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From titou10 <titou10.tito...@gmail.com>
Subject Re: Extended EntityManager
Date Sat, 18 Apr 2015 11:34:27 GMT
Mark,
We keep the EM in the conversation scope, but we expose it at the request scope
A new EM is created only when there is no one currently in the conversation scope, so we have
the same EM for the duration of the 
conversation, short or long:
It is very close to what Seam 2 did

@ConversationScoped
public class EntityManagerProducer {

=====>   private transient EntityManager em;

    @PersistenceUnit
    private EntityManagerFactory    emf;

    @Produces
    @RequestScoped
    protected EntityManager creerEntityManager() {
======>      if (em == null) {
======>         em = emf.createEntityManager();
======>      }
======>      return this.em;
    }

Le 2015-04-18 01:35, Mark Struberg a écrit :
> But in your example only the bean ‚holding‘ the producer method is @ConversationScoped.
The EntityManager you create is only @RequestScoped (which is good imo!), right? So the lifecycle
of the EM will effectively be 1-per-prequest.
>
> LieGrue,
> strub
>
>
>> Am 17.04.2015 um 22:30 schrieb titou10 <titou10.titou10@gmail.com>:
>>
>> I can't comment on the DS/JPA example, but that's why the solution we use keeps the
EM instance in a variable, variable held in the @ConversationScoped Bean that "contains" the
producer that "exposes" this EM in the @RequestScope
>> The EM is opened/closed only on conversation boundaries (short or long) , very similar
to what Seam 2 does (In CDI,  Conversations length is not exactly the same as in Seam Conversations)
>> Denis
>>
>> Le 2015-04-17 16:05, Ludovic Pénet a écrit :
>>> Thanks to everybody for your valuable adviced.
>>>
>>> I ended with an @ApplicationScoped EntityManagerProducer, producing @ViewAccessScoped
ExtendedEntityManager.
>>> ExtendedEntityManager is identical to DS JPA example.
>>>
>>> So, something very close from DS JPA page example.
>>>
>>> http://deltaspike.apache.org/documentation/jpa.html#_extended_persistence_contexts
>>>
>>> In fact, I am still a bit puzzled by DS JPA example, because the EntityManager
it produces is @RequestScoped.
>>>
>>> So, when I basically copied/pasted it, the EM was just opened and closed on every
request. And, for an example, session was closed when some hibernate proxies were accessed
during serialization...
>>>
>>> Do I miss something obvious, or should the doc rather mention that one should
use a scope such as @ViewScoped, @SessionScoped or @ViewAccessScoped rather than @RequestScoped
?
>>>
>>> Ludovic
>>>
>>>


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