Although the dev's said they provide java integration after they could support this feature, it would be very good to provide the libraries and integration in this early beta stage.
The possibilities of the java integration in a3 are endless, and on the other hand there's for sure alot of bugs, problems and feature requests to this topic. If the devs provide this feature only in very late beta stages, or even worse in the release version, this could be very bad for all of us: Security problems, untested api, etc...
Sideeffect, modders could test these possibilities and plan mods using java.
But that's too much work now!
I don't say the api should be comprehensive. A simple api for sidechat would be enough for a sneak peak.