Java OBD Adapter - My Library on Github
Quite recently, I wrote a library supporting connections to cars equipped with OBD sockets (generally speaking, all models made after 2003). The library is available on my github profile - https://github.com/devesion/java-obd-adapter . It supports many AT and OBD commands and is fully functional - I mean, you can read major sensor values and make use of them in your android app or any kind of java component.
I’ve tested it on my Raspberry Pi as well as Intel Edison and my laptop. In a physical layer I’ve been using bluetooth dongles (Vgate and some cheap noname), wifi dongle (Vgate) and wired serial connection. Everything worked well with dedicated Diamex simulator as well as my old 2006 Jetta (thanks to this library I was able to detect some problem with my Massive Air Flow).
Feel free to use this library and contribute by forking, opening issues, making pull requests etc.