On the concall, we made some significant progress with the design for hierarchical Managers. We decided to develop the following approach: (1) web beans belonging to a child manager may have any scope (2) each child manager has its own set of contexts (there is a parallel context hierarchy for each scope) that "belong" to, and have the same lifecycle as, the parent contexts (3) therefore the web beans belonging to the child are not visible to web beans belonging to the parent (4) however, web beans belonging to the parent *are* visible to web beans belonging to the child (5) a child manager may be associated with a context by calling Manager.setCurrent(ScopeType), and is then automagically propagated with the context (6) web beans belonging to the child manager may be obtained via EL evaluation whenever the child manager is in scope, or by directly calling a getInstance() method of the child manager The needed API changes are as follows: Manager { public Manager createChild(); public void setCurrent(Class<? extends Annotation> scope); public void validate(); } Context { getChild(Manager childManager); } There is one question remaining open: Should it *ever* be possible to access a web bean belonging to the child manager via a reference that was injected into a web bean belonging to the parent manager or into some non-contextual object such as a servlet or MDB? For example, we might choose to support this in the case that the child manager web bean specializes the parent manager web bean. Bill, is this a feature that Oracle requires? If not, I'm inclined to *not* support it in web beans 1.0. -- Gavin King gavin.king(a)gmail.com http://in.relation.to/Bloggers/Gavin http://hibernate.org http://seamframework.org

OK, here's a first draft of the definition of child managers, assuming the simpler solution (1). Please take a look at sections 11.7 and 11.2 and let me know your feedback. On Thu, Dec 4, 2008 at 1:19 PM, Gavin King <gavin(a)hibernate.org&gt; wrote: > I've discovered a problem with setCurrent(scopeType). > > What if I called: > > child1.setCurrent(BusinessProcessScoped.class) > child2.setCurrent(SessionScoped.class) > > Then I would have an ambiguity about "which" current manager was > intended, since there is no definable ordering between these to > scopes. > > There's two possible solutions to this: > > (1) Limit setCurrent() to the request scope, and require that the > orchestration framework take care of propagation to other requests. > (2) Say that if 2 different current contexts have different child > managers defined, an exception is thrown > > Which option do you think we should go for? > > On Thu, Nov 27, 2008 at 4:30 PM, Gavin King <gavin(a)hibernate.org&gt; wrote: >> On the concall, we made some significant progress with the design for >> hierarchical Managers. We decided to develop the following approach: >> >> (1) web beans belonging to a child manager may have any scope >> (2) each child manager has its own set of contexts (there is a >> parallel context hierarchy for each scope) that "belong" to, and have >> the same lifecycle as, the parent contexts >> (3) therefore the web beans belonging to the child are not visible to >> web beans belonging to the parent >> (4) however, web beans belonging to the parent *are* visible to web >> beans belonging to the child >> (5) a child manager may be associated with a context by calling >> Manager.setCurrent(ScopeType), and is then automagically propagated >> with the context >> (6) web beans belonging to the child manager may be obtained via EL >> evaluation whenever the child manager is in scope, or by directly >> calling a getInstance() method of the child manager >> >> The needed API changes are as follows: >> >> Manager { >> public Manager createChild(); >> public void setCurrent(Class<? extends Annotation> scope); >> public void validate(); >> } >> >> Context { >> getChild(Manager childManager); >> } >> >> There is one question remaining open: >> >> Should it *ever* be possible to access a web bean belonging to the >> child manager via a reference that was injected into a web bean >> belonging to the parent manager or into some non-contextual object >> such as a servlet or MDB? >> >> For example, we might choose to support this in the case that the >> child manager web bean specializes the parent manager web bean. >> >> Bill, is this a feature that Oracle requires? If not, I'm inclined to >> *not* support it in web beans 1.0. >> >> -- >> 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 > -- Gavin King gavin.king(a)gmail.com http://in.relation.to/Bloggers/Gavin http://hibernate.org http://seamframework.org