Hi I had same problem , i delete .metadata in workspace subdirectory in WSAD\eclipse\workspace and restart the WSAD . -doing this is almost equal to reinstalling WSAD- I hope you get your jsp editor working.
Thankyou Masoud, but deleting .metadata is resulting in losing pointers to my Source Code Repository and project altogether, I remember there is a particular file under some folder which might be corrupted. I would appreciate if somebody could be able to tell the particular file I could fix or delete.
Sometimes you can repair this by closing all editors and all perspectives, exiting, restarting the machine, and reopening WSAD.
Repairing the metadata is complicated, but may be worth it. Make a backup copy of your .metadata folder before you start mucking with it. Your first option is to try a fresh folder generated via a -data flag on a command line, then copy the .plugins folder over the new versions to save your preferences. Beyond that, try replacing files 1 by 1.
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