org.apache.accumulo.examples.simple.mapreduce.WordCount.java Source code

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Here is the source code for org.apache.accumulo.examples.simple.mapreduce.WordCount.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.accumulo.examples.simple.mapreduce;

import java.io.IOException;

import org.apache.accumulo.core.client.mapreduce.AccumuloOutputFormat;
import org.apache.accumulo.core.data.Mutation;
import org.apache.accumulo.core.data.Value;
import org.apache.accumulo.core.util.CachedConfiguration;
import org.apache.commons.cli.BasicParser;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.HelpFormatter;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.Options;
import org.apache.commons.cli.Parser;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

/**
 * A simple map reduce job that inserts word counts into accumulo. See the README for instructions on how to run this.
 * 
 */
public class WordCount extends Configured implements Tool {
    private static Options opts;
    private static Option passwordOpt;
    private static Option usernameOpt;
    private static String USAGE = "wordCount <instance name> <zoo keepers> <input dir> <output table>";

    static {
        usernameOpt = new Option("u", "username", true, "username");
        passwordOpt = new Option("p", "password", true, "password");

        opts = new Options();

        opts.addOption(usernameOpt);
        opts.addOption(passwordOpt);
    }

    public static class MapClass extends Mapper<LongWritable, Text, Text, Mutation> {
        @Override
        public void map(LongWritable key, Text value, Context output) throws IOException {
            String[] words = value.toString().split("\\s+");

            for (String word : words) {

                Mutation mutation = new Mutation(new Text(word));
                mutation.put(new Text("count"), new Text("20080906"), new Value("1".getBytes()));

                try {
                    output.write(null, mutation);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    public int run(String[] unprocessed_args) throws Exception {
        Parser p = new BasicParser();

        CommandLine cl = p.parse(opts, unprocessed_args);
        String[] args = cl.getArgs();

        String username = cl.getOptionValue(usernameOpt.getOpt(), "root");
        String password = cl.getOptionValue(passwordOpt.getOpt(), "secret");

        if (args.length != 4) {
            System.out.println("ERROR: Wrong number of parameters: " + args.length + " instead of 4.");
            return printUsage();
        }

        Job job = new Job(getConf(), WordCount.class.getName());
        job.setJarByClass(this.getClass());

        job.setInputFormatClass(TextInputFormat.class);
        TextInputFormat.setInputPaths(job, new Path(args[2]));

        job.setMapperClass(MapClass.class);

        job.setNumReduceTasks(0);

        job.setOutputFormatClass(AccumuloOutputFormat.class);
        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(Mutation.class);
        AccumuloOutputFormat.setOutputInfo(job.getConfiguration(), username, password.getBytes(), true, args[3]);
        AccumuloOutputFormat.setZooKeeperInstance(job.getConfiguration(), args[0], args[1]);
        job.waitForCompletion(true);
        return 0;
    }

    private int printUsage() {
        HelpFormatter hf = new HelpFormatter();
        hf.printHelp(USAGE, opts);
        return 0;
    }

    public static void main(String[] args) throws Exception {
        int res = ToolRunner.run(CachedConfiguration.getInstance(), new WordCount(), args);
        System.exit(res);
    }
}