Good question, Michelle. My first interpretation when reading that
paragraph is that it would be your latter option, where XML can be
'mixed in' with annotations, overriding any that already exist on an
individual basis. As a user, I would expect this. It is especially
important when considering separating out ORM-specific metadata into
XML. For example, I would want to be able to specify *what* is
persistent in annotations, and *how*/*where* it is persisted in XML.
Speaking from my current experience with using 2.1 annotations in a
large code base, we're putting everything, including ORM metadata in
annotations. This is largely to keep things simple. It's much
easier for the uninitiated to deal with all the metadata being in
annotations in the classes they care about than having to know about,
track down, and understand the package.jdo XML. However, I can see
a day coming when we will need to deploy all or part of the code base
against multiple, somewhat differing data models, and it would be
nice to be able to override the hard-coded ORM annotations in XML.
Hopefully that doesn't make for an implementation nightmare :-)
At any rate, thanks for bringing this up. It'll be nice to have the
spec be particular on this topic, one way or the other.
- Chris Beams
On Aug 4, 2007, at 2:02 PM, Michelle Caisse wrote:
Hi Craig,
Chapter 19 says: "If xml metadata is defined for annotated classes,
fields, or properties, xml metadata overrides the annotation." I
think there needs to be further discussion about what level the
override happens on. Are all of the annotations in the class
automatically overriden if there is xml for the class, does the
override happen only for annotations for which there is a
corresponding xml element, ...?
-- Michelle
Craig L Russell wrote:
at http://db.apache.org/jdo/documentation.html
Check it out, and send comments...
Craig Russell
Architect, Sun Java Enterprise System http://java.sun.com/products/
jdo
408 276-5638 mailto:[EMAIL PROTECTED]
P.S. A good JDO? O, Gasp!
