I'm going to tread carefully when arguing this point because I am far from a
master at generics. Unfortunately, it seems that the non-normative section
of the generics documentation is not consistent with the generics API. For
instance, in the documentation, a type parameter is described as a special
kind of type variable. But in the generics API, they are two separate things
(ParameterizedType and TypeVariable). But I may be mistaken.
With that said, the example I gave fails in Web Beans. Let me give a full
example:
public class Artist<T> { ... }
public class Solo { ... }
public class TuneSelect {
@Any Event<Artist<Solo>> soloArtistEvent;
public void soloArtistPlaying(Artist<Solo> artist)
{
soloArtistEvent.fire(artist);
}
}
Here's the exception Web Beans spits out.
java.lang.IllegalArgumentException: Event type
org.jboss.jsr299.tck.tests.event.eventTypes.Artist is not allowed because it
is a generic
at
org.jboss.webbeans.BeanManagerImpl.fireEvent(BeanManagerImpl.java:798)
at org.jboss.webbeans.event.EventImpl.fire(EventImpl.java:76)
=> same result for soloArtistEvent.fire(new Artist<Solo>())
If you believe that should be valid, then I will simply mark it as
ri-broken.
I see what you are saying though in that what is not allowed is a type which
is tied to the method parameters, hence acting as a type variable.
-Dan
On Fri, Jul 24, 2009 at 12:46 PM, Pete Muir <pmuir(a)redhat.com> wrote:
No, the spec prohibits type variables in event objects and event
types, it
doesn't prohibit type parameters.
This isn't legal
public class Foo{
@Produces <T> Bar make(@Any Event<T> event) {
...
}
and we do need to error at deployment time for such a declaration. Do we?
What you show *is* valid.
It's also not valid to actually pass an event object with a type variable,
but it's extremely hard to actually find code that will compile and pass the
above deployment test, but still do this and do this so I can't find an
example right now ;-)
On 24 Jul 2009, at 17:28, Dan Allen wrote:
In several places, the specification reiterates that an event type may not
> contain a type variable. However, it appears that this restriction is only
> enforced at runtime when the event object is passed to either Event#fire()
> or BeanManager#fireEvent() method. I would suggest that an validation check
> be added so that the container detects an illegal Event definition at
> deployment type. Here's an example of an illegal definition (from my
> understanding):
>
> public class VoterRegistration<T> { ... }
>
> @Any Event<VoterRegistration<Democrat>> democratRegisteredEvent;
>
> -Dan
>
> --
> Dan Allen
> Senior Software Engineer, Red Hat | Author of Seam in Action
> Registered Linux User #231597
>
>
http://mojavelinux.com
>
http://mojavelinux.com/seaminaction
>
http://in.relation.to/Bloggers/Dan
> _______________________________________________
> webbeans-dev mailing list
> webbeans-dev(a)lists.jboss.org
>
https://lists.jboss.org/mailman/listinfo/webbeans-dev
>
--
Dan Allen
Senior Software Engineer, Red Hat | Author of Seam in Action
Registered Linux User #231597
http://mojavelinux.com
http://mojavelinux.com/seaminaction
http://in.relation.to/Bloggers/Dan