Calling jar classes from java executable

[SteM]

Hi all,
I have a java application in the form of exe file (Windows).
From this application i need to load an external jar and execute it.
Using methods Class.forName(), getMethod() amd invoke() I made some steps but I have some problems.
I'm able to instanciate the main class in the jar but when the code instances another class (in the jar) I receive a java.lang.NoSuchMethodError exception.

In general :
how can i load all the classes contained into the jar archive?
which classes defined in the second app i can invoke from the first one?
which classes defined in the first app i can invoke from the second one?
if I should have the same class in both app, what happens?

Thanks a lot !!

[sandeepkk2005]

If you want to invoke it as a separate application then use

Runtime.getRuntime.exec("java -jar yourJarFileName.jar");

if u want to use the functions(or methods) then put the jar file in classpath, import it & create the object and use the methods.