So pre spring, we used version of HibernateUtil that cached the SessionFactory instance if a successful raw JDBC connection was made, and threw SQLException otherwise. This allowed us to recover from initial setup of the SessionFactory being "bad" due to authentication or server connection issues.

We moved to Spring and wired things in a more or less classic way with the LocalSessionFactoryBean, the C3P0 datasource, and various dao classes which have the SessionFactory injected.

Now, if the SQL server appears to not be up when the web app runs, the web app never recovers. All access to the dao methods blow up because a null sessionfactory gets injected. (once the sessionfactory is made properly, the connection pool mostly handles the up/down status of the sql server fine, so recovery is possible)

Now, the dao methods are wired by default to be singletons, and we could change them to prototype. I don't think that will fix the matter though - I believe the LocalSessionFactoryBean is now "stuck" and caches the null reference (I haven't tested this yet, though, I'll shamefully admit).

This has to be an issue that concerns people.