[seam-dev] [seam-persistence] ManagedPersistenceContextExtension

[Mark Struberg]

Hi folks!

While reviewing an OWB bug report, 2 questions came up:

a.) EnvironmentUtils#isEEEnvironment() relies on the absence of 'javax.ejb.Stateless' to decide if a PersitenceUnit gets injected or if you need to do it yourself. I think this is an unrelieable assumption. E.g. there are a few Extensions which emulate Stateless Session beans via a CDI Extension by morphing them into @ApplicationScoped.

b.) in ManagedPersistenceContextExtension#registerManagedPersistenceContext you register the bean for the EntityManager as passivationCapable. This is never _never_ NEVER true. The EntityManager is not Serializable! There is imo no way to have an EntityManager in a bean scoped other than @RequestScoped or shorter (e.g. @TransactionalScoped). Any other trick is not working in a portable way. This is mainly caused by JPA still supporting pessimistic locking (_real_ locks in the database) as first class citizens. 

But I'd be happy if anyone could enlighten me and tell us how it works ;) 

LieGrue,
strub