Re: [webbeans-dev] Re: Stereotype inheritance proposal

On 21 Nov 2008, at 18:07, Gavin King wrote: > oops forgot to attach the spec > > On Fri, Nov 21, 2008 at 1:05 PM, Gavin King <gavin(a)hibernate.org&gt; > wrote: >> I've got feedback from a number of people that stereotype >> inheritance >> should be supported, and I agree with this feedback. I can't see a reason not to support it, except that stereotypes are already very powerful, so without seeing use cases for which stereotype inheritance is considerably simpler, I would say it's a nice-to-have only. >> >> >> I think we should just do it in the simplest possible way and say >> simply that stereotype declarations are transitive, and >> meta-stereotypes are inherited by the web bean. >> >> Therefore: >> >> 1. the sets of interceptor binding types are unioned >> 2. any conflicts between default scope/deployment type defined by a >> stereotype and its meta-stereotypes must be resolved by explicit >> declaration on the web bean >> 3. all restrictions apply cumulatively >> >> And I've written this into section 2.7.1.5 of the attached spec >> draft. >> >> Questions: >> ======== >> >> Does anybody think that the default scope/deployment type declared >> directly by a stereotype should *override* the default >> scopes/deployment types declared by its meta-stereotypes? This rule >> makes a lot of sense, but it kinda makes things a little more >> complex. >> >> For example: >> >> @RequestScoped >> @Stereotype >> public @interface Foo {} >> >> @SessionScoped >> @Foo >> @Stereotype >> public @interface Bar {} >> >> Should we force a web bean that declares @Bar to explicitly >> specify a >> scope, or is it better to let @SessionScoped on Bar override >> @RequestScoped on Foo. I agree, it makes more sense for the stereotype to override the meta- stereotype. >> >> >> >> Another thing I've just noticed, that applies to interceptor >> bindings >> inherited by both stereotypes and other interceptor binding types, >> is >> that you could potentially have a web bean with multiple "instances" >> of the same interceptor binding type - the same type, but different >> member values. I think we should say that this is a >> DefinitionException. >> >> For example: >> >> @Transactional(requiresNew=false) >> @Stereotype >> public @interface Foo {} >> >> @Transactional(requiresNew=true) >> @Stereotype >> public @interface Foo {} >> >> @Foo @Bar >> public class X {} >> >> Then X has both @Transactional(requiresNew=false) and >> @Transactional(requiresNew=true). >> >> >> -- >> 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 > <Web Beans > 20081121.pdf>_______________________________________________ > webbeans-dev mailing list > webbeans-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/webbeans-dev