WritableComparable分区内排序案例

此案例是在 WritableComparable全排序案例 基础上完成

FlowBean
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public class FlowBean implements WritableComparable<FlowBean> {
    ······
        @Override
    public int compareTo(FlowBean o) {
        if(this.sumFlow!=o.getSumFlow()) {
            return this.sumFlow > o.getSumFlow() ? -1 : 1;
        }else {
            return 0;
        }
    }
    ······
}
CustomPartition
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package flowsum2;

import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Partitioner;

public class CustomPartition extends Partitioner<Text,FlowBean> {
    @Override
    public int getPartition(Text text, FlowBean flowBean, int i) {
        String line=text.toString();
        if(line.startsWith("13")){
            return 0;
        }else if(line.startsWith("14")){
            return 1;
        }else if(line.startsWith("15")){
            return 2;
        }else if(line.startsWith("17")){
            return 3;
        }else{
            return 4;
        }
    }
}

FlowCountDriver
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job.setPartitionerClass(CustomPartition.class);//自定义分区
job.setNumReduceTasks(5);//分区个数