Basicly there are two main ways. One is to pass the info in the HTML Parm as mentioned, the other way is to have the Applet pull a specific web page ( call a perl script, static file, or HTML ) that returns the informaiton you want. You can also encode the informaiton in the perl and decode it in the applet so it is not directly readable by someone monitoring the connection or going directly to the webpage.

I do the second option for a little game I programmed. The Java applet that displayes the users status calls a perl CGI script on the server which returns the status then the applet POSTs the responce to a perl script which writes back to the db on the sever.

Java can always write and read from the server it originates from, but it can only read and write locally if it is signed and the user accepts it.

IF you are interested let me know and I can send you a link to an example. I don't want to post links to WIP which will live in PM archives.