代码

import org.apache.commons.lang.ObjectUtils;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.conf.Configured;import org.apache.hadoop.fs.Path;import org.apache.hadoop.io.NullWritable;import org.apache.hadoop.io.Text;import org.apache.hadoop.mapreduce.Job;import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;import org.apache.hadoop.util.Tool;import org.apache.hadoop.util.ToolRunner;/** * Created with IntelliJ IDEA. * User: @别慌 * Date: 2019-06-16 * Time: 0:44 * Description: */public class PartitionerMain extends Configured implements Tool {    public int run(String[] args) throws Exception {        //job类，组装MR        Job job=Job.getInstance(super.getConf(),PartitionerMain.class.getSimpleName());        //打包运行        job.setJarByClass(PartitionerMain.class);        //第一步：读取文件，解析kv对        job.setInputFormatClass(TextInputFormat.class);        TextInputFormat.addInputPath(job,new Path(args[0]));        //自定义map逻辑        job.setMapperClass(partitionMap.class);        job.setMapOutputKeyClass(Text.class);        job.setMapOutputValueClass(NullWritable.class);        //第三部  分区         job.setPartitionerClass(partitionerOwn.class);        //自定义reduce逻辑        job.setReducerClass(partitionReduce.class);        job.setOutputKeyClass(Text.class);        job.setOutputValueClass(NullWritable.class);        job.setNumReduceTasks(2);        //设置输出类        job.setOutputFormatClass(TextOutputFormat.class);        //输出路径不写死，通过参数传进来        TextOutputFormat.setOutputPath(job,new Path(args[1]));        //提交任务        boolean b =job.waitForCompletion(true);        return b?0:1;    }    public static void main(String args[]) throws Exception {        int run= ToolRunner.run(new Configuration(),new PartitionerMain(),args);        System.exit(run);    }}import org.apache.hadoop.io.NullWritable;import org.apache.hadoop.io.Text;import org.apache.hadoop.mapreduce.Partitioner;/** * Created with IntelliJ IDEA. * User: @别慌 * Date: 2019-06-16 * Time: 0:56 * Description: */public class partitionerOwn extends Partitioner
      
        {    public int getPartition(Text text, NullWritable nullWritable, int i) {        String[] spilt=text.toString().split("\t");        String gameResult=spilt[5];        if (null != gameResult && ""!=gameResult){            if (Integer.parseInt(gameResult)>15){                return 0;            }else {                return 1;            }        }        return 0;    }}import org.apache.hadoop.io.LongWritable;import org.apache.hadoop.io.NullWritable;import org.apache.hadoop.io.Text;import org.apache.hadoop.mapreduce.Mapper;import java.io.IOException;/** * Created with IntelliJ IDEA. * User: @别慌 * Date: 2019-06-16 * Time: 0:47 * Description: */public class partitionMap  extends Mapper
       
          {    protected  void  map(LongWritable key, Text value, Context context) throws IOException, InterruptedException {        context.write(value, NullWritable.get());    }}import org.apache.hadoop.io.NullWritable;import org.apache.hadoop.io.Text;import org.apache.hadoop.mapreduce.Reducer;import java.io.IOException;/** * Created with IntelliJ IDEA. * User: @别慌 * Date: 2019-06-16 * Time: 1:14 * Description: */public class partitionReduce extends Reducer
        
          {    protected  void reduce(Text key,Iterable
         
           values,Context context) throws IOException, InterruptedException {        context.write(key,NullWritable.get());    }}
         
        
       
      

pom.xml

      
          
       
        4.0.0
           
       
        com.ali
           
       
        hdfs
           
       
        1.0-SNAPSHOT
           
               
                    
         
          org.apache.hadoop
                     
         
          hadoop-common
                     
         
          2.9.0
                 
                
                    
         
          org.apache.hadoop
                     
         
          hadoop-hdfs
                     
         
          2.9.0
                 
                
                
                    
         
          org.apache.hadoop
                     
         
          hadoop-mapreduce-client-core
                     
         
          2.9.0
                 
            
       
      

java项目架构

• PartitionerMain
• partitionerOwn
• partitionMap
• partitionReduce

hadoop   jar  mouse.jar   PartitionerMain    /partition   /outtest

                     jar包            main函数            hdfs上的目标文件      hdfs的输出文件（不能事先存在）

源文件（partition）

1    0    1    2017-07-31 23:10:12    834232    6    sadasaa2    9    6    2019-06-76 78:97:12    687907    45    dsdskd