cn.lhfei.hadoop.ch04.MaxTemperatureWithCompression.java Source code

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Here is the source code for cn.lhfei.hadoop.ch04.MaxTemperatureWithCompression.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 cn.lhfei.hadoop.ch04;

import java.io.IOException;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.compress.GzipCodec;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

import cn.lhfei.hadoop.ch02.MaxTemperatureMapper;
import cn.lhfei.hadoop.ch02.MaxTemperatureReducer;

/**
 * use case: % hadoop MaxTemperatureWithCompression input/ncdc/sample.txt.gz output
 * @version 0.1
 *
 * @author Hefei Li
 *
 * @since Oct 28, 2014
 */

public class MaxTemperatureWithCompression {

    public static void main(String[] args) {
        if (args.length != 2) {
            System.err.println("Usage: MaxTemperatureWithCompression <input path> " + "<output path>");
            System.exit(-1);
        }

        try {
            Job job = new Job();
            job.setJarByClass(MaxTemperatureWithCompression.class);

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

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

            FileOutputFormat.setCompressOutput(job, true);
            FileOutputFormat.setOutputCompressorClass(job, GzipCodec.class);

            job.setMapperClass(MaxTemperatureMapper.class);
            job.setCombinerClass(MaxTemperatureReducer.class);
            job.setReducerClass(MaxTemperatureReducer.class);

            System.exit(job.waitForCompletion(true) ? 0 : 1);

        } catch (IOException e) {
            e.printStackTrace();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

    }

}