Is it possible to test your java code w/o compiling all server?

Is it possible to test your java code w/o compiling all server?

Testing a code means if the change is on core then you have to change the jar file nothing else expect if you add more files

example configs htmls.

But i need just to compile my code not all server is this possible?

You know you can add and remove code during debugging? It's very useful to know how to do it.

http://wiki.eclipse.org/FAQ_What_is_hot_code_replace%3F