Dear Friend, the only way I know to do that in
java is trough "native method". You must implement the methods you create in java, those that you don't want to be uncompiled, in another compiled native language like c or c++, to make a DLL. Use the javah tool to make a header file to interface the java code and the DLL. But have a question. Why do you want protect your code from uncompiling?
You should be benign with other programmers that doesn't know how to do make some things.
Well, good look in your project