do they work? should we even display them?
They work, sort of. We should display them, but note that they are
both experimental.
We have used JIGS in production systems in the tomcat servlet engine for over a
decade.
That's quite limited use (we use it to call objc code from java), but it works
reliably.
I've also made extensive use of it to call java code from objc (in order to use
a jdbc database client library from objc code).
It does have a few disadvantages:
If you have bad objc code and cause a crash in the objc world, of course it
kills the process, which is pretty bad if that process is the servlet engine
dealing with a large web site.
When you have objc code that leaks memory (or just uses a lot) its invisible to
the java garbage collector and you can carelessly run the process out of memory.
When those problems occur in the ObjC world, it's very hard to debug them
inside a massively multi-threaded Java process.
None of those are really issues with JIGS though ... as a bridging technology
it works well.