Eclipse was working as good as anything on 14.04. I did a clean install of 16.04 and installed Eclipse. But it runs a Java program only once after which it just hangs during subsequent attempts before I remove and reinstall it. I have tried many things, since in the beginning I needed CDT as well. Right now, I just want to remove everything related to eclipse and do a fresh install (remove all the configs and dependencies). Please note that I used Eclipse installer to install Eclipse and the eclipse icon image is also not appearing (the default ubuntu ? is appearing).
I had something the same with 16.04 and Eclipse Mars. I thought it had frozen but in fact it was running very, very slowly. The problem is the version of GTK+ 3, shipped with 16.04. Fortunately the solution is very easy. Open a terminal and then type
export SWT_GTK3=0, then start Eclipse from the terminal. If that works, then a more persistent fix is to put the 2 lines below, as they appear in your
before the line:
The bug is filed with Ubuntu at bug 1552764