[webbeans-dev] Fwd: Patterns of reuse

So, after talking this over with Jason, we're inclined to think that we should rely on the use of the @Inherited annotation in java.lang.annotation to control inheritance of type-level metadata: * scope * deployment type * binding types * name * stereotypes * type-level interceptor bindings For annotations defined by the spec, we would say that: * all built-in scope types are declared @Inherited * no built-in binding type is declared @Inherited * @Name is not declared @Inherited * no built-in stereotype is declared @Inherited There are four scenarios of metadata inheritance in the spec today: * implementation class inheritance * XML configuration * stereotype transitivity * interceptor binding type transitivity I think @Inherited is definitely a good way of controlling metadata inheritance in the cases of implementation class inheritance and XML configuration. For example, if we have the following types: @MyStereotype class Foo { ... } class Bar extends Foo { .... } then it seems completely natural to me that we would decide whether @MyStereotype is inherited by Bar on the basis of whether it is declared @Inherited. Likewise, it seems natural in the case of XML configuration: <myapp:Foo> ... </myapp:Foo> The big question in my mind is whether it is also appropriate to use this mechanism to control transitivity of metadata declared by stereotypes, for example, suppose that @MyStereotype declares @MyOtherStereotype: @MyOtherStereotype @Stereotype ... public @interface MyStereotype { ... } And @MyOtherStereotype declares a deployment type: @Staging @Stereotype ... public @interface MyOtherStereotype { ... } Should we look at the @Inherited annotation to decide if @Staging is inherited by @MyStereotype? I'm thinking that the answer is "no", but I'm not sure. Of course, we still need to define "special" rules for the member-level metadata: * method-level interceptor bindings * initializer methods + injected fields * producer/disposal * observer methods Does all that make sense? -- Gavin King gavin.king(a)gmail.com http://in.relation.to/Bloggers/Gavin http://hibernate.org http://seamframework.org