Sorry if I'm behind on this discussion but what are the current
thoughts on how dependency injection will be implemented for managed
beans?  The reason I'm curious is because PreDestroy and PostConstruct
annotations are used to deal with injected resources, so from a timing
perspective it would be important to process all these annotations
accordingly.

Best wishes,
Paul

On 2/24/07, Dennis Byrne <[EMAIL PROTECTED]> wrote:
I'm weighing options about invoking @PreDestroy methods (@PostConstruct is
done BTW).  I haven't made up my mind yet but here's where I'm at on this.

As far as *when* this happens, the request is easy, in
FacesServelet.service(). Session and app scope are more difficult decisions.
A new HttpSessionActivationListener.attributeRemoved and a
new ServletContextAttributeListener.attributeRemoved() seem
like nice solutions, but this doesn't meet the spec requirements for 5.4.1.
The methods have to be invoked *before* the bean is pulled from scope and
the servlet API does not provide a
ServletContextAttributeListener.attribute_WILL_BE_Removed()
or a
HttpSessionActivationListener.attribute_WILL_BE_Removed ().
 Also, I say *new* ServletContextAttributeListener and because
StartupServletContextListener (already in code base) implements
ServletContextListener, not
ServletContextAttributeListener.

The other side of the problem is *how* to invoke each @PreDestroy method,
much easier.  Iterating over the attributes at each scope level is trivial,
and so is determining if the bean's class is a managed bean class. But this
does not mean the *instance* was placed there by the JSF implementation.
Using a list (at each level of scope) to track managed instances solves the
problem, as long as you sync on the session (only one time per session) in
order to avoid concurrency issues; it also means three more data structures
in memory.

--
Dennis Byrne

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