用java编写话费统计的MR程序，计算每个电话号码的总流量，包括上行流量，下行流量的代码

好的，这里提供一份Java编写话费统计的MR程序示例代码：

import java.io.IOException;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.*;
 
public class PhoneFlowCount {
 
    public static class Map extends MapReduceBase implements Mapper<Text, Text, Text, FlowBean> {
 
        private Text phoneNum = new Text();
        private FlowBean flowBean = new FlowBean();
 
        public void map(Text key, Text value, OutputCollector<Text, FlowBean> output, Reporter reporter)
                throws IOException {
            String line = value.toString();
            String[] fields = line.split("\t");
            phoneNum.set(fields[0]);
            long upFlow = Long.parseLong(fields[1]);
            long downFlow = Long.parseLong(fields[2]);
            flowBean.set(upFlow, downFlow);
            output.collect(phoneNum, flowBean);
        }
    }
 
    public static class Reduce extends MapReduceBase implements Reducer<Text, FlowBean, Text, FlowBean> {
 
        private FlowBean result = new FlowBean();
 
        public void reduce(Text key, Iterator<FlowBean> values, OutputCollector<Text, FlowBean> output,
                           Reporter reporter) throws IOException {
            long upFlow = 0;
            long downFlow = 0;
            while (values.hasNext()) {
                FlowBean bean = values.next();
                upFlow += bean.getUpFlow();
                downFlow += bean.getDownFlow();
            }
            result.set(upFlow, downFlow);
            output.collect(key, result);
        }
    }
 
    public static void main(String[] args) throws Exception {
 
        JobConf conf = new JobConf(PhoneFlowCount.class);
        conf.setJobName("phone_flow_count");
 
        conf.setMapperClass(Map.class);
        conf.setReducerClass(Reduce.class);
 
        conf.setOutputKeyClass(Text.class);
        conf.setOutputValueClass(FlowBean.class);
 
        FileInputFormat.setInputPaths(conf, new Path(args[0]));
        FileOutputFormat.setOutputPath(conf, new Path(args[1]));
 
        JobClient.runJob(conf);
    }
}

在上述代码中，FlowBean是一个自定义的数据类型，用于存储每个手机号码的上下行流量数据。在Map阶段中，我们将输入的每行数据按照制表符进行拆分，然后将手机号码作为键，上下行流量作为值进行输出；在Reduce阶段中，我们对每个手机号码的上下行流量进行累加，最终得到每个手机号码的总流量，并将其作为值进行输出。