I use eclipse Indigo, subclipse 1.10.x and javaNL. Whenever I try to refresh my project in eclipse, it gets stuck at Reverting Resources 0% and Computing Update Requirements 0%. I try to kill eclipse and reopen the project and it still does the same. I do not understand why this happens. It started happening recently. Before it was working fine.
Question: I do not understand why this happens
General Answer: http://www.ihateeclipse.com/
(I may share this opinions and dont think Eclipse should be called a IDE but that wont fix your problem - hence lets proceed with possible workarounds).
Possible Workarounds:
1.) Starting eclipse in clean mode How to run eclipse in clean mode? and what happens if we do so?. (This solved aprox. 80% of my continuously returning 'I messed up my own state' issues I experienced).
2.) If that doesnt help - you would have to stop eclipse, identify the according files (or just any files holding such information) and delete them manually, then restart eclipse. Like I still encounter issues with my "Search Type" (Ctrl+T) and have to delete the files like described here Eclipse type hierarchy not always working (unfortunately I don't know anything about files regarding your current issue - so feel free to downvote my "answer" since its not directly answering your question).
The best things I found about "the full reset" seem to be: http://letsgetdugg.com/2009/04/19/recovering-a-corrupt-eclipse-workspace/ or http://blog.pdark.de/2011/09/02/restoring-a-corrupted-workspace-in-eclipse/ (Note: I haven't verified the described behaviors).
3.) Recreate Workspace - delete any eclipse belongings like the .metadata folder and keep only belongings of your project (e.g. sources, resources etc.). Then create a new eclipse project based on you existing project sources).
4.) If Steps 1-3 failed consider reinstalling Eclipse (include above Step 3 in this process again) or switching to a proper IDE that can at least handle its own state.
5.) I experienced rare cases where in the end such things were triggered by me rather than occurred magically out of nowhere by eclipse - I don't see any possibility on how you could manage that in your case unless you messed around with the eclipse source itself).
Hope this helps - Even thus the SO community is big I experienced way better results asking the eclipse developer community directly when it came to such specific issues (you however oftenly get a link to a open Bug ... that they created because of your question) and ended up "just importing into a new eclipse workspace from existing sources" whenever I experienced such issues lately (It takes me about 5 minutes to checkout our sources, start Eclipse with -clean as default and import existing Maven projects solving any eclipse-only issue - while each of those eclipse-issues can take days to be solved without any further advantage for my daily business)