sample code for chat application

I've just started learning servlets. Which is best for developing chat application - using servlets or RMI. Also is there any sample code available on the web for a chat application.
Thanks .

check this site, i hope u can get wat u want, n i can get wat i want
http://javaboutique.internet.com/servlets/servlets.html

meena
according to me developing chat application using rmi is the best .

meena , why you want oter's code ? you don't want to create anything of your own. You learn servlets properly & rmi properly. then , go for developing any application.
make small application of chat server. then , you can add funcationality to it. You create your own novel chat server , with sound support , video support ( api's from java ).
on net you will get many sample chat server code. But , will you be having any satisfaction of doing good job. you learn theam , but create your own thing. I hope this is helpful.