java - How to set up multiple source folders within a single Eclipse project?

Question

I have several somewhat separate programs, that conceptually can fit into a single project. However, I'm having trouble telling Eclipse to make several folders inside a project folder.

A simple form of the structure would be:

/UberProject
/UberProject/ProgramA/
/UberProject/ProgramA/com/pkg/NiftyReader.java
/UberProject/ProgramB/
/UberProject/ProgramB/com/pkg/NiftyWriter.java

That is, ProgramA and ProgramB are both projects (in fact, they're currently existing Java projects), which conceptually fit into UberProject.

I don't think I'm supposed to make UberProject be a Java project; it's not a classpath, for instance. ProgramA and ProgramB do seem like they should be Java projects (they might use different build dependencies as well), but I see no way in Eclipse 3.3 to create two folders under UberProject that are intended to contain Java code. I thought about adding a .project file to each of the two sub-projects, but I'm not sure that's appropriate, either. Eclipse help isn't being helpful, and I didn't see anything on SO about this specific problem.

Just to be clear: assume as given the necessity of the existence of UberProject. UberProject can be a Java project, or not; it doesn't matter. (Incidentally, it does contain other folders that do not contain Java code.)

Answer 1

There are probably several ways to do this:

1) UberProject is your JavaProject. Right click ProgramA -> Build Path -> Use as source folder. Right click ProgramB -> Build Path -> Use as source folder. Both ProgramA and ProgramB will do incremental builds to the same directory.

2) Two java projects (ProgramA and ProgramB). You can use UberProject as your eclipse workspace which would be easiest or you can use an outside workspace and import ProgramA and ProgramB as external projects.

There are probably other ways as well (maven multi-module project). Your choice probably depends on whether you have cyclic dependencies between projects. It should be relatively easy to try both 1 and 2 and see what works best for you.