Inspired by the recent addition of module groups in Irida, my XDoclet2 sandbox project now has 86 modules, including all of the XDoclet plugins, all the Jelly tags, Picocontainer and all the Nanocontainer modules, and a few other miscellaneous things.

Learning other projects with IDEA is a breeze, expecially when the source is imported as a module. One of the issues I've had in the past was whether to treat the source as a library with attached sources or as a module with a dependency. But I've come to the conclusion that modules are the only way to go. You can easily change source in the other projects and use the fantastic JUnit Runner that is built into IDEA to run tests.

Of course, a lot of this assumes that you are working with projects in Maven. This is because the work for setting up these modules is enabled by using the "idea:multiproject" goal in maven to generate all of the .iml files. Then, I just copy the lines in the generate .ipr file over to my master project, make module groups for all the modules, and I am flying.

If you are going to try this at home, be sure to get the latest version of the multiproject plugin from CVS. Brett just committed some changes the other day that will make it work with a small change to the module format.