Is JDO dead?

[Scott Selikoff]

I noticed most of the questions in this forum relate to Hibernate, but is anyone using JDO much?

I spent a lot of time working with JDO/KODO and thought it had some nice features. From my brief understanding of Hibernate, the technologies appear almost identical as JDO. Anyone who switched from JDO to Hibernate have any stories to share about the reason why they switched and whether transitioning (both of developer knowledge and code base) was difficult?
[ December 19, 2005: Message edited by: Scott Selikoff ]

[Pj Murray]

OK - this looks like flame bait. But I'll step in to defend the vendors that have invested a lot of time and effort in developing some very fine JDO products.

The JDO products are evolving and improving all the time. There are very few that are now JDO-only. Some have gone a completely different direction (look at Xcalia), while other are going to support EJB 3.0 data persistence.

If you are already familiar with JDO, you will have not problem with EJB 3.0 data persistence when the specification is ready (and has stabilized, perhaps after a few revisions, like JDO has).

You might also like to consider that the vast major of data access in Java is still done with JDBC.

[Erik Bengtson]

. From my brief understanding of Hibernate, the technologies appear almost identical as JDO

Hibernate is catching up with JDO features that exist for a long time either in the standard or as vendors extensions.

You can compare hibernate change log to JDO products.

Do you have a special reason to think in migrating from JDO to Hibernate?

[Scott Selikoff]

I'm more of a spectator these days. I just noticed the 'buzz' seems to be around Hibernate and JDO seems to have been absorbed in EJB 3.0. Was wondering if pure JDO is still a hot area for anyone.

[Pj Murray]

Originally posted by Scott Selikoff:
I'm more of a spectator these days. I just noticed the 'buzz' seems to be around Hibernate and JDO seems to have been absorbed in EJB 3.0. Was wondering if pure JDO is still a hot area for anyone.

The hype cycle at the moment has without doubt moved away from JDO and on to Hibernate. I expect that it will move again to EJB 3.0 data persistence next year if the final version of the specification is solid.

But that does not change the fact that up to 90% of database access in Java uses JDBC.... without any fuss or hype.

[stu derby]

Originally posted by Scott Selikoff:
I noticed most of the questions in this forum relate to Hibernate, but is anyone using JDO much?

[ December 19, 2005: Message edited by: Scott Selikoff ]

At JavaOne this year, the guys at SolarMetric's booth were generally kept busy; 2 or 3 times the queue was long enough that I put off trying to talk to them, finally squeezed in a chat on the last day.

The 2 open source JDO implementations (TJDO and JPOX) are also active, working on implementing the 2.0 specification. They (we - I'm associated w/ TJDO) have been painfully slow getting it out the door so far though...

The "buzz" certainly seems to have moved on, but there's some long-term commitment to the technology still out there.

[Scott Selikoff]

Don't get me wrong, I really like JDO as was Solarmetric, I'm just inquiring about current trends these days. There seems to be a strong convergence of object relational mapping technology via JDO, Hibernate, and EJB 3. Some Hibernate discussions or talks sound identical to JDO discussions I've heard. On the plus, it sounds switching between the mapping tools will be fairly straightforward since they are share certain similarities.

[Eric Samson]

When you have to deal with ORM, JDO 2 and EJB 3 are quite similar.
Most popular JDO products will certainly also support EJB 3, and in the meantime the both standards will certainly converge.

Now, what is nice with JDO is that it is not limited to relational databases. There are several robust JDO implementations on the market with a decent customer base, and I see no reason for vendors to deprecate support for JDO.

You also have to track SDO.
This is not POJO related but is interesting if you consider SOA.

Best Regards, Eric.