cayenne-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Gilberto C Andrade <gilbert...@secad.to.gov.br>
Subject Re: Cayenne POJO enhancer
Date Thu, 25 Oct 2007 18:41:03 GMT
Andrus Adamchik wrote:
> 
> On Oct 25, 2007, at 7:36 PM, Gilberto C Andrade wrote:
>>> In other words if that's an offer to work together with Cayenne
>>> developers to address the things missing or broken in the JPA provider,
>>> we will gladly accept such help.
>>
>> That's the intention! We hope to help and not bring more problem!
> 
> Very cool. I would suggest to subscribe to the Cayenne dev list when
> things comes to discussion of the needed Cayenne improvements.
> 
>> We don't want to use the hibernate tags! Our idea was ignore them and
>> map it by hand or with cayenne help.
>> Just think as there not exists any hibernate tag, only the POJO api.
>> How can we map and use them as is?
> 
> ....
> 
>>> As for the documentation, I suggest the JPA spec [1] for the full list
>>> of annotations.
>> All this new thing are annotations dependent?
> 
> Ok, I think now I see what you are getting at. We currently advertise
> using either traditional Cayenne API (i.e. inherit from
> CayenneDataObject) or JPA-compatible POJOs (that require either
> annotations or JPA XML descriptor).
After take a look at the ejb-3_0-fr-spec-persistence.pdf file, I found
how we can do it:
[code]
An object/relational mapping XML file contains mapping information for
the classes listed in it. A object/relational mapping XML file named
orm.xml may be specified in the META-INF directory in the root of the
persistence unit or in the META-INF directory of any jar file referenced
by the persistence.xml. Alternatively, or in addition, other mapping
files may be referenced by the map-ping-file elements of the
persistence-unit element, and may be present anywhere on the class path.
[/code]

Mainly this one:
[code]
 An orm.xml file or other mapping file is loaded as a resource by the
persistence provider. If a mapping file is specified, the classes and
mapping information specified in the mapping file will be
used.
[/code]

Will the cayenne modeler support the ability to add Persistent Types
(Entities, etc) to the ORM XML?
This link
http://www.eclipse.org/webtools/releases/2.0/newandnoteworthy/jpa.php
(go to the end and see), illustrate the idea.
> 
> But there is a less-known middle-ground option - POJO's working with
> traditional Cayenne API. If I understand correctly you'd prefer this
> option? As we've placed most of the 3.0 effort into JPA, this has been
> somewhat neglected, but it is still a workable solution. Let me
> elaborate on it a bit:
> 
> * It does NOT require annotations.
> * It does require regular Cayenne mapping created with CayenneModeler.
> * It does require class enhancement.

But how can we change/customize the mapping, since we are dealing with a
legacy database?

> Here is one simple example - our POJO integration tests subproject:
> 
>   https://svn.apache.org/repos/asf/cayenne/main/trunk/itests/pojo/
> 
> As you may see, it has a regular Cayenne .map.xml on the classpath, and
> starts with the agent option: "-javaagent:cayenne-agent-3.0-SNAPSHOT.jar".
> 
> Andrus
> 
> 
> 
> 
> 
> 


Mime
View raw message