How to implement this pattern with servlet filters?

At the moment i have a filter class that perform session.connect / session.disconnect. Where session is retrieved with thread local variable to ensure that it is the same hibernate session during all the httpsession.
I also have a session listener (servlet session!) to put the hibernate session in the thread.

But this pattern is not effcient because it ask a connection to the db everytime also to do things that don't need a connection to the database. How to code it better?

You are using a database pool arent you? So your connections are open all the time anyways.

You surely mean HTTP Request?


If you would use IoC framework ( like nanocontainer / nanowar ) your hibernate session would be created only when needed...

you have to know that the open session in view pattern does not open the underlying jdbc connextion at each request.

when you are obtaining a session, it is not using a jdbc connection until you're really using it (querying, reattaching,...).

session.reconnect() does not open connection?
It only obtains a connection from the connection pooler wihtout open the connection, isn't it?
Anyway the session I think blocks a connection that can't be obtained in the same time from another thread.

You surely mean HTTP Request?

No.
My HTTP session store a hibernate session which i reconnect and disconnect everytime the filter is invoked. I don't have detached object so.

this is a nice way of doing, Christian also calls it "persistent context" (i've been in the Paris training ;)) ) but be sure to use this only for a unit of work, that is to say 5 screens for example if you need 5 screens to do your job. After this, commit and close().
Of course don't forget to set flushMode.NEVER and commit transaction at each request!. If you don't do this you'll surely have write locks because of unfinished database transaction.

Don't use a hibernate session per "long" user, or you'll soon have a huge session and stale datas.

session.reconnect() just means that the session is ready to execute its job, if it has nothing to do, it will not get a jdbc connection from the pool.

_persistence_ context ;)