If you are working on a legacy system, I can provide tips on: Finding the libraries Troubleshooting the "No serial ports found" error
It is not part of the standard JDK, requiring manual installation of comm.jar and platform-specific native libraries ( .dll or .so files).
Uses a Java event model to detect changes in signal lines (e.g., carrier detect). Review & Status (As of 2026) Package Javax Comm
It can be notoriously difficult to configure, often requiring precise placement of javax.comm.properties . It has known limitations with 64-bit Windows and is not truly cross-platform without bundling separate native libraries for each target system.
While it was once a stable and flexible solution for Java-to-hardware communication, javax.comm should be avoided for new projects . It is extremely difficult to set up on modern systems, and superior, actively maintained libraries are readily available. If you are working on a legacy system,
(like jSerialComm) if you are starting a new project. What is your current goal with javax.comm ? Opening up new ports to Java with javax.comm - InfoWorld
The de facto standard replacement for many years was RXTX (e.g., org.rxtx:rxtxcomm ), but it is also considered old. Modern Java serial communication is typically handled via modern, maintained libraries like jSerialComm or jSSC (Java Simple Serial Connector). It has known limitations with 64-bit Windows and
The package, often referred to as the Java Communications API or JavaComm, is a legacy API developed by Sun Microsystems to provide Java applications with low-level, asynchronous access to serial ( ) and parallel ports. Overview & Purpose