com.ifeng.vdn.videolog.sort.SortGroupResultPreprocessor.java Source code

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Here is the source code for com.ifeng.vdn.videolog.sort.SortGroupResultPreprocessor.java

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/*
 * Copyright 2010-2011 the original author or authors.
 *
 * Licensed 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.ifeng.vdn.videolog.sort;

import java.io.File;
import java.io.IOException;

import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileUtil;
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.mapreduce.lib.output.SequenceFileOutputFormat;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.Mapper;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @version 0.1
 *
 * @author Hefei Li
 *
 * @since May 16, 2015
 */
public class SortGroupResultPreprocessor extends Configured implements Tool {
    private static final Logger log = LoggerFactory.getLogger(SortGroupResultPreprocessor.class);

    static class SortGroupResultMapper extends Mapper<LongWritable, Text, IntWritable, Text> {

        @Override
        protected void map(LongWritable key, Text value,
                Mapper<LongWritable, Text, IntWritable, Text>.Context context)
                throws IOException, InterruptedException {

            String[] items = value.toString().split("\t");

            context.write(new IntWritable(Integer.parseInt(items[1])), new Text(items[0]));

            log.info("key = {}, value = {}", key, value);
        }

    }

    @Override
    public int run(String[] args) throws Exception {
        if (args.length != 2) {
            System.err.printf("Usage: %s [generic options] <input> <output>\n", getClass().getSimpleName());
            ToolRunner.printGenericCommandUsage(System.err);
            return -1;
        }

        Job job = Job.getInstance(getConf());
        job.setMapperClass(SortGroupResultMapper.class);
        job.setNumReduceTasks(0);

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

        FileInputFormat.addInputPath(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));

        // Sort data by total number:
        job.setOutputFormatClass(SequenceFileOutputFormat.class);

        return job.waitForCompletion(true) ? 0 : 1;
    }

    public static void main(String[] args) throws Exception {
        if (args == null || args.length != 2) {
            args = new String[] { "src/test/resources/input/sort/count-result.txt",
                    "src/test/resources/output/sort-countresult" };
        }

        FileUtil.fullyDelete(new File(args[1]));

        int exitCode = ToolRunner.run(new SortGroupResultPreprocessor(), args);

        System.exit(exitCode);

    }

}