Most of the JSF listener tags supports 'bind' attribute that allows to
use any JSF beans as listeners, that could have any scope and where
injection library could make any necessary work.
Because narrow listener objects are saved in the components tree, in
addition to the injection we should also define some addition lifecycle
methods ( e.g. activate/passivate ), otherwise status of injected
objects will be unpredictable. I suggest to check only is all listener
could be defined as binding to the JSF beans.
On 07/22/2009 06:54 AM, Dan Allen wrote:
On Wed, Jul 22, 2009 at 9:11 AM, Steve Roy
<steveroy(a)ensighttech.com
<mailto:steveroy@ensighttech.com>> wrote:
It would be nice if the design made it easy for resources to be
released when the beforePhase/afterPhase processing completes so
developers don't inadvertently forget to release expensive resources.
I can see the need for the feature. There is a danger though, that
it makes it too easy for developers to implement time & resource
expensive operations for invocations of the JSF lifecycle, which
should be considered time sensitive.
My focus was not necessarily on hooks to cleanup expensive resources.
To clarify, my focus is to get listeners to tie in better with the EE
platform. For instance, if I am developing an extension to JSF, and I
want to manipulate the JSR-299 conversation or perhaps wrap one or
more phases in a UserTransaction, there is no portable way to inject
the necessary components. Another use case is that I want to store
state in a JSR-299 contextual object or a stateful EJB session bean
(or a hybrid of the two). Again, no portable way to access this bean.
What I am looking for are injections like the following:
@Resource UserTransaction transaction;
@Current Conversation conversation;
@EJB Cart cart;
@Current StatusMessages statusMessages;
Right now phase and system event listeners have to use JNDI to get at
any of those resources, with subsequent calls necessary in some cases
(such as to get a contextual instance from the BeanManager).
My point is that managed objects in the Java EE platform should be
able to receive injections. I see phase listeners and system event
listeners as managed objects.
-Dan
--
Dan Allen
Senior Software Engineer, Red Hat | Author of Seam in Action
Registered Linux User #231597
http://mojavelinux.com
http://mojavelinux.com/seaminaction
http://in.relation.to/Bloggers/Dan