Re: [eclipselink-users] Create persistence unit programmically without p

[Philipp Kursawe <phil.kursawe@xxxxxxxxx>]

James Sutherland wrote:
> I suppose that is the main reason you need a persistence.xml, to define the
> set of classes/classpath.  I don't think it is possible to deploy JPA
> without a persistence.xml.  You could log an enhancement to allow passing
> the class list, or orm.xml file with the persistence properties Map, but you
> would still need to access the EclipseLink provider directly as JPA
> Persistence requires a persistence.xml to know the provider.

Well in the good old days of Hibernate I could just create a session and 
add my classes to it on the fly. Seems that never made it into SUNs JPA 
specs. However I have completely removed the provider from the 
persistence.xml and hand it to EL using the properties of the EMF. This 
seems to work ok. The only thing left in the persistence.xml is the spec 
of the classes. I guess it would not be too hard to expose the method 
that parses the classname in EL and creates the ClassDescriptor for it 
as a public method of the EL JPA Provider.

Still, JPA inside a dynamic OSGi environment is painful. Hibernate was 
much more flexible even 4 years ago.

> philk wrote:
> > Hello,
> >
> > I want to create a persistence unit with out using the persistence.xml. I
> > am
> > already feeding EL all the "eclipselink" properties for the database
> > connection and the class loader. The last thing I struggle to find is, how
> > to feed EL the entity classes that the PU should be aware of. How would I
> > do
> > that?
> >
> > Thanks,
> > Phil