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[javaee-spec users] [jsr342-experts] Re: custom injection annotations

  • From: Werner Keil <werner.keil@...>
  • To: jsr342-experts@...
  • Subject: [javaee-spec users] [jsr342-experts] Re: custom injection annotations
  • Date: Tue, 6 Nov 2012 11:11:33 +0100
  • List-id: <jsr342-experts.javaee-spec.java.net>

Bill/all,

I prefer @Inject, and please keep in mind, that annotation may be used by CDI, and given Bob Lee is too busy with his work at Square to drive any changes, everything in the Dependency Injection space still moving at JCP happens via CDI, e.g. DeltaSpike, but to use @Inject you do not depend the full CDI, only a handful of annotations that are JSR-330

We are having this discussion in the Agorava Project, and already have plans for Desktop/RCP or Mobile profiles or Agorava where CDI may be replaced by something else like Guice, etc. Same challenge here, but I would prefer to use 330/@Inject where it makes sense over a fragmentation and forking of such annotations.

Regards,
-- 

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On Tue, Nov 6, 2012 at 10:02 AM, Florent BENOIT <Florent.Benoit@...> wrote:
I agree with Antonio, it easier for people that want to inject something to always use @Inject instead of trying to remember which annotation needs to be used for each particular case.

For using some specs outside of Java EE, they can still use the dependency on CDI.


Regards,

Florent


On Tue, Nov 6, 2012 at 9:53 AM, Antonio Goncalves <antonio.goncalves@...> wrote:
Hi all,

I am the opposite of Markus on this one. I don't what to ask myself too many questions : need to inject a persistence context ? @Inject PersistenceContext. Need to inject an EJB ? @Inject MyEJB... and so on. I'm already disappointed to see @Context in JAX-RS. The programming model should be as easy as possible.

Then comes the "I don't want to depend on CDI". This to me sounds a bit strange. CDI 1.1 is standardizing bootstrapping in Java SE, so what's the issue ? If the Batch JSR needs CDI outside EE it just bootstraps CDI in Java SE. Then, depending on CDI only really means depending on another external jar (piece of cake for Maven)

I would like to see less custom technical annotations (let's use @Inject when we can) and in favour of more business annotation that developers can create (thanks to Stereotypes and Qualifiers)

Antonio


On Tue, Nov 6, 2012 at 6:48 AM, Markus Eisele <myfear@web.de> wrote:
Hi Bill/All,

Still very much split myself. I'm in favor of CDI. I simply don't like to see @Inject all over the place.
We already have a ton of custom annotations (e.g. @EJB) and if we treat them as a legacy artifact only we will probably end up with a programming model that needs good naming conventions (again) to be helpful.

@Inject
private MyBoundary boundaryEJB;

@Inject 
private JobContext batchContext;

This moves the problem to the user but should be solved in the platform. Having custom injection annotations makes this more readable and easier to follow in the code (at least for me).

I would like to see the expansion of use of CDI stereotypes (aka meta-annotations / stacked stereotypes) and require every EE spec to provide a CDI based injection annotation.
They should be free to provide additional ways for supporting standalone environments (e.g. via additional @Qualifiers).

- M


On 6 November 2012 01:10, Bill Shannon <bill.shannon@...> wrote:
I'd like to follow up on an issue we raised at the Java EE 7 BOF
about the use of custom injection annotations.

For example, should the Batch spec define

        @BatchContext
        private JobContext ctx;

or should it use

        @Inject
        private JobContext ctx;

The former is effectively a custom injection annotation unrelated to CDI.

The latter introduces a dependency on CDI.


In your opinion, which is preferred?  It seemed that the EE 7 BOF audience was
pretty evenly split on this one, and I can see arguments for either position.

If @Inject is preferred, should we allow custom annotations at the discretion
of the spec author, or should we disallow custom annotations entirely?

If custom injection annotations are allowed, should CDI make it easy to
define them, e.g., using something like:

@Stereotype
@Inject
public @interface BatchContext { }

If CDI supported this easily, applications could even define their own
injection annotations.

Should custom injection annotations be a legacy artifact that we need
to continue to support, or should we recognize it as a part of the
Java EE programming model and use it widely?




--
Antonio Goncalves
Software architect and Java Champion

Web site | TwitterLinkedInParis JUG | Devoxx France





[javaee-spec users] [jsr342-experts] custom injection annotations

Bill Shannon 11/06/2012

[javaee-spec users] [jsr342-experts] Re: custom injection annotations

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[javaee-spec users] [jsr342-experts] Re: custom injection annotations

Bill Shannon 11/06/2012

[javaee-spec users] [jsr342-experts] Re: custom injection annotations

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[javaee-spec users] [jsr342-experts] Re: custom injection annotations

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[javaee-spec users] [jsr342-experts] Re: custom injection annotations

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[javaee-spec users] [jsr342-experts] Re: custom injection annotations

Werner Keil 11/06/2012

[javaee-spec users] [jsr342-experts] Re: Re: custom injection annotations

Yoon Kyung Koo 11/06/2012

[javaee-spec users] [jsr342-experts] Re: custom injection annotations

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[javaee-spec users] [jsr342-experts] Re: custom injection annotations

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[javaee-spec users] [jsr342-experts] Re: custom injection annotations

Werner Keil 11/06/2012

[javaee-spec users] [jsr342-experts] Re: custom injection annotations

Antonio Goncalves 11/06/2012

[javaee-spec users] [jsr342-experts] Re: custom injection annotations

Werner Keil 11/06/2012

[javaee-spec users] Re: [jsr342-experts] Re: custom injection annotations

Nigel Deakin 11/07/2012

[javaee-spec users] Re: [jsr342-experts] Re: custom injection annotations

Antonio Goncalves 11/07/2012

[javaee-spec users] Re: [jsr342-experts] Re: custom injection annotations

Nigel Deakin 11/08/2012
 
 
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