我有密码

import java.io.IOException; 
 import java.util.*;

 import org.apache.hadoop.io.IntWritable;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.mapred.*;

 public class SalesCountryReducer extends MapReduceBase implements Reducer<Text, IntWritable, Text, IntWritable> {
public void reduce(Text t_key, Iterator<IntWritable> values, OutputCollector<Text,IntWritable> output, Reporter reporter) throws IOException {
    Text key = t_key;
    int frequencyForCountry = 0;
    while (values.hasNext()) {
        // replace type of value with the actual type of our value
        IntWritable value = (IntWritable) values.next();
        frequencyForCountry += value.get();

        }
        output.collect(key, new IntWritable(frequencyForCountry));
    }
}

和

import java.io.IOException;

import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.LongWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapred.*;

public class SalesMapper extends MapReduceBase implements Mapper<LongWritable, Text, Text, IntWritable> {
    private final static IntWritable one = new IntWritable(1);

    public void map(LongWritable key, Text value, OutputCollector<Text, IntWritable> output, Reporter reporter) throws IOException {

        String valueString = value.toString();
        String[] SingleCountryData = valueString.split(",");
        output.collect(new Text(SingleCountryData[7]), one);
    }
}

在这段代码中，我计算了每个国家执行操作的次数。我需要这样做，每个国家的总收入将显示。如果你能帮助我，这将是巨大的。因为我都不知道怎么做。
csv文件