Java EE (Java Enterprise Edition) General Discussion

Hello

did not know which forum to choose but this one seems most appropriate.

My question is:
Where can I find more information about commonly used project structures? I'm not able to find much articles or other info on this on the web?

Some web applications have there all there source code, web content, libraries, ... in one project.
I've also seen a project which has several eclipse projects: one for configuration, one for UI, one for domain, one for common stuff, one for services layer, one for test, ... sometimes up to ten of which each one has his own packaging, ... .

Are there guidelines are standards or so described in literature?
What is your approach to structure your code?

Thanks.
Tim