How do I totally remove all Eclipse and Java from my installation ?

[linux guy]

I have been trying to install Eclipse on my computer for 2 days, on and
off.   It worked once, after some fiddling, but its messed up now.

How do I totally remove all Eclipse and Java elements from my computer
so that I can start fresh.  (And don't tell me to reinstall !)

For Eclipse, I have been removing all the eclipse packages with yum and
then removing /usr/lib/eclipse and ~/.eclipse.  Is this enough ?

What do I do for the Java components ?

Thanks