org.apache.mahout.avro.text.mapred.AvroDocumentsWordCount.java Source code

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Here is the source code for org.apache.mahout.avro.text.mapred.AvroDocumentsWordCount.java

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/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.mahout.avro.text.mapred;

import java.io.IOException;
import java.util.Iterator;
import java.util.StringTokenizer;

import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.serializer.WritableSerialization;
import org.apache.hadoop.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
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.Reducer;
import org.apache.hadoop.mapred.Reporter;
import org.apache.hadoop.mapred.RunningJob;
import org.apache.hadoop.mapred.TextOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.apache.log4j.Logger;
import org.apache.mahout.avro.document.AvroDocument;
import org.apache.mahout.avro.document.AvroDocumentReader;
import org.apache.mahout.avro.document.AvroFieldReader;
import org.apache.mahout.hadoop.io.serializer.avro.AvroGenericSerialization;
import org.apache.mahout.hadoop.io.serializer.avro.AvroReflectSerialization;
import org.apache.mahout.hadoop.io.serializer.avro.AvroSpecificSerialization;
import org.apache.mahout.hadoop.mapred.AvroInputFormat;

/** Generates word counts for documents stored in avro document format */
public class AvroDocumentsWordCount extends Configured implements Tool {

    private static final Logger log = Logger.getLogger(AvroDocumentsWordCount.class);

    public static class TokenizerMapper extends MapReduceBase
            implements Mapper<AvroDocument, LongWritable, Text, IntWritable> {

        private final static IntWritable one = new IntWritable(1);
        private Text word = new Text();

        private final AvroDocumentReader dr = new AvroDocumentReader();
        private final AvroFieldReader fr = new AvroFieldReader();

        public void map(AvroDocument key, LongWritable value, OutputCollector<Text, IntWritable> collector,
                Reporter reporter) throws IOException {
            dr.wrap(key);
            fr.wrap(dr.getField("content"));

            StringTokenizer itr = new StringTokenizer(fr.getOriginalText());
            while (itr.hasMoreTokens()) {
                word.set(itr.nextToken());
                collector.collect(word, one);
            }
        }
    }

    public static class IntSumReducer extends MapReduceBase
            implements Reducer<Text, IntWritable, Text, IntWritable> {
        private IntWritable result = new IntWritable();

        public void reduce(Text key, Iterator<IntWritable> values, OutputCollector<Text, IntWritable> collector,
                Reporter reporter

        ) throws IOException {
            int sum = 0;
            while (values.hasNext()) {
                sum += values.next().get();
            }
            result.set(sum);
            collector.collect(key, result);
        }
    }

    @Override
    public int run(String[] args) throws Exception {
        JobConf conf = new JobConf();
        if (args.length != 2) {
            System.err.println("Usage: wordcount <in> <out>");
            return 0;
        }

        conf.setStrings("io.serializations",
                new String[] { WritableSerialization.class.getName(), AvroSpecificSerialization.class.getName(),
                        AvroReflectSerialization.class.getName(), AvroGenericSerialization.class.getName() });

        conf.setJarByClass(AvroDocumentsWordCount.class);
        conf.setMapperClass(TokenizerMapper.class);
        conf.setCombinerClass(IntSumReducer.class);
        conf.setReducerClass(IntSumReducer.class);
        conf.setOutputKeyClass(Text.class);
        conf.setOutputValueClass(IntWritable.class);

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

        Path input = new Path(args[0]);
        Path output = new Path(args[1]);

        FileSystem fs = FileSystem.get(conf);
        fs.delete(output, true);

        AvroInputFormat.setAvroInputClass(conf, AvroDocument.class);
        FileInputFormat.addInputPath(conf, input);
        FileOutputFormat.setOutputPath(conf, output);

        RunningJob job = JobClient.runJob(conf);
        job.waitForCompletion();

        return job.isSuccessful() ? 1 : 0;
    }

    public static void main(String[] args) throws Exception {
        ToolRunner.run(new AvroDocumentsWordCount(), args);
    }

}