Solved: Eclipse javadoc hover gone

The problem:

I don’t see the usual javadoc hover in Eclipse IDE.

Cause:

I used the same workspace on different computers, so some file permissions got messed up. This caused an exception in the hover-rendering internals.

Solution:

Regain ownership over whole workspace: (of course while Eclipse is closed)

user@host:/path/to/workspace$ sudo chown -R ${USER}: .

Additional conclusions:

• It’s useful to look for errors in ~/.xsession-errors, that receives the standard error of X windows.
• from man find: -nouser No user corresponds to file's numeric user ID.
• It’s useful to have a place where I can write down these findings ;) I’m pretty sure I once already solved this problem, but then forgot about it.