users@javaee-spec.java.net

[javaee-spec users] [jsr342-experts] Re: CDI positioning

From: Antonio Goncalves <antonio.goncalves_at_gmail.com>
Date: Fri, 31 Aug 2012 17:22:03 +0200

Well, that would be awesome, but is there anybody here who is part of
JAX-RS Expert Group and could tell us if it's doable or not ?

Same, do we know what the JSF 2.2 EG plans to do with @ManagedBean vs
@Named ?

On Fri, Aug 31, 2012 at 5:10 PM, Pete Muir <pmuir_at_bleepbleep.org.uk> wrote:

> Well, I think based on D, injection is something that CDI provides, and
> JAX-RS is fully functional without injection, so JAX-RS shouldn't provide
> @Context at all as it duplicates functionality from CDI.
>
> On 31 Aug 2012, at 16:06, Antonio Goncalves wrote:
>
> > Pete, what would that mean for the following example ? This is the way
> you inject UriInfo with JAX-RS :
> >
> >
> > @Path(
> > "/resource"
> > )
> >
> > public
> > class Resource {
> >
> > @Context
> >
> >
> > private UriInfo info;
> >
> >
> >
> >
> > Injection is made with @Context in a standalone mode without CDI. But in
> a Java EE container I would really like to use @Inject rather than @Context
> (so the code is not portable anymore without CDI) :
> >
> >
> > @Path(
> > "/resource"
> > )
> >
> > public
> > class Resource {
> >
> > @Inject
> >
> >
> > private UriInfo info;
> >
> >
> > Antonio
> > On Fri, Aug 31, 2012 at 4:55 PM, Pete Muir <pmuir_at_bleepbleep.org.uk>
> wrote:
> > Bill, et al
> >
> > We would like to propose a slight variant on option C:
> >
> > D. Technologies that can be standalone specifications (JMS, JAX-RS)
> should be fully functional without CDI, but they should not duplicate any
> features of CDI. When CDI is present, these technologies should leverage
> and integrate with CDI where appropriate.
> >
> > On 30 Aug 2012, at 21:58, Bill Shannon wrote:
> >
> > > From many of our recent discussions, it seems clear that CDI is
> > > becoming more central to the Java EE programming model. For example:
> > >
> > > - The expanded use of @Stereotype in my previous message.
> > >
> > > - The use of CDI interceptors to provide container managed
> > > transaction support beyond EJB.
> > >
> > > - The potential future use of CDI interceptors to provide container
> > > managed security support beyond EJB.
> > >
> > > - The use of CDI interceptors to support Bean Validation method
> > > level validation.
> > >
> > > - The discussion of "implicit producers" to allow use of @Inject
> > > instead of @Resource to inject Java EE resources.
> > >
> > > - The discussion around alignment of CDI managed beans and the
> > > separate @ManagedBean spec.
> > >
> > > - The introduction of a transaction scope and its use in the JMS
> > > spec to simplify the programming model.
> > >
> > > - The change being considered by the CDI expert group to enable
> > > CDI by default, making it more attractive to use it for all
> > > the items above.
> > >
> > >
> > > At the same time we're finding that some specs, e.g., JAX-RS, are
> > > hesitant to introduce a hard, or even soft, dependency on CDI,
> > > instead insisting that all their new features must work in an
> > > environment where there is no CDI.
> > >
> > > In many ways this parallels what we saw with annotations. In
> > > the beginning we found many people who didn't want to use annotations
> > > and wanted us to make sure everything worked without use of
> > > annotations. Now we're seeing many things that *only* work with
> > > annotations, and annotations are well accepted by Java EE developers.
> > > I suppose there's a natural lifecycle to acceptance of new
> > > technologies, and I wonder where we are in that lifecycle with CDI?
> > > Has CDI become a mature and accepted technology that we should use
> > > widely?
> > >
> > >
> > > I'd like to get a sense from this group as to what direction we
> > > should provide to all the Java EE specs in regards to their use
> > > of CDI. Here's a few obvious options:
> > >
> > > A. Technologies that see a significant standalone (non-Java EE) use
> > > should be fully functional without CDI. If necessary, any
> > > required features that are similar to CDI features should be
> > > defined and implemented in a way that doesn't depend on CDI.
> > >
> > > B. Technologies should provide all major features in a way that
> > > works without CDI. Some features may also be provided in a
> > > different way that works well with CDI. Some less essential
> > > features may only work with CDI. The implementation should
> > > only have a soft dependency on CDI at most.
> > >
> > > C. Technologies should provide features that work well with CDI
> > > without duplicating any functionality in CDI. Use CDI wherever
> > > it fits. The implementation may have a hard dependency on CDI
> > > and may require CDI even when used in a standalone environment.
> > >
> > > I'm sure you can think of other options as well.
> > >
> > > What advice do you think we should give to other Java EE specs?
> >
> >
> >
> >
> > --
> > Antonio Goncalves
> > Software architect and Java Champion
> >
> > Web site | Twitter | LinkedIn | Paris JUG | Devoxx France
>
>


-- 
Antonio Goncalves
Software architect and Java Champion
Web site <http://www.antoniogoncalves.org> |
Twitter<http://twitter.com/agoncal>|
LinkedIn <http://www.linkedin.com/in/agoncal> | Paris
JUG<http://www.parisjug.org> |
Devoxx France <http://www.devoxx.fr>