Update: java server now returns "true" or "false" based on an internal file, but doesn't actually take an ID (it's just a value I typed into the code,5006 at the moment). Setting up a server was easier than I expected, took under an hour.
The code is there to edit the file as well, but nothing runs it yet (that's the last step before I move to the Blockland side). I'm going to be unable to work on the project for a while, though.
edit: bumpable-ification magic!