Exception in thread "main " java.lang.NoClassDefFoundError:ReadID3

import java.io.*;public class ReadID3{
public static void main(String[] arguments){
try{
File song =new File(arguments[0]);
FileInputStream file =new FileInputStream(song);
int size=(int)song.length();
file.skip(size-128);
byte[] last128 =new byte[128];
file.read(last128);
String id3=new String(last128);
String tag=id3.substring(0,3);
if(tag.equals("TAG")){
System.out.println("Title: "+id3.substring(3,32));
System.out.println("Arist: "+id3.substring(33,62));
System.out.println("Album: "+id3.substring(63,91));
System.out.println("Year: "+id3.substring(92,97));
}else
System.out.println(arguments[0]+ " does not contain ID3 info.");
file.close();

}catch(Exception e){
System.out.println("Error--"+e.toString());
}
}
}运行：java ReadID3 Dengerously_in_lover_3.mp3
（Dengerously_in_lover_3.mp3是本地磁盘的音乐文件）
出现错误：Exception   in   thread     "main "   java.lang.NoClassDefFoundError:ReadID3正确结果应该是：
Title:Dengerously_in_lover_3.mp3
Arist: ......
Album:  ......
Year: ......