Why can't eclipse resolve class in same package?

Question

I hit F5 ~1000 times and restarted eclipse (also with -clean), deleted /bin, but nothing helps. Manually importing DoodleClient does not help. DoodleClient exists and is perfect

Answer 1

None of the things above worked.

However I could fix it like this:

1. Installed a new Eclipse Version
2. Opened a new workspace
3. Cloned my Maven projects from my Git repo into the new workspace
4. Imported them in Eclipse as Maven Projects

Result: Eclipse finds classes again.