This morning I've done about 60 minutes work. The other 120 minutes was spent watching the 'busy' pointer, waiting for eclipse to do.....something.
Experience tells me it's something mylyn related. Unfortunately Juno comes with mylyn, and it's not easy to remove.
Or is it?
Preferences->Java->editor->content assist->advanced.
Deselect anything marked 'task oriented', and replace it with the non task-oriented version.
Now go into your eclipse plugins folder and remove anything to do with mylyn.
Hurray! My IDE works again :-)
