[java] [Java] Using a custom-made controller

Hello dear folks, I'm trying to find out how to build a custom controller, connect it to a computer, and use Java to read input from the controller. As I've understood there are basically three options: 1. Use the gameport and let the controller be a gamepad with a certain number of axes and buttons. However, I'm a bit concerned with the Java connectivity, and the fact that gameports are often not found on small PC's. 2. Use the serial port and write a custom interface. There is a 'Java Communications API' that should allow to do this, but it appears to work only under Linux. I'd like to have something cross-platform in this case. 3. Use the USB port. However, I can't find many articles on this topic. There are two libraries I found: 'jUSB' (OSS for Linux) and another - of which the site seems to be down - for Windows. But here too, I would like to have something cross platform. So, would there be any cross-platform way to connect a custom-built controller to a computer and use it with Java? Thanks.