使用MapReduce统计每一个用户的使用总流量

有上图这样的文件，需要统计每个用户使用的上行总流量，下行总流量和总流量

第一步：创建一个用户类如下：

package com.zut.flow;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;

import org.apache.hadoop.io.Writable;

public class Flow implements Writable{
	private String tel;
	private long up;
	private long dw;
	private long total;

	public Flow() {
		super();
	}
	
	public Flow(long up, long dw, long total) {
		super();
		this.up = up;
		this.dw = dw;
		this.total = total;
	}
	public Flow(String tel, long up, long dw, long total) {
		super();
		this.tel = tel;
		this.up = up;
		this.dw = dw;
		this.total = total;
	}
	
	

	public String getTel() {
		return tel;
	}

	public void setTel(String tel) {
		this.tel = tel;
	}

	public long getUp() {
		return up;
	}

	public void setUp(long up) {
		this.up = up;
	}

	p