> Chris Colman schrieb: > > > The obvious benefit in such an approach is that your POJO model and the > > services that you provide to implement business rules etc., remain > > completely portable to different persistence engines - ie., no vendor > > lock in. > > well, i thought that was JPA was all about !?
No, definitely not! JPA was all about creating a standard that Hibernate could conform to. Remember there *already* was a standard for Java persistence: JDO. JDO implementations such as JPOX and others implement both JDO (obviously) and JPA but it is not possible for Hibernate to provide all the features of JDO and so it could never implement the JDO standard - hence a less powerful standard had to be created so that Hibernate could play the "standards" game. Enough of the history lesson already ;) > > As well as "wrapping" the various persistence engines it also provides > > dependency injection without resorting to separate XML/bean mania - it's > > all done very quickly and concisely and automatically in Java - > > Thanks, that´s what guice is great for, and it is really neatly > integrated with wicket. Yes, exPOJO and guice are great alternatives to a heavyweight and XML based approach like Spring. exPOJO, being a lightweight implementation of the "exposed POJO domain model pattern" has the benefit of making it easy to port apps between Hibernate, JDO and JPA without changing any of your model code or 'Service' classes. You only need to implement an engine specific Repository class as repositories are the only classes that contain engine specific API calls - ie., mainly the queries. If the slow performance of Hibernate's "reflection based" dirty state checking on large object graphs has you worried then you can quickly change your underlying persistence engine over to a "byte code enhanced" solution, like for example JPOX, with the lightning fast dirty state checking and other performance gains that brings. > > > http://expojo.com > > I´ll take a look anyway, thanks. > > cu uwe > > -- > > THOMAS DAILY GmbH > Adlerstraße 19 > 79098 Freiburg > Deutschland > T + 49 761 3 85 59 0 > F + 49 761 3 85 59 550 > E [EMAIL PROTECTED] > www.thomas-daily.de > > Geschäftsführer/Managing Directors: > Wendy Thomas, Susanne Larbig > Handelsregister Freiburg i.Br., HRB 3947 > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
