Originally posted by ngo thanhson:
I thought that I we only need the .class file inorder to call third-party class.
If you want to extract the class, you need to make sure you put the file in the correct place (WEB-INF/classes/{full package structure}/class).
Also, that class may or may not have dependencies of it's own.
There is a good chance that those dependencies are not going to be listed in the author's documentation if they are all included in the jar file.
IOW: Unless you have a real good reason to do so, don't unpack the jar file.