How load library in jar file?

I have a native method for a C program i wrote. I want to package the whole thing into a jar executable. However, when I do that, it can no longer find the library. It always throws an ubnsatisfied link exception. I tried adding ".;jarfile.jar" to the library path with System.setProperty but it still couldn't find it. Does anyone know how I can do this?

Apparently there's no standardized way of doing this. So I just read the file in as a resourcestream (from the jar file), figured out what folder I was in and created the dll file there.