haoop 错误记录

源代码：

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

import org.apache.hadoop.fs.Path;
import org.apache.hadoop.conf.*;
import org.apache.hadoop.io.*;
import org.apache.hadoop.mapred.*;
//import org.apache.hadoop.mapred.JobConf;


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

public void map(LongWritable key,Text value,OutputCollector<Text,IntWritable> output,Reporter reporter) throws IOException{
String line=value.toString();
StringTokenizer tokenizer=new StringTokenizer(line);
while(tokenizer.hasMoreTokens()){
word.set(tokenizer.nextToken());
output.collect(word, one);
}
}
}

public static class Reduce extends MapReduceBase implements Reducer<Text,IntWritable,Text,IntWritable>{

public void reduce (Text key,Iterator<IntWritable> values,OutputCollector<Text,IntWritable> output,Reporter reporter) throws IOException{
try{
int sum=0;
while(values.hasNext()){
sum+=values.next().get();
}
output.collect(key, new IntWritable(sum));
}
catch(IOException e){
System.out.println("nkenxknxknecxkn");
}

}
}

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

JobConf conf=new JobConf();
conf.setJobName("WordCount");

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

conf.setMapperClass(Map.class);
conf.setReducerClass(Reduce.class);

conf.setInputFormat(TextInputFormat.class);
conf.setOutputFormat(TextOutputFormat.class);

FileInputFormat.setInputPaths(conf, new Path(args[0]));
FileOutputFormat.setOutputPath(conf, new Path(args[1]));

JobClient.runJob(conf);
}
}

eclipse 错误显示：

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory

    at org.apache.hadoop.conf.Configuration.<clinit>(Configuration.java:143)
    at WordCount.main(WordCount.java:45)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
    ... 2 more