MapReduce中的字数统计

Question

我已经看到线程已经解决了这个错误，但不知何故，解决方案对我没有帮助。 我正在运行以下代码：

public class WordCount
{
    public static class MyMapper extends Mapper<LongWritable,Text,Text,IntWritable>
    {
        final static IntWritable one=new IntWritable(1);
        Text word=new Text();

        public void map(LongWritable key,Text Value,Context context) throws IOException,InterruptedException
        {
            String line=Value.toString();
            StringTokenizer itr=new StringTokenizer(line);
            while (itr.hasMoreTokens())
            {
                word.set(itr.nextToken());
                context.write(word, one);
            }
        }

    }

    public static class MyReducer extends Reducer<Text,IntWritable,Text,IntWritable>{

        public void reduce(Text Key,Iterable<IntWritable> Values,Context context) throws IOException,InterruptedException
        {
            int sum=0;
            for (IntWritable value:Values)
            {
                sum=sum+value.get();
            }
            context.write(Key, new IntWritable(sum));}



        public static void main(String[] args) throws IOException, InterruptedException, ClassNotFoundException
        {

            //Job job=new Job();
            Configuration conf=new Configuration();
            Job job=new Job(conf,"Word Count");

            job.setJarByClass(WordCount.class);
            job.setMapperClass(MyMapper.class);
            job.setReducerClass(MyReducer.class);
            job.setOutputKeyClass(Text.class);
            job.setOutputValueClass(IntWritable.class);
            FileInputFormat.addInputPath(job, new Path(args[0]));
            FileOutputFormat.setOutputPath(job,new Path(args[1]));
            System.exit(job.waitForCompletion(true) ? 0 : 1);
        }
    }
}

它具有正确格式的主要方法。 当我试图运行它时，它会给我以下错误。

 **hadoop jar MyTesting-0.0.1-SNAPSHOT.jar MyPackage.WordCount <Input> <Output>**
Exception in thread "main" java.lang.NoSuchMethodException: MyPackage.WordCount.main([Ljava.lang.String;)
        at java.lang.Class.getMethod(Class.java:1670)
        at org.apache.hadoop.util.RunJar.run(RunJar.java:215)
        at org.apache.hadoop.util.RunJar.main(RunJar.java:136)