[GUIDE REQUEST] Problem with Run (cmd)

Hey Guys NInjachickwen here :p
I have a problem and i need help
when i open cmd i get this issue

Code:

Exception in thread "main" java.lang.NoClassDefFoundError: client
Caused by: java.lang.ClassNotFoundException: client
        at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: client.  Program will exit.
Press any key to continue . . .

Can Any One Help?

~NinjaChicken