The ParameterCountMismatchError exception alerts you to the fact that the called function consumed (popped off the stack) more or fewer parameters than was passed by J/Direct. This error normally indicates that the parameters in the Java method declaration do not match up with the parameters expected by the DLL function.
If the function pops off no arguments, it is assumed to be using the cdecl calling convention and an exception is not thrown, even if the Java method declares a non-zero number of arguments.
CAUTION You should not attempt to catch and deal with the ParameterCountMismatchError exception. This exception was designed to assist developers in catching errors during the development stage. For performance reasons, parameter count checking is performed only when the application is running under a Java debugger. It is also important to note that J/Direct performs this check after the function call has been completed. Because this exception indicates that one or more invalid parameters might have been passed to the function call, it cannot be guaranteed that the process can recover.