I've looked extensively on Google for JNI tutorials and documentation,
but I can't seem to figure this out;  I can't be the first one to have
wanted to do this, or maybe I am just misunderstanding the way JNI
works.

I have a dll from another company.  It is a total black box and I do
not have access to the source code at all.  I have great documentation
on the API functions themselves so that is not a problem.

I am trying to call functions on the dll from Java, but all the things
I have read include running javah on the class file (which I can
successfully do), but it doesn't seem to help because I don't have
access to the source code, so I can't really use the header file.

Writing a wrapper library to implement the functions from the dll to
specifically work with Java (including jni.h, etc) is not at all
feasible because there are hundreds and hundreds of functions, and I
don't have enough time to write a library for them all.

Any help anyone can give would be most appreciated!