Where I could find javx.comm package ??

I gone on java.sun.com but I found this package only under windows and solaris.

Where I could find this package please.

are you trying to do this under linux?
I am not sure about this since i've never done it myself but with linux i believe u can just open the specified port under /dev/ as a File and just write and read from it.

For example if you are working with a modem the code is something like

File outputFile = new File("/dev/modem");
..and then RandomAccessFile...yada yada ya