package com.cn.sort;import java.io.IOException;import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Mapper;public class SortMapper extends Mapper<Object, Text, IntWritable, IntWritable> {String line = null;@Overrideprotected void map(Object key, Text value, Context context)throws IOException, InterruptedException {line = value.toString();int lineValue = Integer.parseInt(line);context.write(new IntWritable(lineValue), new IntWritable(1));}
}

package com.cn.sort;import java.io.IOException;import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.mapreduce.Reducer;public class SortReduce extends Reducer<IntWritable, IntWritable, IntWritable, IntWritable>{IntWritable lineNum = new IntWritable(1);@Overrideprotected void reduce(IntWritable key, Iterable<IntWritable> values,Context context)throws IOException, InterruptedException {for(IntWritable value : values){context.write(lineNum, key);lineNum = new IntWritable(lineNum.get()+1);}}
}

package com.cn.sort;import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.mapreduce.Job;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.util.GenericOptionsParser;/*** 数据排序* @author root**/
public class DataSort {public static void main(String[] args) throws Exception {Configuration conf = new Configuration();String[] otherArgs = new GenericOptionsParser(conf, args).getRemainingArgs();if (otherArgs.length != 2) {System.err.println("Usage: DataSort  ");System.exit(2);}Job job = new Job(conf, "Data Sort");  job.setJarByClass(DataSort.class);//设置输入输出文件目录FileInputFormat.addInputPath(job, new Path(otherArgs[0]));FileOutputFormat.setOutputPath(job, new Path(otherArgs[1]));//设置mapper和reduce处理逻辑类job.setMapperClass(SortMapper.class);job.setReducerClass(SortReduce.class);//设置输出key-value类型job.setOutputKeyClass(IntWritable.class);job.setOutputValueClass(IntWritable.class);//提交作业并等待它完成System.exit(job.waitForCompletion(true) ? 0 : 1);}}