我一直在研究hadoop-2.4.0，为了运行基于java的hadoop示例，我在类路径上放置了所需的lib

export HADOOP_HOME= /root/hadoop-binaries/hadoop-2.4.0    
CLASSPATH=/root/hadoop-binaries/hadoop-2.4.0/conf
CLASSPATH=$CLASSPATH:$HADOOP_HOME/*:$HADOOP_HOME/lib/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../hadoop-mapreduce/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../hadoop-mapreduce/lib/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../hadoop-yarn/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../hadoop-yarn/lib/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../hadoop-hdfs/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../hadoop-hdfs/lib/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../common/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../common/lib/*
CLASSPATH=$CLASSPATH:$HADOOP_HOME/../tools/lib/*

我已经将所有需要的hadoop库从hadoop\u主页添加到类路径中。
但是，当我尝试运行示例javac-cp$classpath helloworld.java时
它提醒我一个错误

HelloWorld.java:4: error: package org.apache.hadoop.conf does not exist
import org.apache.hadoop.conf.Configuration;                                 ^
1 error

我不知道在哪里可以找到org.apache.hadoop.conf的lib。