Question

尝试运行一个Hadoop Map Reduce代码，但低于错误。不知道为什么......

hadoop jar BWC11.jar WordCountDriver “/家/培训/ training_material /数据/莎士比亚/喜剧片” “/家/培训/ training_material /数据/莎士比亚/ AWL” 警告：不推荐使用$ HADOOP_HOME。
Exception in thread "main" java.lang.NoClassDefFoundError: WordCountDriver (wrong name:
COM /菲利克斯/ hadoop的/训练/ WordCountDriver） at java.lang.ClassLoader.defineClass1（Native Method） at java.lang.ClassLoader.defineClass（ClassLoader.java:791） at java.security.SecureClassLoader.defineClass（SecureClassLoader.java:142） at java.net.URLClassLoader.defineClass（URLClassLoader.java:449）在java.net.URLClassLoader.access $ 100（URLClassLoader.java:71）在java.net.URLClassLoader $ 1.run（URLClassLoader.java:361）在java.net.URLClassLoader $ 1.run（URLClassLoader.java:355） at java.security.AccessController.doPrivileged（Native Method）在java.net.URLClassLoader.findClass（URLClassLoader.java:354） at java.lang.ClassLoader.loadClass（ClassLoader.java:423） at sun.misc.Launcher $ AppClassLoader.loadClass（Launcher.java:308） at java.lang.ClassLoader.loadClass（ClassLoader.java:410） at java.lang.ClassLoader.loadClass（ClassLoader.java:356） at java.lang.Class.forName0（Native Method） at java.lang.Class.forName（Class.java:264）在org.apache.hadoop.util.RunJar.main（RunJar.java:149） [training @ localhost BasicWordCount] $

有人可以帮我解决这个问题吗？

驱动程序代码：

package com.felix.hadoop.training;

import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IntWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.Job;
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.util.Tool;
import org.apache.hadoop.util.ToolRunner;


public class WordCountDriver extends Configured implements Tool{

    public static void main(String[] args) throws Exception
    {
        ToolRunner.run(new WordCountDriver(),args);
    }

    @Override
    public int run(String[] args) throws Exception {

        Job job = new Job(getConf(),"Basic Word Count Job");
        job.setJarByClass(WordCountDriver.class);

        job.setMapperClass(WordCountMapper.class);
        job.setReducerClass(WordCountReducer.class);

        job.setInputFormatClass(TextInputFormat.class);

        job.setMapOutputKeyClass(Text.class);
        job.setMapOutputValueClass(IntWritable.class);

        job.setOutputKeyClass(Text.class);
        job.setOutputValueClass(IntWritable.class);

        job.setNumReduceTasks(1);

        FileInputFormat.addInputPath(job, new Path(args[0]));
        FileOutputFormat.setOutputPath(job, new Path(args[1]));

        job.waitForCompletion(true);



        return 0;
    }


}

映射器代码：

package com.felix.hadoop.training;

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;
/**
 * 
 * @author training
 * Class : WordCountMapper
 *
 */

public class WordCountMapper extends Mapper<LongWritable, Text, Text, IntWritable>{
    /**
     * Optimization: Instead of creating the variables in the 
     */

    @Override
    public void map(LongWritable inputKey,Text inputVal,Context context) throws IOException,InterruptedException
    {
        String line = inputVal.toString();
        String[] splits = line.trim().split("\\W+");
        for(String outputKey:splits)
        {
            context.write(new Text(outputKey), new IntWritable(1));

        }


    }

}

减速机代码：

package com.felix.hadoop.training;
import java.io.IOException;

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


public class WordCountReducer extends Reducer<Text,IntWritable,Text, IntWritable>{

    @Override
    public void reduce(Text key,Iterable<IntWritable> listOfValues,Context context) throws IOException,InterruptedException
    {
        int sum=0;
        for(IntWritable val:listOfValues)
        {
            sum = sum + val.get();
        }
        context.write(key,new IntWritable(sum));


    }

}

不确定我为什么会收到这个错误.. 我试图将class path复制的类文件添加到.jar文件所在的位置等...但无济于事。

Answer 1

添加包名称＆＃34; com.felix.hadoop.training＆＃34;在"WordCountDriver"之前。

在Hadoop实践中遇到错误

1 个答案: