Exception in thread "main" java.lang.ClassNotFoundException: com.mysql.jdbc.Driver

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 sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)

at java.lang.ClassLoader.loadClass(ClassLoader.java:358)

at java.lang.Class.forName0(Native Method)

at java.lang.Class.forName(Class.java:190)

at jdbc_chuan.Jdbc_util.main(Jdbc_util.java:19)

我想問一下那個驅動是不是zip格式的，還是要解壓成文件夾再放進來呢