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 17:06:05 +0200

Pete, what would that mean for the following example ? This is the way you
inject UriInfo with JAX-RS :


@Path("/resource")public class Resource {
    *_at_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 {
    *_at_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
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