Re: [eclipselink-users] Dynamic FetchGroup usage

[James Sutherland <jamesssss@xxxxxxxxx>]

The error seems to indicate that you have the same persistence.xml file on
your classpath twice.  You should remove the src directory from your
classpath.  The error should probably be a warning though, so you could log
a bug for it, I'm surprised JPA works at all with your classpath as I would
expect the same error later without weaving.

Instead of dynamic weaving you could also use static weaving, or implement
the FetchGroupTracker interface yourself directly in your Entity class (or a
common superclass).



MarcNuri wrote:
> 
> Thanks for your reply James.
> 
> I spent a while investigating the problem and I found out that my problem
> was (is) what you're saying, you need weaving enabled to be able to use
> FetchGroups. By the way, that is clearly explained in the javadoc (my
> fault not reading thoroughly).
> 
> The problem is that I'm not using weaving. I came to FetchGroups in first
> place because of the deprecation alert in the "addPartialAttribute(...)"
> method in org.​eclipse.​persistence.​queries.​ObjectLevelReadQuery. The
> api clearly states the following: "Deprecated. since EclipseLink 2.1,
> partial attributes replaced by fetch groups.".
> The thing is that you can use partial attributes without weaving but
> that's not the case with the replacement approach via FetchGroups.
> 
> So my question now is if this means that if I update to future versions of
> EclipseLink I'm going to loose functionality or in the other hand there is
> something else I can do (apart from enabling weaving).
> 
> To answer why I'm not using weaving: Weaving is really easy to enable, you
> just have to add " -javaagent:(path to eclipselink.jar)", unfortunately in
> my development environment (Netbeans), this is the exception I get when
> turning on the feature:
> ++++++++++++++++++++++++++++++++++++++++++
> Exception Description: Persistence unit $puName is defined in both
> URL:file:/F:/$path/build/classes/ and URL:file:/F:/$path/src/. Cannot have
> several persistence units with the same name loaded by the same
> classloader.
> ++++++++++++++++++++++++++++++++++++++++++
> I've found no easy way of correcting this error and waving is not a real
> priority in my projects (for now).
> 
> Regards
> 
> P.S. If anyone knows a way I can bypass any of the prior issues, help is
> appreciated.
> --
> Marc Nuri
> 


-----
http://wiki.eclipse.org/User:James.sutherland.oracle.com James Sutherland 
http://www.eclipse.org/eclipselink/
 EclipseLink ,  http://www.oracle.com/technology/products/ias/toplink/
TopLink 
Wiki:  http://wiki.eclipse.org/EclipseLink EclipseLink , 
http://wiki.oracle.com/page/TopLink TopLink 
Forums:  http://forums.oracle.com/forums/forum.jspa?forumID=48 TopLink , 
http://www.nabble.com/EclipseLink-f26430.html EclipseLink 
Book:  http://en.wikibooks.org/wiki/Java_Persistence Java Persistence 
Blog:  http://java-persistence-performance.blogspot.com/ Java Persistence
Performance 
-- 
View this message in context: http://old.nabble.com/Dynamic-FetchGroup-usage-tp30328424p30405696.html
Sent from the EclipseLink - Users mailing list archive at Nabble.com.