[cdi-dev] [weld-dev] Question about the spec for BeanManager.getBeans
Emily Jiang
EMIJIANG at uk.ibm.com
Tue Aug 28 14:37:31 EDT 2018
Thank you Martin!
I think the ticket you referred is clearer spelt out that all beans are
included included disabled ones. From what you mentioned here, OWB based
on Ben's experiment is incorrect by filtering out the disabled beans when
calling beanmanager.getBeans().
Many thanks,
Emily
===========================
Emily Jiang
WebSphere Application Server, Liberty Architect for MicroProfile and CDI
MP 211, DE3A20, Winchester, Hampshire, England, SO21 2JN
Phone: +44 (0)1962 816278 Internal: 246278
Email: emijiang at uk.ibm.com
Lotus Notes: Emily Jiang/UK/IBM at IBMGB
From: Martin Kouba <mkouba at redhat.com>
To: Emily Jiang <EMIJIANG at uk.ibm.com>, Matej Novotny
<manovotn at redhat.com>, cdi-dev <cdi-dev at lists.jboss.org>
Cc: Benjamin Confino <BENJAMIC at uk.ibm.com>, weld-dev at lists.jboss.org
Date: 27/08/2018 08:51
Subject: Re: [cdi-dev] [weld-dev] Question about the spec for
BeanManager.getBeans
Hi all,
BeanManager#getBeans() should not apply ambiguous dependency resolution
rules - see also CDI-231 [1] and related changes. These rules should
only be applied by BeanManager#resolve().
BeanManager#getBeans() and BeanManager#resolve() are in fact even more
complicated because they should honor the inter-module injection rules.
In other words, it also depends where you request the beans from. And
this is where Weld and OWB differ a lot.
Martin
[1]
https://issues.jboss.org/browse/CDI-231
Dne 24.8.2018 v 23:08 Emily Jiang napsal(a):
> Matej,
>
> Thanks for your quick reply!
> I think the spec is quite clear by saying the candidates of typesafe
> resolutions defined in Performing typesafe resolutions... surely a
> disabled bean cannot be a candidate. it is simply disquailified.
>
> It did not say eliminate all beans but one though. I think it should be
> eliminate disqualified ones and leave all qualified at least.
>
> I am sending to cdi-dev for clarification. Antoine, please comment.
>
> Many thanks,
> Emily
> ===========================
> Emily Jiang
> WebSphere Application Server, Liberty Architect for MicroProfile and CDI
>
> MP 211, DE3A20, Winchester, Hampshire, England, SO21 2JN
> Phone: +44 (0)1962 816278 Internal: 246278
>
> Email: emijiang at uk.ibm.com
> Lotus Notes: Emily Jiang/UK/IBM at IBMGB
>
>
>
>
> From: Matej Novotny <manovotn at redhat.com>
> To: Benjamin Confino <BENJAMIC at uk.ibm.com>
> Cc: weld-dev at lists.jboss.org, Emily Jiang <EMIJIANG at uk.ibm.com>
> Date: 24/08/2018 16:17
> Subject: Re: [weld-dev] Question about the spec for BeanManager.getBeans
> ------------------------------------------------------------------------
>
>
>
> Hi
>
> Looking at spec 11.3.6. Obtaining a Bean by type[1] I can see that the
> paragraph ends with "according to the rules for candidates of typesafe
> resolution defined in Performing typesafe resolution.".
> The important word here is *candidates* IMO.
> The way typesafe resolution is defined, both the original bean and the
> alternatives are candidates. According to spec, the original bean is
> still considered enabled[2]
> Note that CDI spec doesn't say that @Alternative would completely
> eliminate the original bean, it just takes precedence during resolution
> (as opposed to what specialization does[3]).
>
> Last but not least, one thought - if the getBeans() method was to
> perform a typesafe resolution and eliminate all but one bean - why would
> it return a Set (and not throw unsatisfied/ambiguous exceptions)? :)
>
> Matej
>
______________________________________________________________________________
> [1]
http://docs.jboss.org/cdi/spec/1.2/cdi-spec.html#bm_obtain_bean_by_type
> [2]
http://docs.jboss.org/cdi/spec/1.2/cdi-spec.html#enablement
> [3]
http://docs.jboss.org/cdi/spec/1.2/cdi-spec.html#specialization
>
>
> ----- Original Message -----
> > From: "Benjamin Confino" <BENJAMIC at uk.ibm.com>
> > To: weld-dev at lists.jboss.org
> > Cc: "Emily Jiang" <EMIJIANG at uk.ibm.com>
> > Sent: Friday, August 24, 2018 3:10:05 PM
> > Subject: [weld-dev] Question about the spec for BeanManager.getBeans
> >
> > Hello
> >
> > I was made aware of the difference on the return of
> > beanManager.getBeans(Object.class) between OWB and Weld
> >
> > In OWB, it returns all beans, unless there is an enabled @alternative
> within
> > the application. If there is an enabled @alternative getBeans() only
> returns
> > beans annotated @alternative.
> >
> > However, in Weld, it returns all beans even with an enabled
@alternative.
> >
> > The JavaDoc for BeanMnanager says "according to the rules of typesafe
> > resolution" and in the CDI 1.0 spec under typesafe resolution I find
one
> > mention of alternatives: “When an ambiguous dependency exists, the
> container
> > attempts to resolve the ambiguity. The container eliminates all
eligible
> > beans that are not alternatives, except for producer methods and
> fields of
> > beans that are alternatives.” (This text is also in the CDI 1.2 spec)
> >
> > However this would imply that if there are no enabled @Alternatives
an
> > ambiguous resolution like beanManager.getBeans(Object.class) should
> discard
> > everything. In this case, the Weld behaviour is incorrect.
> > beanManager.getBeans() should only return the resolved or enabled
beans.
> >
> > Regards
> > Benjamin
> >
> > Can someone verify this?
> > Unless stated otherwise above:
> > IBM United Kingdom Limited - Registered in England and Wales with
number
> > 741598.
> > Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire
> PO6 3AU
> >
> > _______________________________________________
> > weld-dev mailing list
> > weld-dev at lists.jboss.org
> >
https://lists.jboss.org/mailman/listinfo/weld-dev
>
>
>
>
> Unless stated otherwise above:
> IBM United Kingdom Limited - Registered in England and Wales with number
> 741598.
> Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6
3AU
>
>
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--
Martin Kouba
Senior Software Engineer
Red Hat, Czech Republic
Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number
741598.
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU
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