Comments on Brian Silberbauer: Google Appengine Java Test Ride

@Francis: I'm sure you figured this out already, b...

2009-04-15T16:23:11.659+02:00

@Francis: I'm sure you figured this out already, but just in case have a look here: http://groups.google.com/group/google-appengine-java/browse_thread/thread/260dd1ed946b6e11#

Basically, you will need 'register' the entity classes in the persistance.xml configuration using the 'class' element.

@Christian: Thanks for that. It would be nice if...

2009-04-14T10:42:32.842+02:00

@Christian: Thanks for that.

It would be nice if GAEJ supported a DI framework out the box, I would vote for Guice or EJB3's way of doing it (or at least using the same annotations would be an idea).

Hey. Good article. Small point - for the record, ...

2009-04-13T19:59:00.000+02:00

Hey. Good article. Small point - for the record, "google" doesn't "recommend" wrapping the persistence manager factory in a singleton - the demo and samples folks merely did so as an expedient. Generally, Google doesn't recommend singletons at all.

http://misko.hevery.com/2008/08/17/singletons-are-pathological-liars/

http://googletesting.blogspot.com/2008/05/tott-using-dependancy-injection-to.html

http://googletesting.blogspot.com/2008/08/where-have-all-singletons-gone.html

While this isn't universally held in all Google code (the GAE does have singletons you access), it is something increasingly promulgated. I would recommend using Guice or some other IoC container, and wrap a service around your persistence manager creation.

@Francis: I haven't used JPA on app engine yet. Ar...

2009-04-11T20:24:40.096+02:00

@Francis: I haven't used JPA on app engine yet. Are you sure you have the named query registered with a @NamedQuery annotation, maybe you have a typo?

On the other hand I haven't seen any reference to using named queries, try asking on the mailing list: http://groups.google.com/group/google-appengine-java/.

Nice article!!!I also have similar problem as u.no...

2009-04-11T19:50:00.000+02:00

Nice article!!!

I also have similar problem as u.
now i'm using jpa named query. however, a exception about the "named query was not found" is encountered. Do u have the same problem.? I'm pretty sure I'm doing the right thing as the same code can run on glassfish..

@dartdog: I can't show you yet, its a work in prog...

2009-04-11T17:27:29.382+02:00

@dartdog: I can't show you yet, its a work in progress of a real app. I'll let you know when it goes into beta.

@Rick: Only a pleasure, was fun. I will write a follow up as soon as I have time to work on it again.

Another thing I'd like to see added to the framework would be DI of some wort out the box. Maybe a watered down EJB container?

I've used spring before, but I want something a little lighter this time, I hear Guice works, any suggestions would be appreciated.

Thanks for the write-up! Please do let us know la...

2009-04-11T16:02:00.000+02:00

Thanks for the write-up! Please do let us know later about further experiences...

Rick

How about the link to the app on app-engine?

2009-04-11T16:01:00.000+02:00

How about the link to the app on app-engine?