geronimo-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Christopher Blythe" <cjblyth...@gmail.com>
Subject Re: Daytrader EJB3 development
Date Thu, 15 Mar 2007 20:22:55 GMT
All...

In order to work on EJB3 changes to Daytrader without disrupting trunk, I
have created branches/ejb3 as a sandbox. I also committed a host of EJB3
based primitives... The project compiles, but I have no idea how they'll
respond in G at the moment.

Links to the primitives can be accessed at...

http://localhost:8080/daytrader/ejb3_prims.html

The primitives include various combinations of stateful and stateless
session beans, entities with various load properties (eager, lazy, etc.) and
and MDB sample.

In order to swizzle these in, I created two new packages under the ejb
module...

org.apache.geronimo.samples.daytrader.ejb3
org.apache.geronimo.samples.daytrader.ejb3.prims

and one new package to the web module.

org.apache.geronimo.samples.daytrader.web.prims.ejb3

Eventually, i think we will need to do some refactoring of the packages,
etc. before everything is finalized.


On 3/8/07, David Jencks <david_jencks@yahoo.com> wrote:
>
>
> On Mar 8, 2007, at 9:48 AM, Christopher Blythe wrote:
>
> > All...
> >
> > Thanks to the efforts of David Jencks, Daytrader 2.0 (trunk)
> > already contains a JPA-based implementation of the Trade services
> > wrapped in an EJB 2.1 stateless session bean. As additional EJB3
> > and EE5 features are delivered in Geronimo (and other appservers),
> > Daytrader should follow suit by exploiting the entire EJB3 and EE5
> > programming model. This would primarily involve conversion of the
> > stateless session beans and MDBs to EJB3. I have already begun some
> > of this work using another development platform that already
> > supports EE5.
> >
> > For the time being, I think a direct port of the code from J2EE 1.4
> > to EE5 standards is essential, without changing any of the
> > fundamental business logic. From a performance standpoint, this
> > would provide the best measure of how well an EE5 application
> > stacks up against it's 1.4 counterpart.
> >
> > In this EE5 version I foresee 3 modes of operation...
> >
> > - Direct (JDBC)
> > - Session Direct (EJB3 Session to JDBC)
> > - Full EJB (EJB3 Session to EJB3 Entities)
> >
> > Nevertheless, I was wondering if an additional JPA mode would be of
> > interest? Based on my understanding of the relationship between JPA
> > and EJB3, the separating factor between the two is the scope of the
> > EntityManager (either application-based or container-based).
> > Consequently, would some form of JPA mode (using an application-
> > based EntityManager) provide a useful comparison?
>
> I can think of 3 more JPA modes:
>
> 1. App managed JPA from ejb3
> 2. container managed JPA from web (using UserTransaction for
> transaction demarcation)
> 3. App managed JPA from web.
>
> I'd be mostly interested in (2) but that doesn't mean it's most
> important or interesting for anyone else.
>
> thanks for working on this!
>
> david jencks
>
> >
> > Looking a little farther down the road, here are a few other things
> > I see on the horizon...
> >
> > - Java6 and JDBC 4.0 (How will this impact direct mode?)
> > - At some point, some wholesale changes to the business objects and
> > model should be made to place more demand on the application server
> > and not the database. These changes should also reflect the latest
> > trends in Web 2.0 application development practices. The AJAX/Dojo-
> > based interface that was recently added is a start; however, I feel
> > that more effort is needed here.
> >
> > I guess that's all for now... Let's see where this leads us...
> > Questions, thoughts, comments or snide remarks?
> >
> > Chris
> >
> >
> >
> > --
> > "I say never be complete, I say stop being perfect, I say let...
> > lets evolve, let the chips fall where they may." - Tyler Durden
>
>


-- 
"I say never be complete, I say stop being perfect, I say let... lets
evolve, let the chips fall where they may." - Tyler Durden

Mime
View raw message