Well your receipt printer should function similar to a typical printer plugged into the computer.
Your first step should be confirming this. Get your hands on the printer, plug it into your computer, install any needed drivers, and see if you can print to it from an application.
If so, then all you need to look into is printing in Java. Check out the official documentation here:
http://docs.oracle.com/javase/tutori...ing/index.html.
Otherwise, you'll need to contact the printer's manufacturer as they're probably exists some sort of SDK for use in your application.