This is a java Library to connect a system that runs grbl (https://github.com/grbl/grbl). The connections works with a single byte stream interface for generic and easy binding to the Serial Port, a Usb virtual Serial Port, Bluetooth Device, ...
In my case, I use it to run a panoramic head with Arduino and grbl as firmware and i use this connector to write a android app to control the panohead via Bluetooth.