[webbeans-dev] Re: Redefinition of @New / clarification of injection for non-contextual instances

It gets better. If you declare <New/> as the binding for a bean defined in XML, you can override the injection metadata for non-contextual instances. Excellent! OK, I'm wrong about this solution being non-satisfying. It's completely satisfying. On Wed, Jan 14, 2009 at 11:43 PM, Gavin King <gavin(a)hibernate.org&gt; wrote: > There's one important thing that is not especially well-defined in the > spec today and that has been bothering me for a while. It's to do with > injection into non-contextual bean instances. > > There are a couple of cases where the spec supports injection into > non-contextual bean instances: > > * session beans obtained using JNDI lookup or direct injection using @EJB > * @New > > In each of these cases you get an instance of a bean which is *not* > bound to the scope declared by the bean. However, the spec still > requires injection into the bean instance. > > However, there may be multiple "beans" (i.e. instances of Bean) of the > given type: > > * one defined using only annotations > * others defined using XML > > and each "bean" may have different dependencies defined. > > So the question naturally arises: when I obtain this instance from > JNDI or using @New or @EJB, exactly *which* "bean" is it an instance > of? i.e. which set of bean metadata should be used? > > I've not found any completely satisfying answer to this question - but > there's only one possibility that is truly well-defined: > > * it is the one defined using annotations ... even if that bean has a > disabled deployment type! > > I've been thinking about how best to characterize this in the spec, > and I think the answer is slightly surprising. > > We should say that for each bean type, there is one extra "bean", so > we now have: > > * the one defined using only annotations > * one that is exactly the same, but with scope @Dependent, binding > @New and deployment type @Standard > * the others defined using XML > > We can now characterize session beans obtained using JNDI lookup or > @EJB as instances of the bean with binding @New, removing the > ambiguity. > > This approach lets me eliminate section 3.10 (yay!), since there is no > longer anything special/magical about @New, and replace it with some > shorter notes in 3.2/3.3. > > Even better, you'll no longer have to use the concrete type of the > bean when you inject using @New. This is especially useful for session > beans with no bean class local view. > > So this turns out to be simultaneously a simplification, enhancement > and clarification of the spec, and it's also easier to implement! > > Does that make sense to everybody? > > Anyway, I guess I will write this up so you guys can see what it looks > like in the spec. > > > -- > Gavin King > gavin.king(a)gmail.com > http://in.relation.to/Bloggers/Gavin > http://hibernate.org > http://seamframework.org > -- Gavin King gavin.king(a)gmail.com http://in.relation.to/Bloggers/Gavin http://hibernate.org http://seamframework.org