mapreduce案例_电信用户平均停留时间

package com.wll.dianxin;
import org.apache.hadoop.conf.Configuration;
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.Reducer;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;

import java.io.IOException;

class TimeMapper extends Mapper<LongWritable, Text,Text,LongWritable>{
    @Override
    protected void map(LongWritable key, Text value, Mapper<LongWritable, Text, Text, LongWritable>.Context context) throws IOException, InterruptedException {
        String line = value.toString();
        if (line.endsWith("03")){
            String[] split = line.split("\t");
            context.write(new Text(split[0]+"-"+split[2]),new LongWritable(Integer.parseInt(split[4])));
        }
    }
}

class TimeReducer extends Reducer<Text,LongWritable,Text,LongWritable>{
    @Override
    protected void reduce(Text key, Iterable<LongWritable> values, Reducer<Text, LongWritable, Text, LongWritable>.Context context) throws IOException, InterruptedException {
        long sum=0L;
        long count=0L;
        for (LongWritable value : values) {
            sum+=value.get();
            count++;
        }
        context.write(key,new LongWritable(sum/count));

    }
}

public class TimeDemo{
    public static void main(String[] args) throws Exception{
        Configuration conf = new Configuration();
        conf.set("fs.defaultFS", "hdfs://master:9000");

        Job job = Job.getInstance(conf);

        job.setJarByClass(TimeDemo.class);

        job.setJobName("用户平均停留时长统计案例");

        job.setMapperClass(TimeMapper.class);

        job.setReducerClass(TimeReducer.class);

        job.setMapOutputKeyClass(Text.class);

        job.setMapOutputValueClass(LongWritable.class);

        job.setOutputKeyClass(Text.class);

        job.setOutputValueClass(LongWritable.class);

        FileInputFormat.setInputPaths(job,new Path(args[0]));

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

        boolean b = job.waitForCompletion(true);
        if (b){
            System.out.println("用户平均停留时长案例mapreduce实现执行成功！>_-");
        }else {
            System.out.println("用户平均停留时长案例mapreduce实现执行失败");
        }


    }
}

结果