On 20 Dec (17:58), Mark Woon wrote: > >Yes, but closing/disconnecting the Session is _not_ the real problem. > >The problem is: How and where does the Filter/Observer get and store the > >Session to do its work? > > > > > > Ah. I'm storing it in the request attributes. If a page needs a > Session, it checks to see if one already exists in the request > attributes. If it doesn't, it creates one and sticks it into the > request attributes. At the end, the filter checks to see if the Session > exists, and if so, closes it. Isn't this a relatively simple way of > doing it?
It is, in a two-tiered approach. It's a lot more difficult and complex if you are modelling with three tiers, where the Hibernate Session is about 5 to 15 method calls in the stack further down than the HttpRequest. It's impractical to pass the Request in every method call. Some applications don't even have an HttpRequest or a HttpSession, because they are not web based ;) You are using the Requst as a Container, that travels through the whole system, which is OK with a JSP -> Servlet -> Hibernate approach. In complex scenarios, you'd like to decouple this: The Persistence Layer shouldn't know anything about the Presentation Layer (so this would be really bad design: passing the HttpRequest down to the Persistence Layer). You need a different, more abstract Container for this kind of architecture. You'll also need a different mechanism to cleanup/close open resources with the complex transaction handling/configuration that is possible in a three-tiered application. Some people mentioned that they implemented applications with Hibernate and put them in production. I've achieved that too, but only the classic JSP/Servlet/DataAccess Webapp. Has anyone implemented a three-tier system with Hibernate and lazy collections yet? -- Christian Bauer [EMAIL PROTECTED] ------------------------------------------------------- This SF.NET email is sponsored by: The Best Geek Holiday Gifts! Time is running out! Thinkgeek.com has the coolest gifts for your favorite geek. Let your fingers do the typing. Visit Now. T H I N K G E E K . C O M http://www.thinkgeek.com/sf/ _______________________________________________ hibernate-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/hibernate-devel
