I am reviewing my Hibernate code, and am getting quite tired of writing the same sort of
close-session-get-another-one-in-case of exception.

There are several situations where I assume that the Session instance remains intact :
1) Attempting to load a record that doesnt exist
2) Attempting to save a record that already exists
3) Attempting to delete a non existent record

Is there any problem in using the session after one of these occurs ?
Is it possible to check HibernateException to see if such non-fatal issue caused it ?

And, is it possible to leave the session anyway, and check to session later to see if it needs to be replaced with a fresh one ?

Cheers,

Henrik

in addition,

when cleaning up according to the ThreadLocal pattern under j2ee servlets. Currently I close the current session after any given request using a filter.

That will only clean up sessions of the current thread. Isn't it possible for the server to loose connection and therefore not respond, throw an exception going past the reminder of the filter, and never clean up the session in that thread. I know it would be rare, but I suppose that would be a memory leak.

fix: try { chain.doFilter.. } finally { close current session }

Good point, and I believe that Jeff Schnitzer's Servlet Filter approach is pretty consistent about this. Check out http://www.hibernate.org/43.html for more info.
Scott

I think ALL hibernate exceptions are considered fatal and the session should always be trashed after catching one. It may be that the current implementation means certain errors like the ones you mention are survivable but there is no guarantee that future implementation changes won't break the functionality you are relying on now.

If so, I think there would be a good argument for either of:

1) Flagging the session object as invalid or automatically close it if it is no longer usable
2) Flagging the exception, so the catch may check
3) Having specialized versions of HibernateException for the non-fatal exceptions, so one may catch those and be less agressive in killing the session

I imagine that these are trivial improvement of Hibernate

Henrik

ObjectNotFoundException and StaleObjectStateException are recoverable.

In case anyone stumbles onto this older thread, more recent Hibernate lore says to throw away the session when any HibernateException occurs. One example:

http://forum.hibernate.org/viewtopic.php?t=967230&start=0&postdays=0&postorder=asc