Of course leJOS supports Bluetooth on the EV3 (via the Linux Bluez and debus interface), how else do you think it handles all of the stuff to search and pair with devices etc? But you should not be using the low level dbus package to do those things, instead you should be using the higher level classes like LocalBTDevice and RemoteBTDevice. Take a look at the menu code to see how to use it.
The classes you have linked to are versions of the "standard Java" Bluetooth control mechanism, but I don't think that has ever really worked and does not really provide all of the functionality required. The dbus and other leJOS Bluetooth classes provide the mechanism to discover, pair and control the Bluetooth stack. Once that has all been setup you can just use the standard Java network API to actually create connections etc. It can also be used to talk to an NXT or other device. There are classes in the remote part of the class library to allow an EV3 to talk via Bluetooth to an NXT. See:https://lejosnews.wordpress.com/2014/04 ... nntroller/
I'm not sure what it is you want to "test", perhaps you could explain further.
Also rather than posting topics with a title like "Doubt about" perhaps you could use "Questions about", "Doubt about" implies that there is some sort of problem, but most of these topics just seem to be asking for information about things.