I just finished a rough month making the site Appletmaker.
It lets you post source like other sites but it is also an ONLINE IDE!
Complete with online compiling and hosting for your applets.
It has a step by step tutorial for new users and modding an existing applet.
I have an object based game layer that is supported by the site that allows people to share classes and simply add them to their projects and see them work.
The site also supports stand alone applets and all Java platforms.
Email me email@example.com
if you want help learning java games.
These Java game forums are perfect forums and will be linked from Appletmaker!
Lets make games! Don't know how? I will teach you.