Java network programming

You may remember me from a couple of my tutorials on java programming. Well I've always wanted to get into the networking aspect of java programming. I tried to look at the Java API specification page and it was too hard to just look at the page and do it. So I thought I'd start by learning from other programs that people have written. So I turned to google and found this site: http://www.cs.utexas.edu/users/chris...s/sockets.html
It has a lot of usefull stuff, and I tried out the Knock knock client server thing. I got it to work and it is really neat how you can just write a a server and client like that. Here is the page for the knock knock thing:
http://java.sun.com/docs/books/tutor...entServer.html
I just thought I'd share this with you all because networking is cool and I've always wanted to build my own server. For now I've just copied one, but I hope to build my own in the near future.
Hope you all gain some knowledge from these links.