RMI skeleton and stubs

Hi,
I'm studying RMI and have been reading a book. In the book they speak about having to generate a stub and a skeleton class.
However, I also did the exercise on the site below and it seems it worked fine, without having to create a stub or skeleton. http://java.sun.com/docs/books/tutorial/rmi/overview.html
Can anyone explain please???
Thanks

in fact, i don't understand the paragraph below on the site:
"Later, in JDK 1.2, the skeletons were incorporated into the server itself so that there are no separate entities as skeletons. In other words, the skeletons's functionality was incorporated into the server itself. So, the scenario became like this:
Client<--->stub<--->[NETWORK]<--->Server_with_skeleton_functionality"
how does it works then????
i understand the concept with stubs and skeletons well, but now that skeletons are not needed anymore, i'm a bit lost....
you can just indicate a class to extend "remote", and then compile it with javac ?
from then on the remote class file can remotely be called???
right???

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