.dll already loaded in another classloader?

Question

I have a webapp running under Tomcat 3.2.1 that needs to make JNI calls in order to access data and methods in legacy C++ code. A servlet is loaded on startup of the webapp

Answer 1

Copy the DLLs to temporary files in a temporary directory before loading them. Delete the files when you are done. This way you can ensure that the same DLL is not loaded twice.