Is it possible to intercept all incoming requests for processing before forwarding them to the normal handler in the container?
I am looking for an Orbix/OrbixWeb style "filter", or a Visigenic style "interceptor".
Short answer - NO. If I recall, there is work in JCP process to modify RMI to support such things, but I have seen no details.
Of course, you can generate the stubs using the -keep (do I remember that correctly) method. This will keep the source code. After this you can modify the source code if you want. I've done this once, but it isn't really a clean way of doing things. But if you are really stuck, it's possible...
For EJB no. The new servlet spec includes filters though which would do that. That only gives you what you need for HTTP though.