If you could send the source for PersistenceService, and details about how you 
invoke it if the method takes any arguments, that would be very useful.

-Patrick

-- 
Patrick Linskey
BEA Systems, Inc. 

_______________________________________________________________________
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or entity named in this message. If you are not the intended recipient,
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> -----Original Message-----
> From: Hans J. Prueller [mailto:[EMAIL PROTECTED] 
> Sent: Tuesday, February 27, 2007 9:44 PM
> To: open-jpa-dev@incubator.apache.org
> Subject: AW: EMF JNDI lookup is starting openJPA every time - 
> was: Howto integrate JPA within EJB2.1 session beans? 
> 
> >> -The name used for the lookup is defined to return an 
> instance of the 
> >> object that might be shared. The name java:comp/ORB is such a name.
> 
> does this mean that the name/key with which the EMF is bound into JNDI
> affects the sharing/non-sharing of the bound instance?
> 
> currently the JNDI-string our test-implementation definitely does not
> comply to any conventions (it's not like "java:comp/.." it's 
> rather some
> tests string like "here/comes/thejndi/name") - could that be 
> the problem in
> our case?
> 
> I'm not sure if I followed the whole discussion completely 
> ... It seems
> that you might have found another reason for the behaviour? 
> Is this clear
> already or is it still required to send more detailed stuff 
> from our side?
> 
> regards,
> hans
> 
> > -----Ursprüngliche Nachricht-----
> > Von: Pinaki Poddar [mailto:[EMAIL PROTECTED]
> > Gesendet: Dienstag, 27. Februar 2007 18:48
> > An: open-jpa-dev@incubator.apache.org
> > Betreff: RE: EMF JNDI lookup is starting openJPA every time 
> - was: Howto
> > integrate JPA within EJB2.1 session beans?
> > 
> >  > But maybe something funky is happening with JNDI serializing the
> > factory and then deserializing it or something.
> > 
> > >From  J2EE 1.4 spec, page 59 (J2EE.5.2 Java Naming and Directory
> > Interface:
> > 
> > In general, lookups of objects in the JNDI java: namespace 
> are required to
> > return a new instance of the requested object every time. 
> Exceptions are
> > allowed for the following:
> > - The container knows the object is immutable (for example, 
> objects of
> > type java.lang.String), or knows that the application can't 
> change the
> > state of
> > the object.
> > -The object is defined to be a singleton, such that only 
> one instance of
> > the object may exist in the JVM.
> > -The name used for the lookup is defined to return an 
> instance of the
> > object that might be shared. The name java:comp/ORB is such a name.
> > 
> > In these cases, a shared instance of the object may be 
> returned. In all
> > other cases, a new instance of the requested object must be 
> returned on
> > each
> > lookup.
> > 
> > 
> > Pinaki Poddar
> > BEA Systems
> > 415.402.7317
> > 
> > 
> > -----Original Message-----
> > From: Patrick Linskey [mailto:[EMAIL PROTECTED]
> > Sent: Monday, February 26, 2007 11:11 PM
> > To: open-jpa-dev@incubator.apache.org
> > Subject: RE: EMF JNDI lookup is starting openJPA every time 
> - was: Howto
> > integrate JPA within EJB2.1 session beans?
> > 
> > It should be going through the following code:
> > 
> >     public static OpenJPAEntityManagerFactory 
> createEntityManagerFactory
> >         (String jndiLocation, Context context) {
> >         if (jndiLocation == null)
> >             throw new NullPointerException("jndiLocation == null");
> > 
> >         try {
> >             if (context == null)
> >                 context = new InitialContext();
> > 
> >             Object o = context.lookup(jndiLocation);
> >             return (OpenJPAEntityManagerFactory)
> > PortableRemoteObject.narrow(o,
> >                 OpenJPAEntityManagerFactory.class);
> >         } catch (NamingException ne) {
> >             throw new ArgumentException(_loc.get("naming-exception",
> >                 jndiLocation), new Throwable[]{ ne }, null, true);
> >         }
> >     }
> > 
> > I don't see anything in there that would be causing a 
> creation to happen.
> > But maybe something funky is happening with JNDI 
> serializing the factory
> > and then deserializing it or something.
> > 
> > Do you have any means of getting a stack from where the creation is
> > happening? It'd be great to get a bit more context about 
> what's going on.
> > 
> > -Patrick
> > 
> > --
> > Patrick Linskey
> > BEA Systems, Inc.
> > 
> > 
> ______________________________________________________________
> _________
> > Notice:  This email message, together with any attachments, 
> may contain
> > information  of  BEA Systems,  Inc.,  its subsidiaries  and 
>  affiliated
> > entities,  that may be confidential,  proprietary,  
> copyrighted  and/or
> > legally privileged, and is intended solely for the use of 
> the individual
> > or entity named in this message. If you are not the 
> intended recipient,
> > and have received this message in error, please immediately 
> return this by
> > email and then delete it.
> > 
> > > -----Original Message-----
> > > From: Hans J. Prueller [mailto:[EMAIL PROTECTED]
> > > Sent: Saturday, February 24, 2007 10:36 PM
> > > To: open-jpa-dev@incubator.apache.org
> > > Subject: EMF JNDI lookup is starting openJPA every time -
> > > was: Howto integrate JPA within EJB2.1 session beans?
> > >
> > > Hi together, Patrick,
> > >
> > > the code you suggested for doing a helper method that 
> deals with the
> > > EMF JNDI lookup and the EM creating within our J2EE1.4 
> app basically
> > > works fine, but as you perhaps may remember I asked why 
> the method is
> > > called "create":
> > >
> > > EntityManagerFactory myemf =
> > > OpenJPAPersistence.createEntityManagerFactory(strJNDILocation,
> > > (Context)null);
> > >
> > > It seems that the method above really creates a NEW EMF on every
> > > invocation!
> > > I checked the logs of my application and I see the 
> following messages
> > > on every invocation of my PersistenceService.getEntityManger()
> > > method (which
> > > does the above lookup and some more ..)
> > >
> > > 2007-02-25 07:27:05,687 : PersistenceService.getEntityManager
> > > : creating a
> > > fresh
> > > , clean EntityManager from JNDI EMF.
> > > 15  lbsims  INFO   [RMI TCP Connection(35)-192.168.0.5]
> > > openjpa.Runtime -
> > > Starti
> > > ng OpenJPA 0.9.7-incubating-SNAPSHOT
> > > 15  lbsims  INFO   [RMI TCP Connection(35)-192.168.0.5]
> > > openjpa.jdbc.JDBC -
> > > Open
> > > JPA will now connect to the database to attempt to 
> determine what type
> > > of databa se dictionary to use.  To prevent this connection in the
> > > future, set your openjp a.jdbc.DBDictionary configuration 
> property to
> > > the appropriate value for your dat abase (see the 
> documentation for
> > > available values).
> > > 15  lbsims  INFO   [RMI TCP Connection(35)-192.168.0.5]
> > > openjpa.jdbc.JDBC -
> > > Usin
> > > g dictionary class
> > > "org.apache.openjpa.jdbc.sql.MySQLDictionary" (MySQL 5.0.27-c
> > > ommunity-nt ,MySQL-AB JDBC Driver 
> mysql-connector-java-5.0.4 ( $Date:
> > > 2006-10-19
> > >  17:47:48 +0200 (Thu, 19 Oct 2006) $, $Revision: 5908 $ )).
> > > 15  lbsims  INFO   [RMI TCP Connection(35)-192.168.0.5]
> > > openjpa.MetaData -
> > > Found
> > >  1 classes with metadata in 0 milliseconds.
> > >
> > >
> > > It seems that OpenJPA is now bootstrapping everytime I 
> access it. I am
> > > binding the EMF somewhen at bootstrapping time with
> > >
> > > final EntityManagerFactory emFactory = Persistence
> > >                           .createEntityManagerFactory("lbsims");
> > >
> > > Context ictx = new InitialContext();
> > > ictx.bind(PersistenceService.EMF_JNDI_LOCATION, emFactory);
> > >
> > > The lookup uses the same constants, so the EMF in JNDI should be
> > > found?
> > >
> > > EntityManagerFactory emf = OpenJPAPersistence
> > >
> > > .createEntityManagerFactory(EMF_JNDI_LOCATION, (Context) null);
> > >
> > > Any Idea what could be wrong here?
> > >
> > > regards,
> > > HANS
> > >
> > >
> > > > -----Ursprüngliche Nachricht-----
> > > > Von: Patrick Linskey [mailto:[EMAIL PROTECTED]
> > > > Gesendet: Freitag, 23. Februar 2007 18:46
> > > > An: open-jpa-dev@incubator.apache.org
> > > > Betreff: RE: TYPO? Howto integrate JPA within EJB2.1 
> session beans?
> > > > [architecture]
> > > >
> > > > Typo indeed. It should be
> > > OpenJPAPersistence.toBrokerFactory(emf). Sorry
> > > > about that.
> > > >
> > > > -Patrick
> > > >
> > > > --
> > > > Patrick Linskey
> > > > BEA Systems, Inc.
> > > >
> > > >
> > > ______________________________________________________________
> > > _________
> > > > Notice:  This email message, together with any attachments,
> > > may contain
> > > > information  of  BEA Systems,  Inc.,  its subsidiaries  and
> > >  affiliated
> > > > entities,  that may be confidential,  proprietary,
> > > copyrighted  and/or
> > > > legally privileged, and is intended solely for the use of
> > > the individual
> > > > or entity named in this message. If you are not the
> > > intended recipient,
> > > > and have received this message in error, please immediately
> > > return this
> > > > by email and then delete it.
> > > >
> > > > > -----Original Message-----
> > > > > From: Hans J. Prueller [mailto:[EMAIL PROTECTED]
> > > > > Sent: Friday, February 23, 2007 9:43 AM
> > > > > To: open-jpa-dev@incubator.apache.org
> > > > > Subject: RE: TYPO? Howto integrate JPA within EJB2.1 session
> > > > > beans? [architecture]
> > > > >
> > > > > Patrick,
> > > > >
> > > > > I'm currently trying your tip with a 
> PersistenceService util class
> > > > > doing the lookup of a synchronized entity manager. 
> The problem is
> > > > > that your sample code does not work!
> > > > >
> > > > > in fact the statement
> > > > >
> > > > > final BrokerFactory bf = OpenJPAPersistence.cast(emf);
> > > > >
> > > > > is the problem. the above "cast" does not return a 
> BrokerFactory
> > > > > instance!
> > > > >
> > > > > I am using a 2 days old nightly snapshot 0.9.7 build
> > > > >
> > > > > Where is the problem?
> > > > >
> > > > > Hans
> > > > >
> > > > > > -----Ursprüngliche Nachricht-----
> > > > > > Von: Patrick Linskey [mailto:[EMAIL PROTECTED]
> > > > > > Gesendet: Donnerstag, 22. Februar 2007 23:22
> > > > > > An: open-jpa-dev@incubator.apache.org
> > > > > > Betreff: RE: RE: Howto integrate JPA within EJB2.1
> > > session beans?
> > > > > > [architecture]
> > > > > >
> > > > > > > Unfortunately, that means that we're using a synchronized
> > > > > > > block during the lookup. If it looks like EM lookup is a
> > > > > > > scalability issue for your app, do let us know -- 
> it would be
> > > > > > > pretty straightforward to replace the 
> synchronized block with
> > > > > > > a concurrent map.
> > > > > >
> > > > > > OK, I got fed up with that synchronized block. OPENJPA-161
> > > > > tracks the
> > > > > > issue; I've got a patch that I'll submit once some more
> > > > > eyes look at it.
> > > > > >
> > > > > > -Patrick
> > > > > >
> > > > > > --
> > > > > > Patrick Linskey
> > > > > > BEA Systems, Inc.
> > > > > >
> > > > > >
> > > > > ______________________________________________________________
> > > > > _________
> > > > > > Notice:  This email message, together with any attachments,
> > > > > may contain
> > > > > > information  of  BEA Systems,  Inc.,  its subsidiaries  and
> > > > >  affiliated
> > > > > > entities,  that may be confidential,  proprietary,
> > > > > copyrighted  and/or
> > > > > > legally privileged, and is intended solely for the use of
> > > > > the individual
> > > > > > or entity named in this message. If you are not the
> > > > > intended recipient,
> > > > > > and have received this message in error, please immediately
> > > > > return this
> > > > > > by email and then delete it.
> > > > > >
> > > > > > > -----Original Message-----
> > > > > > > From: Patrick Linskey [mailto:[EMAIL PROTECTED]
> > > > > > > Sent: Thursday, February 22, 2007 8:38 AM
> > > > > > > To: open-jpa-dev@incubator.apache.org
> > > > > > > Subject: RE: RE: Howto integrate JPA within EJB2.1 session
> > > > > > > beans? [architecture]
> > > > > > >
> > > > > > > > If I understand it correct, I "just" have to 
> bind the EMF
> > > > > > > > onserver startup like.
> > > > > > > >
> > > > > > > > context.bind("my/jndi/name/for/emf",myEMFVariable);
> > > > > > >
> > > > > > > Yep.
> > > > > > >
> > > > > > > >         //does the statement below again create 
> a NEW EMF
> > > > > > > or ist this
> > > > > > > >         //just a lookup in the jndi-tree? but why is it
> > > > > > > > called "Create"
> > > > > > > >         //and not get?
> > > > > > > >         EntityManagerFactory emf = OpenJPAPersistence
> > > > > > > >             .createEntityManagerFactory(
> > > > > > > >                 "your/EMF/JNDI/location", 
> (Context) null);
> > > > > > >
> > > > > > > It's just a lookup. I'm not sure why it's called
> > > 'create'. Anyone?
> > > > > > >
> > > > > > > >         //why do I have to create a new
> > > > > > > broker/entitymanager this way?
> > > > > > > >         //is this because I have to 
> "synchronize" the SLSBs
> > > > > > > > transaction
> > > > > > > >         //context with the newly created entitymanager?
> > > > > > >
> > > > > > > Yes -- our current OpenJPAPersistence EM lookup methods
> > > > > all create new
> > > > > > > EMs. The broker code will look up one associated with
> > > the current
> > > > > > > transaction, which is what you're looking for.
> > > > > > >
> > > > > > > Unfortunately, that means that we're using a synchronized
> > > > > block during
> > > > > > > the lookup. If it looks like EM lookup is a scalability
> > > > > issue for your
> > > > > > > app, do let us know -- it would be pretty 
> straightforward to
> > > > > > > replace the synchronized block with a concurrent map.
> > > > > > >
> > > > > > > > So if understand that right I just would have to call
> > > > > > > >
> > > > > > > > PersistenceService.getEntitymanager();
> > > > > > > >
> > > > > > > > in every SLSB method (NOT in ejbCreate) when 
> needed? fine.
> > > > > > >
> > > > > > > Yep.
> > > > > > >
> > > > > > > > I really appreciate your help - it's quite complex
> > > to integrate
> > > > > > > > JPA into an existing Java2EE 1.4 AppServer
> > > environment.. *puh*
> > > > > > >
> > > > > > > Yes -- sorry about that. We should at least be creating
> > > > > > > better-designed helper methods in OpenJPA to help out with
> > > > > > > this.
> > > > > > >
> > > > > > > One alternative, of course, is to use Spring 2, 
> which does a
> > > > > > > pretty good job of JPA bootstrapping.
> > > > > > >
> > > > > > > -Patrick
> > > > > > >
> > > > > > > --
> > > > > > > Patrick Linskey
> > > > > > > BEA Systems, Inc.
> > > > > > >
> > > > > > > 
> ______________________________________________________________
> > > > > > > _________
> > > > > > > Notice:  This email message, together with any 
> attachments,
> > > > > > > may contain information  of  BEA Systems,  Inc.,  its
> > > > > > > subsidiaries  and affiliated entities,  that may be
> > > > > > > confidential,  proprietary, copyrighted  and/or legally
> > > > > > > privileged, and is intended solely for the use of the
> > > > > > > individual or entity named in this message. If 
> you are not the
> > > > > > > intended recipient, and have received this 
> message in error,
> > > > > > > please immediately return this by email and then 
> delete it.
> > > > > > >
> > > > > > > > -----Original Message-----
> > > > > > > > From: Hans Prueller [mailto:[EMAIL PROTECTED]
> > > > > > > > Sent: Thursday, February 22, 2007 4:36 AM
> > > > > > > > To: open-jpa-dev@incubator.apache.org;
> > > > > > > > open-jpa-dev@incubator.apache.org
> > > > > > > > Subject: Re: RE: Howto integrate JPA within 
> EJB2.1 session
> > > > > > > > beans? [architecture]
> > > > > > > >
> > > > > > > > Patrick,
> > > > > > > >
> > > > > > > > thank you for that tip. To be true, I was not aware of
> > > > > > > > lifecycle related problems between my SLSBs and 
> JPA - thank
> > > > > > > > you for that hint. As I want to avoid working with
> > > > > > > > ThreadLocal (simply because I didn't work with 
> ThreadLocals
> > > > > > > > yet) I would prefer the JNDI-EMF based approach.
> > > > > > > >
> > > > > > > > If I understand it correct, I "just" have to 
> bind the EMF
> > > > > > > > onserver startup like.
> > > > > > > >
> > > > > > > > context.bind("my/jndi/name/for/emf",myEMFVariable);
> > > > > > > >
> > > > > > > > I would be interested what the code for the
> > > > > > > > PersistenceService class does:
> > > > > > > >
> > > > > > > >
> > > > > > > >         //does the statement below again create 
> a NEW EMF
> > > > > > > or ist this
> > > > > > > >         //just a lookup in the jndi-tree? but why is it
> > > > > > > > called "Create"
> > > > > > > >         //and not get?
> > > > > > > >         EntityManagerFactory emf = OpenJPAPersistence
> > > > > > > >             .createEntityManagerFactory(
> > > > > > > >                 "your/EMF/JNDI/location", 
> (Context) null);
> > > > > > > >
> > > > > > > >         //why do i have to cast the EMF to a
> > > > > brokerfactory now? I
> > > > > > > >         //would guess the "broker" is something like a
> > > > > more abstract
> > > > > > > >         //concept of entitymanager(factory)?
> > > > > > > >
> > > > > > > >         //why do I have to create a new
> > > > > > > broker/entitymanager this way?
> > > > > > > >         //is this because I have to 
> "synchronize" the SLSBs
> > > > > > > > transaction
> > > > > > > >         //context with the newly created entitymanager?
> > > > > > > >
> > > > > > > >         BrokerFactory bf = OpenJPAPersistence.cast(emf);
> > > > > > > >         Broker b = bf.newBroker(
> > > > > > > >         bf.getConfiguration().getConnectionUserName(),
> > > > > > > >           bf.getConfiguration().getConnectionPassword(),
> > > > > > > >           true, // the broker is part of a JTA 
> managed tx
> > > > > > > >
> > > > > bf.getConfiguration().getConnectionRetainModeConstant(),
> > > > > > > >           true); // look for an existing Broker 
> on the tx
> > > > > > > >
> > > > > > > >         
> broker.setAutoDetach(AutoDetach.DETACH_CLOSE, true);
> > > > > > > >
> > > broker.setAutoDetach(AutoDetach.DETACH_ROLLBACK, true);
> > > > > > > >         broker.setDetachedNew(false);
> > > > > > > >
> > > > > > > >         return OpenJPAPersistence.toEntityManager(b);
> > > > > > > >     }
> > > > > > > >
> > > > > > > > So if understand that right I just would have to call
> > > > > > > >
> > > > > > > > PersistenceService.getEntitymanager();
> > > > > > > >
> > > > > > > > in every SLSB method (NOT in ejbCreate) when 
> needed? fine. I
> > > > > > > > really appreciate your help - it's quite complex to
> > > integrate
> > > > > > > > JPA into an existing Java2EE 1.4 AppServer
> > > environment.. *puh*
> > > > > > > >
> > > > > > > > regards
> > > > > > > > Hans
> > > > > > > >
> > > > > > > > -------- Original-Nachricht --------
> > > > > > > > Datum: Wed, 21 Feb 2007 08:43:20 -0800
> > > > > > > > Von: "Patrick Linskey" <[EMAIL PROTECTED]>
> > > > > > > > An: open-jpa-dev@incubator.apache.org
> > > > > > > > CC:
> > > > > > > > Betreff: RE: Howto integrate JPA within EJB2.1
> > > session beans?
> > > > > > > > [architecture]
> > > > > > > >
> > > > > > > > > Another common technique is to get an EMF into
> > > JNDI, either
> > > > > > > > by using a
> > > > > > > > > startup hook or deploying OpenJPA as a JCA RAR.
> > > > > > > > >
> > > > > > > > > Are you looking to integrate OpenJPA with your
> > > current managed
> > > > > > > > > transaction? If so, I'd be careful about 
> creating an EM in
> > > > > > > > ejbCreate(),
> > > > > > > > > as its lifecycle is related to the life of the SLSB,
> > > > > not to the
> > > > > > > > > transactional context (the SLSB might be 
> pooled). So, I'd
> > > > > > > > just try to
> > > > > > > > > get the EMF into JNDI when the server starts
> > > (creating EMFs
> > > > > > > > is slow).
> > > > > > > > > Then, you could avoid having to use your own 
> ThreadLocal
> > > > > > > > work by using
> > > > > > > > > the internal OpenJPA BrokerFactory APIs:
> > > > > > > > >
> > > > > > > > > public class PersistenceService {
> > > > > > > > >     public static EntityManager getEntityManager() {
> > > > > > > > >         EntityManagerFactory emf = OpenJPAPersistence
> > > > > > > > >             .createEntityManagerFactory(
> > > > > > > > >                 "your/EMF/JNDI/location", 
> (Context) null);
> > > > > > > > >         BrokerFactory bf = 
> OpenJPAPersistence.cast(emf);
> > > > > > > > >         Broker b = bf.newBroker(
> > > > > > > > >             
> bf.getConfiguration().getConnectionUserName(),
> > > > > > > > >             
> bf.getConfiguration().getConnectionPassword(),
> > > > > > > > >             true, // the broker is part of a JTA
> > > managed tx
> > > > > > > > >
> > > > > > > bf.getConfiguration().getConnectionRetainModeConstant(),
> > > > > > > > >             true); // look for an existing Broker
> > > on the tx
> > > > > > > > >
> > > > > > > > >         // do some JPA configuration setup. Logic
> > > stolen from
> > > > > > > > >         // EntityManagerFactoryImpl.
> > > > > > > > >
> > > broker.setAutoDetach(AutoDetach.DETACH_CLOSE, true);
> > > > > > > > >
> > > > > broker.setAutoDetach(AutoDetach.DETACH_ROLLBACK, true);
> > > > > > > > >         broker.setDetachedNew(false);
> > > > > > > > >
> > > > > > > > >         return OpenJPAPersistence.toEntityManager(b);
> > > > > > > > >     }
> > > > > > > > > }
> > > > > > > > >
> > > > > > > > > Meanwhile, we really should add a couple new
> > > > > OpenJPAPersistence /
> > > > > > > > > OpenJPAEntityManagerFactory methods to help out with
> > > > > this type of
> > > > > > > > > bootstrapping.
> > > > > > > > >
> > > > > > > > > -Patrick
> > > > > > > > >
> > > > > > > > > --
> > > > > > > > > Patrick Linskey
> > > > > > > > > BEA Systems, Inc.
> > > > > > > > >
> > > > > > > > >
> > > > > > > >
> > > ______________________________________________________________
> > > > > > > > _________
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> > > > > > > > > > -----Original Message-----
> > > > > > > > > > From: Hans Prueller [mailto:[EMAIL PROTECTED]
> > > > > > > > > > Sent: Wednesday, February 21, 2007 1:02 AM
> > > > > > > > > > To: open-jpa-dev@incubator.apache.org
> > > > > > > > > > Subject: Howto integrate JPA within EJB2.1
> > > session beans?
> > > > > > > > > > [architecture]
> > > > > > > > > >
> > > > > > > > > > Hi together,
> > > > > > > > > >
> > > > > > > > > > I'm sorry for bothering you with numerous basic
> > > questions
> > > > > > > > > > regarding OpenJPA and its usage but I have 
> to migrate
> > > > > > > > > > existing CMP EJBs to migrate within short time
> > > to OpenJPA as
> > > > > > > > > > we're having stability issues with the current
> > > CMP engine.
> > > > > > > > > >
> > > > > > > > > > One last question I'd like to ask is regarding the
> > > > > > > > > > recommended architecture of using OpenJPA 
> within EJB2.1
> > > > > > > > > > Stateless sessino beans:
> > > > > > > > > >
> > > > > > > > > > I need to work with persistence i.e. the 
> EntityManager
> > > > > > > > > > throughout all the session beans methods so my
> > > idea is to:
> > > > > > > > > >
> > > > > > > > > > - create a EntityManagerFactory in the
> > > ejbCreate() method
> > > > > > > > of the SLSB
> > > > > > > > > > - and also create the EntityManager itself in the
> > > > > > > > > > ejbCreeate() method and store it as a 
> member variable
> > > > > > > of the SLSB
> > > > > > > > > > - this would allow easy access within the SB's
> > > methods by
> > > > > > > > > > just using the already initialized entity
> > > manager varialbe
> > > > > > > > > > em.createNamedQuery() .. etc. etc.
> > > > > > > > > > - clean up should be performed in the 
> ejbRemove() method
> > > > > > > > of the SLSB
> > > > > > > > > >
> > > > > > > > > > I think doing so will allow migratino to
> > > openJPA with less
> > > > > > > > > > work than doing the whole lookup procedure in
> > > every method
> > > > > > > > > > separately.
> > > > > > > > > >
> > > > > > > > > > what do you think? are there any pitfalls i've
> > > overlooked?
> > > > > > > > > >
> > > > > > > > > > thank you for your ideas!
> > > > > > > > > >
> > > > > > > > > > regards
> > > > > > > > > > Hans
> > > > > > > > > > --
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> > > > > > > >
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> > > > > > >
> > > > >
> > > > >
> > >
> > >
> 
> 

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