We once did something similar although not on the web but we also had the issue that users suddenly go away without releasing the lock.
So we gave the lock a lastAccess timestamp and allow others to override/cleanup the lock if it was older than X minutes. Whenever the lock owner edited the locked data the lastAccess timestamp of the lock has been updated to current timestamp. We also updated the timestamp using some ping requests in case the user did not actively edit the data but was still logged in and in the edit view. Thus when the user did go away without having cleaned up the lock the lock became invalid after X minutes. That way it does not really matter if you clean up the lock when the window closes as long as you are fine with it that the lock exists a little longer than the user is actually logged in to your app. -- J. -- You received this message because you are subscribed to the Google Groups "GWT Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to google-web-toolkit+unsubscr...@googlegroups.com. To post to this group, send email to google-web-toolkit@googlegroups.com. Visit this group at https://groups.google.com/group/google-web-toolkit. For more options, visit https://groups.google.com/d/optout.