The Java Communications API

This chapter covers the Java Communications API, a standard extension that can send data to and receive data from RS-232 serial ports and IEEE 1284-parallel ports. This allows Java programs to talk to essentially any device connected to a serial or parallel port, like a printer, a scanner, a modem, a tape backup unit, and so on. The Communications API operates at a very low level. It only understands how to send and receive bytes to these ports. It does not understand anything about what these bytes mean. Doing useful work generally requires not only understanding the Java Communications API (which is actually quite simple) but also the protocols spoken by the devices connected to the ports (which can be almost arbitrarily complex).