Java 在hadoop中运行程序时出错？

我在wordcount的hadoop 2.7中的程序在运行时在终端上给出错误，即使它在eclipse中没有显示任何错误

hadoop jar WordCount.jar WordCount用户/amandeph/file.txt wordcountoutput

错误如下所示：-

Exception in thread "main" java.lang.ClassNotFoundException: WordCount
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Class.java:274)
at org.apache.hadoop.util.RunJar.run(RunJar.java:214)
at org.apache.hadoop.util.RunJar.main(RunJar.java:136)

我的字数计算程序是-

package hadoop_first;

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.mapred.FileInputFormat;
import org.apache.hadoop.mapred.FileOutputFormat;
import org.apache.hadoop.mapred.JobClient;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.util.Tool;
import org.apache.hadoop.util.ToolRunner;

public class WordCount extends Configured implements Tool{

    @Override
    public int run(String[] args) throws Exception {
        if(args.length<2){
            System.out.println("Give directory properly");
            return -1;
        }
        JobConf conf = new JobConf(WordCount.class);
        conf.setJarByClass(WordCount.class);
        FileInputFormat.setInputPaths(conf,new Path(args[0]));
        FileOutputFormat.setOutputPath(conf,new Path(args[1]));
        conf.setMapperClass(WordCountMapper.class);
        conf.setReducerClass(WordReducer.class);
        conf.setMapOutputKeyClass(Text.class);
        conf.setMapOutputValueClass(IntWritable.class);

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

        JobClient.runJob(conf);
        return 0;
    }
    public static void main(String args[]){
        try{
            int exitCode=ToolRunner.run(new WordCount(),args);
            System.exit(exitCode);
        }
        catch(Exception e){
            System.out.println("Error");
        }
    }
} 

先打包hadoop\u；
导入org.apache.hadoop.conf.Configured；
导入org.apache.hadoop.fs.Path；
导入org.apache.hadoop.io.IntWritable；
导入org.apache.hadoop.io.Text；
导入org.apache.hadoop.mapred.FileInputFormat；
导入org.apache.hadoop.mapred.FileOutputFormat；
导入org.apache.hadoop.mapred.JobClient；
导入org.apache.hadoop.mapred.JobConf；
导入org.apache.hadoop.util.Tool；
导入org.apache.hadoop.util.ToolRunner；
公共类WordCount扩展配置的实现工具{
@凌驾
公共int运行（字符串[]args）引发异常{
if（args.length通过在终端键入的命令中添加包名解决了该问题

hadoop jar WordCount.jar hadoop_first.WordCount file.txt wordcountoutput