COM port access is made through the javax.comm api.
The latest version of the comm api does not support Windows, so if you are on that platform your options are listed on our Java IO FAQ.
java com api for windows can be downloaded from ...
No, sorry, downloading native code from an anonymous file sharing site is a huge security risk. That's not what we want to encourage people to do. The javax.com implementation can be downloaded from http://java.sun.com/products/javacomm/