Usage of Serial Com Port communication

[calvinlyp]

Hi all,

currently i am trying to use a java app to read from my usb to serial port on my PC.

i research and found that Windows COM ports are not directly supported by Sun anymore. thus there is another package called rxtx.

JAVA: Serial Port access with javax.comm or rxtx on Windows, Linux etc.
i tried the above link with my app, however it return me portId=null;

from the link below:
New Windows Java Serial Com Port driver with proper handling of Timeouts
it stated that the usb to serial maybe a problem when using the rxtx package, and this winjcom maybe a good substitute.

however, is there any expertises can share their advice on how to use this winjcom.

thanks in advance.
any help will be greatly appreaciated.