLong("test.randomwrite.bytes_per_map", totalBytesToWrite);
    }

    job.setNumMapTasks(numMaps);
    System.out.println("Running " + numMaps + " maps.");

    // reducer NONE
    job.setNumReduceTasks(0);

    Date startTime = new Date();
    System.out.println("Job started: " + startTime);
    JobClient.runJob(job);
    Date endTime = new Date();
    System.out.println("Job ended: " + endTime);
    System.out.println("The job took " + (endTime.getTime() - startTime.getTime()) / 1000 + " seconds.");

    return 0;
}

From source file:com.benchmark.mapred.SleepJob.java

License:Apache License

public JobConf setupJobConf(int numMapper, int numReducer, long mapSleepTime, int mapSleepCount,
        long reduceSleepTime, int reduceSleepCount) {
    JobConf job = new JobConf(getConf(), SleepJob.class);
    job.setNumMapTasks(numMapper);/*  ww  w. j  av  a  2  s  . c o  m*/
    job.setNumReduceTasks(numReducer);
    job.setMapperClass(SleepJob.class);
    job.setMapOutputKeyClass(IntWritable.class);
    job.setMapOutputValueClass(NullWritable.class);
    job.setReducerClass(SleepJob.class);
    job.setOutputFormat(NullOutputFormat.class);
    job.setInputFormat(SleepInputFormat.class);
    job.setPartitionerClass(SleepJob.class);
    job.setSpeculativeExecution(false);
    job.setJobName("Sleep job");
    FileInputFormat.addInputPath(job, new Path("ignored"));
    job.setLong("sleep.job.map.sleep.time", mapSleepTime);
    job.setLong("sleep.job.reduce.sleep.time", reduceSleepTime);
    job.setInt("sleep.job.map.sleep.count", mapSleepCount);
    job.setInt("sleep.job.reduce.sleep.count", reduceSleepCount);
    return job;
}

From source file:com.benchmark.mapred.Sort.java

License:Apache License

/**
 * The main driver for sort program./*from   w w  w .j  av  a 2  s.  com*/
 * Invoke this method to submit the map/reduce job.
 * @throws IOException When there is communication problems with the 
 *                     job tracker.
 */
public int run(String[] args) throws Exception {

    JobConf jobConf = new JobConf(getConf(), Sort.class);
    jobConf.setJobName("sorter");

    jobConf.setMapperClass(IdentityMapper.class);
    jobConf.setReducerClass(IdentityReducer.class);

    JobClient client = new JobClient(jobConf);
    ClusterStatus cluster = client.getClusterStatus();
    int num_reduces = (int) (cluster.getMaxReduceTasks() * 0.9);
    String sort_reduces = jobConf.get("test.sort.reduces_per_host");
    if (sort_reduces != null) {
        num_reduces = cluster.getTaskTrackers() * Integer.parseInt(sort_reduces);
    }
    Class<? extends InputFormat> inputFormatClass = SequenceFileInputFormat.class;
    Class<? extends OutputFormat> outputFormatClass = SequenceFileOutputFormat.class;
    Class<? extends WritableComparable> outputKeyClass = BytesWritable.class;
    Class<? extends Writable> outputValueClass = BytesWritable.class;
    List<String> otherArgs = new ArrayList<String>();
    InputSampler.Sampler<K, V> sampler = null;
    for (int i = 0; i < args.length; ++i) {
        try {
            if ("-m".equals(args[i])) {
                jobConf.setNumMapTasks(Integer.parseInt(args[++i]));
            } else if ("-r".equals(args[i])) {
                num_reduces = Integer.parseInt(args[++i]);
            } else if ("-inFormat".equals(args[i])) {
                inputFormatClass = Class.forName(args[++i]).asSubclass(InputFormat.class);
            } else if ("-outFormat".equals(args[i])) {
                outputFormatClass = Class.forName(args[++i]).asSubclass(OutputFormat.class);
            } else if ("-outKey".equals(args[i])) {
                outputKeyClass = Class.forName(args[++i]).asSubclass(WritableComparable.class);
            } else if ("-outValue".equals(args[i])) {
                outputValueClass = Class.forName(args[++i]).asSubclass(Writable.class);
            } else if ("-totalOrder".equals(args[i])) {
                double pcnt = Double.parseDouble(args[++i]);
                int numSamples = Integer.parseInt(args[++i]);
                int maxSplits = Integer.parseInt(args[++i]);
                if (0 >= maxSplits)
                    maxSplits = Integer.MAX_VALUE;
                sampler = new InputSampler.RandomSampler<K, V>(pcnt, numSamples, maxSplits);
            } else {
                otherArgs.add(args[i]);
            }
        } catch (NumberFormatException except) {
            System.out.println("ERROR: Integer expected instead of " + args[i]);
            return printUsage();
        } catch (ArrayIndexOutOfBoundsException except) {
            System.out.println("ERROR: Required parameter missing from " + args[i - 1]);
            return printUsage(); // exits
        }
    }

    // Set user-supplied (possibly default) job configs
    jobConf.setNumReduceTasks(num_reduces);

    jobConf.setInputFormat(inputFormatClass);
    jobConf.setOutputFormat(outputFormatClass);

    jobConf.setOutputKeyClass(outputKeyClass);
    jobConf.setOutputValueClass(outputValueClass);

    // Make sure there are exactly 2 parameters left.
    if (otherArgs.size() != 2) {
        System.out.println("ERROR: Wrong number of parameters: " + otherArgs.size() + " instead of 2.");
        return printUsage();
    }
    FileInputFormat.setInputPaths(jobConf, otherArgs.get(0));
    FileOutputFormat.setOutputPath(jobConf, new Path(otherArgs.get(1)));

    if (sampler != null) {
        System.out.println("Sampling input to effect total-order sort...");
        jobConf.setPartitionerClass(TotalOrderPartitioner.class);
        Path inputDir = FileInputFormat.getInputPaths(jobConf)[0];
        inputDir = inputDir.makeQualified(inputDir.getFileSystem(jobConf));
        Path partitionFile = new Path(inputDir, "_sortPartitioning");
        TotalOrderPartitioner.setPartitionFile(jobConf, partitionFile);
        InputSampler.<K, V>writePartitionFile(jobConf, sampler);
        URI partitionUri = new URI(partitionFile.toString() + "#" + "_sortPartitioning");
        DistributedCache.addCacheFile(partitionUri, jobConf);
        DistributedCache.createSymlink(jobConf);
    }

    System.out.println("Running on " + cluster.getTaskTrackers() + " nodes to sort from "
            + FileInputFormat.getInputPaths(jobConf)[0] + " into " + FileOutputFormat.getOutputPath(jobConf)
            + " with " + num_reduces + " reduces.");
    Date startTime = new Date();
    System.out.println("Job started: " + startTime);
    jobResult = JobClient.runJob(jobConf);
    Date end_time = new Date();
    System.out.println("Job ended: " + end_time);
    System.out.println("The job took " + (end_time.getTime() - startTime.getTime()) / 1000 + " seconds.");
    return 0;
}

From source file:com.benchmark.mapred.terasort.TeraValidate.java

License:Apache License

public int run(String[] args) throws Exception {
    JobConf job = (JobConf) getConf();
    TeraInputFormat.setInputPaths(job, new Path(args[0]));
    FileOutputFormat.setOutputPath(job, new Path(args[1]));
    job.setJobName("TeraValidate");
    job.setJarByClass(TeraValidate.class);
    job.setMapperClass(ValidateMapper.class);
    job.setReducerClass(ValidateReducer.class);
    job.setOutputKeyClass(Text.class);
    job.setOutputValueClass(Text.class);
    // force a single reducer
    job.setNumReduceTasks(1);//from w  w  w .j  a  v a 2  s  .  c om
    // force a single split 
    job.setLong("mapred.min.split.size", Long.MAX_VALUE);
    job.setInputFormat(TeraInputFormat.class);
    JobClient.runJob(job);
    return 0;
}

From source file:com.bigdata.diane.MiniTestDFSIO.java

License:Apache License

@SuppressWarnings("deprecation")
private static void runIOTest(Class<? extends Mapper<Text, LongWritable, Text, Text>> mapperClass,
        Path outputDir, Configuration fsConfig) throws IOException {
    JobConf job = new JobConf(fsConfig, MiniTestDFSIO.class);

    FileInputFormat.setInputPaths(job, CONTROL_DIR);
    job.setInputFormat(SequenceFileInputFormat.class);

    job.setMapperClass(mapperClass);//from  ww  w. jav a 2s. c o  m
    job.setReducerClass(AccumulatingReducer.class);

    FileOutputFormat.setOutputPath(job, outputDir);
    job.setOutputKeyClass(Text.class);
    job.setOutputValueClass(Text.class);
    job.setNumReduceTasks(1);
    JobClient.runJob(job);
}

From source file:com.chriscx.mapred.Driver.java

public int run(String[] args) throws Exception {
    JobConf conf = new JobConf(getConf(), Driver.class);
    conf.setJobName("wordcount");

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

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

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

    List<String> other_args = new ArrayList<String>();
    for (int i = 0; i < args.length; ++i) {
        if ("-skip".equals(args[i])) {
            DistributedCache.addCacheFile(new Path(args[++i]).toUri(), conf);
            conf.setBoolean("wordcount.skip.patterns", true);
        } else {/*from   www  .  j a  va  2 s. c o m*/
            other_args.add(args[i]);
        }
    }

    FileInputFormat.setInputPaths(conf, new Path(other_args.get(0)));
    FileOutputFormat.setOutputPath(conf, new Path(other_args.get(1)));

    JobClient.runJob(conf);
    return 0;
}

From source file:com.chriscx.matching.Driver.java

public int run(String[] args) throws Exception {
    JobConf conf = new JobConf(getConf(), com.chriscx.mapred.Driver.class);
    conf.setJobName("Matching");

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

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

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

    List<String> other_args = new ArrayList<String>();
    for (int i = 0; i < args.length; ++i) {
        if ("-skip".equals(args[i])) {
            DistributedCache.addCacheFile(new Path(args[++i]).toUri(), conf);
            conf.setBoolean("wordcount.skip.patterns", true);
        } else {//from   www .ja  v a 2 s  .c o m
            other_args.add(args[i]);
        }
    }

    FileInputFormat.setInputPaths(conf, new Path(other_args.get(0)));
    FileOutputFormat.setOutputPath(conf, new Path(other_args.get(1)));

    JobClient.runJob(conf);
    return 0;
}

From source file:com.cloudera.avro.AvroWordCount.java

License:Apache License

public int run(String[] args) throws Exception {
    if (args.length != 2) {
        System.err.println("Usage: AvroWordCount <input path> <output path>");
        return -1;
    }//from   www.  ja va2s  .  c o  m

    JobConf conf = new JobConf(AvroWordCount.class);
    conf.setJobName("wordcount");

    // We call setOutputSchema first so we can override the configuration
    // parameters it sets
    AvroJob.setOutputSchema(conf, Pair.getPairSchema(Schema.create(Type.STRING), Schema.create(Type.INT)));

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

    conf.setInputFormat(TextInputFormat.class);

    conf.setMapOutputKeyClass(Text.class);
    conf.setMapOutputValueClass(IntWritable.class);
    conf.setOutputKeyComparatorClass(Text.Comparator.class);

    FileInputFormat.setInputPaths(conf, new Path(args[0]));
    FileOutputFormat.setOutputPath(conf, new Path(args[1]));

    JobClient.runJob(conf);
    return 0;
}

From source file:com.cloudera.hbase.OldWordCount.java

License:Open Source License

public static void main(String[] args) throws Exception {
    JobConf conf = new JobConf(WordCount.class);
    String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();

    if (otherArgs.length != 2) {
        System.err.println("Usage: wordcount <in> <out>");
        System.exit(2);/*from  w  ww . j  a v a 2  s .c om*/
    }
    conf.setJobName("word count");

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

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

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

    FileInputFormat.setInputPaths(conf, new Path(otherArgs[0]));
    FileOutputFormat.setOutputPath(conf, new Path(otherArgs[1]));
    JobClient.runJob(conf);
    return;
}