Hi,

I'm starting a new project which I wish to use EJB3.
As far as I know the specification of EJB3 is not yet finalised.
If I'm using EJB3 with the current implementation i'm not sure how much changes I need to make after I develop my project halfway.

The other idea would be using EJB2(Session) plus Hibernate.
But I really hate the EJB2 ideas.

Any suggestion?

Topic comes up quite often in Java User Groups.

As of today, December 2005, there are some companies who are actually using EJB3 in production enviornments. I would be leary of this since the spec is not quite finished. But since some EJB3 containers (like JBOSS) are essentially Hibernate under the hood, then go with EJB3 if your system is not going to be mission critical for the next 6 to 8 months.

If you need to write something for production and it needs to be ready and stable for general release in the next few months, you should lean towards EJB2 + Hibernate.

Having said that, if you do not use EJB3, you will eventually need to do some Hibernate to EJB3 porting unless you want to maintain separate APIs.

I'm sure some will agree, others disagree. But that is what we found.

markricard,

my system would take at least 6 months to be built before being sent to QA. Or at least it need 1 year for a completion.

I've never used Hibernate but I like the idea of ORM very much.
As I look into the EJB3 specs it looks just great and it turns me off using EJB2 mechanism.

As there are not enough sufficient books describing EJB3 entity beans, it would be a dilemma when I am unable to find the answer for certain database mapping. As for Hibernate I can always refer to Hibernate in Action book.

So now my choices come down to:
#1. EJB3(Session Bean)+ Hibernate
#2. EJB3(Session Bean) + EJB3(Entity Bean)

Unless the EJB(Entity Bean) mapping is very similiar to Hibernate I might just be using EJB3(Entity Bean).

any opinion?

Map your persistent classes with Hibernate Annotations, use EJB3-compatible annotations whenever possible and Hibernate extensions when needed.

Write your data access code with the EJB3 EntityManager API.

All of this runs in plain JSE and does not require EJBs or an application server. However, seriously consider EJB3 session beans though, they are great. Right now the only tested integration of Hibernate Annotations and Hibernate EntityManager is with JBoss EJB3 Application Server. Others will definitely follow.

Wait a few weeks until both Hibernate Annotations and Hibernate EntityManager, and JBoss EJB3, have been updated to the latest Public Final Draft of EJB3 that just came out. Use the time to learn the spec and Hibernate stuff.

Comparable examples of XML mappings and annotations, the most time-consuming issue you will face, can be found in http://caveatemptor.hibernate.org/ - I recommend staying up-to-date with CVS there.

Christian,

excellent. This is exactly the reply I wanted.
I'll explore more for time being on annotation.