com.uc.qiujw.WordCount.java Source code

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Here is the source code for com.uc.qiujw.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 com.uc.qiujw;

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

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.GenericOptionsParser;

public class WordCount implements Run {
    public int run(String[] args) {
        try {
            WordCount.main(args);
        } catch (Exception e) {
            e.printStackTrace();
            return 1;
        }
        return 0;
    }

    public String getKey() {
        return "wordcount";
    }

    private final static String mapSleepKey = "com.uc.qiujw.map.sleep";
    private final static String reduceSleepKey = "com.uc.qiujw.reduce.sleep";

    public static class TokenizerMapper extends Mapper<Object, Text, Text, IntWritable> {

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

        @Override
        public void setup(Context context) throws IOException, InterruptedException {
            printMem();
            int mapSleep = context.getConfiguration().getInt(mapSleepKey, 10);
            System.out.print(mapSleep);
            Thread.sleep(mapSleep * 1000);
        }

        @Override
        public void map(Object key, Text value, Context context) throws IOException, InterruptedException {
            StringTokenizer itr = new StringTokenizer(value.toString());
            while (itr.hasMoreTokens()) {
                word.set(itr.nextToken());
                context.write(word, one);
            }
        }

        @Override
        public void cleanup(Context context) throws IOException, InterruptedException {
            printMem();
            int mapSleep = context.getConfiguration().getInt(mapSleepKey, 10);
            System.out.print(mapSleep);
            Thread.sleep(mapSleep * 1000);
        }

    }

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

        @Override
        protected void setup(Context context) throws IOException, InterruptedException {
            printMem();
            int reduceSleep = context.getConfiguration().getInt(reduceSleepKey, 1);
            System.out.print(reduceSleep);
            Thread.sleep(reduceSleep * 1000);
        }

        public void reduce(Text key, Iterable<IntWritable> values, Context context)
                throws IOException, InterruptedException {
            int sum = 0;
            for (IntWritable val : values) {
                sum += val.get();
            }
            result.set(sum);
            context.write(key, result);
        }

        @Override
        public void cleanup(Context context) throws IOException, InterruptedException {
            printMem();
            int reduceSleep = context.getConfiguration().getInt(reduceSleepKey, 1);
            System.out.print(reduceSleep);
            Thread.sleep(reduceSleep * 1000);
        }

    }

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

        System.err.println("Usage: wordcount  <in> <out> <map_sleep> <reduce_sleep>");

        Job job = Job.getInstance(conf, "word count");
        job.setJarByClass(WordCount.class);
        job.setMapperClass(TokenizerMapper.class);
        job.setCombinerClass(IntSumReducer.class);
        job.setReducerClass(IntSumReducer.class);
        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(IntWritable.class);
        String[] in = otherArgs[0].split(",");
        String out = otherArgs[1];
        for (String inStr : in) {
            FileInputFormat.addInputPath(job, new Path(inStr));
        }
        FileOutputFormat.setOutputPath(job, new Path(out));
        int mapSleep = 1, reduceSleep = 1;
        if (otherArgs.length > 2) {
            mapSleep = Integer.valueOf(otherArgs[2]);
        }
        if (otherArgs.length > 3) {
            reduceSleep = Integer.valueOf(otherArgs[3]);
        }
        conf.set(mapSleepKey, Integer.toString(mapSleep));
        conf.set(reduceSleepKey, Integer.toString(reduceSleep));
        FileSystem fs = FileSystem.get(conf);
        Path outPath = new Path(out);
        if (fs.exists(outPath)) {
            fs.delete(outPath, true);
        }
        System.exit(job.waitForCompletion(true) ? 0 : 1);
    }

    public static void printMem() {
        Runtime r = Runtime.getRuntime();
        long total = r.totalMemory();
        long free = r.freeMemory();

        System.out.println("total:" + total + " free:" + free);
    }

}