我创建了一个mapreduce程序来获取世界指标数据，以显示我要分析的特定指标的结果(i、 e.二氧化碳排放）。数据以长线排列，包括国家、代码、指标、第一年排放量、第二年排放量等。在我的Map绘制程序中，我试图只保留我想要的数据（首先，如果有具体指标，只保留该行），然后保留国家和所有排放水平（以字符串数组形式）。
我的整个程序都在运行，但我注意到它正在接收Map输入记录，但没有Map输出记录或reduce输入/输出记录。
我一直想弄清楚我的逻辑哪里出错了，但我被难住了。任何意见都将不胜感激。
我的代码如下：
---Map器--

package org.myorg;

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.mapreduce.Mapper;

public class CO2Mapper extends Mapper <LongWritable, Text, Text, IntWritable>
{
    public void map(LongWritable key, Text value, Context context) throws IOException, InterruptedException
    {
        String delims = ",";
        String splitString = value.toString();

        String[] tokens = splitString.split(delims);

        int tokenCount = tokens.length;
        String country = tokens[1]; 
        String indicator = tokens[3];
        int levels;

        if(indicator.equals("EN.ATM.CO2E.KT"))
        {   
            for (int j = 4; j < tokenCount; j++)
            {
                levels = Integer.parseInt(tokens[j]);
                context.write(new Text(country), new IntWritable(levels));
            }
        }
    } 
}

----减速机---

package org.myorg;

import java.io.IOException;

import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Reducer;

public class CO2Reducer extends Reducer<Text, IntWritable, Text, IntWritable>
{
    @Override
    public void reduce(Text key, Iterable<IntWritable> values, Context context) throws IOException, InterruptedException
    {
        int maxValue = Integer.MIN_VALUE;
        int minValue = Integer.MAX_VALUE;
        for(IntWritable val : values)
        {
            maxValue = Math.max(maxValue, val.get());
            minValue = Math.min(minValue, val.get());
        }

        context.write(key, new IntWritable(maxValue));
        context.write(key, new IntWritable(minValue));
    }
}

---主要---

package org.myorg;

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.conf.Configuration;

import org.apache.hadoop.mapreduce.*;
import org.apache.hadoop.mapreduce.lib.input.FileInputFormat;
import org.apache.hadoop.mapreduce.lib.input.TextInputFormat;
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat;
import org.apache.hadoop.mapreduce.lib.output.TextOutputFormat;
//import org.apache.hadoop.mapreduce.lib.input.KeyValueTextInputFormat;

public class CO2Levels 
{

    public static void main(String[] args) throws Exception  
    {    
        //with mapreduce

        Configuration conf = new Configuration();
        Job job = new Job(conf, "co2Levels");

        //Job job = new Job();

        job.setJarByClass(CO2Levels.class);
        //job.setJobName("co2Levels");
        job.setMapperClass(CO2Mapper.class);
        job.setReducerClass(CO2Reducer.class);
        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(IntWritable.class);
        job.setOutputFormatClass(TextOutputFormat.class);
        job.setInputFormatClass(TextInputFormat.class);
        //job.setInputFormatClass(KeyValueTextInputFormat.class);
        FileInputFormat.addInputPath(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));
        System.exit(job.waitForCompletion(true) ? 0 : 1);

    }
}