The RI looks for "com.sun.faces.spi.InjectionProvider" for a class
name which implements this interface. It would have been very nice if
this is part of the spec. But that is not the case so we need to find
a way to support any kind of j2ee container. IMO injecting j2ee
resources without knowing where these resources can be found is not
possible. Therefore myfaces should call an InjectionProvider which
simply do this job.

2007/3/3, Dennis Byrne <[EMAIL PROTECTED]>:
Are any of these class names or context params start w/ javax.faces ?  If
so, we can move the conversation back into the issue tracker and I'll close
the @PostConstruct issue once Paul says it's good to go.  I don't see the
point of the system property though.

Dennis Byrne


On 3/2/07, Mathias Brökelmann <[EMAIL PROTECTED]> wrote:
> The RI uses two ways to lookup the implementation of the vendor
> specific implementation of the InjectionProvider. They first try to
> use a web context init param and if that is not configured they simply
> use a system property. Both keyed by the class name of the
> InjectionProvider interface.
>
> 2007/3/2, Paul McMahan <[EMAIL PROTECTED]>:
> > I think Mathias' suggestion is right on.  I haven't looked at the RI
> > code but I read somewhere that it passes the name of
> > InjectionProviders via entries in META-INF/services.  If MyFaces used
> > a similar approach I think it should work OK for Geronimo and just
> > about any other container that supports injection,  And it should also
> > make MyFaces more interchangeable with the RI.
> >
> > Best wishes,
> > Paul
> >
> > On 3/2/07, Dennis Byrne <[EMAIL PROTECTED]> wrote:
> > > Similar to what Mathias mentioned?
> > >
> > >
http://issues.apache.org/jira/browse/MYFACES-1246#action_12475337
> > >
> > > It's not much work (on our side) but it sounds pretty vendor specific.
> > > Again, I don't have a better solution.  Mathias writes "which is
implemented
> > > by j2ee containers".  I wonder if each container will end up looking
for
> > > different interfaces.  How would MyFaces find Geronimo's
implementation ?  A
> > > context parameter?  A for loop like this ...
> > >
> > > String[] providers = new String[]{"org,apache.geronimo.DIProvider",
> > > "com.bea.DIProvider", "org.jboss.DIProvider "}
> > >
> > > for(String clazz : providers){
> > >   try{
> > >     return ClassUtils.load (clazz)
> > >   }catch(){}
> > > }
> > >
> > > Dennis Byrne
> > >
> > >
> > > On 3/1/07, Paul McMahan <[EMAIL PROTECTED]> wrote:
> > > > OK, I think your interpretation of the spec makes sense and there's
> > > > one particular aspect we should discuss a little further.
> > > >
> > > > The container doesn't know which classes are managed beans so it
> > > > wouldn't know when to intercept the instantiation process to perform
> > > > injection.  What would you all think about MyFaces providing an
> > > > interface that containers could implement to perform injection on a
> > > > managed bean when MyFaces brings that bean into service?  This would
> > > > allow MyFaces to maintain control of the timing while allowing the
> > > > container to scan for annotations and handle injection when prompted
> > > > to do so.
> > > >
> > > > Best wishes,
> > > > Paul
> > > >
> > > >
> > > > On 2/26/07, Dennis Byrne <[EMAIL PROTECTED]> wrote:
> > > > > I know the specs can be vague sometimes, but I don't interpret the
first
> > > > > paragraph of section 5.4 as meaning the JSF implementation is
> > > responsible
> > > > > for @EJB, @Resources, etc.  The JSF spec specifically mentions
"the
> > > > > container to inject references".  If Geronimo can intercept the
> > > > > instantiation of these classes in the classloader (something I
know
> > > nothing
> > > > > about right now), I think we are all good here.  Wouldn't MyFaces
then
> > > be
> > > > > observing the requirements (in plain java) around @PostConstruct
after
> > > > > Geronimo had injected the resources?
> > > > >
> > > > > I think the JSF impl is only responsible for @PostConstruct and
> > > @Predestroy.
> > > > >  This makes sense because scoped (request, session, application)
are the
> > > > > only candidates for this, and it would be more awkward to do that
from
> > > the
> > > > > container. I say all of this in an open manner, so anyone feel
free to
> > > > > discuss.
> > > > >
> > > > > You're point about javax.annotation being in the Servlet 2.5 is
taken.
> > > I
> > > > > totally missed that.
> > > > >
> > > > >
> > > > > Dennis Byrne
> > > > >
> > > > > On 2/26/07, Paul McMahan < [EMAIL PROTECTED]> wrote:
> > > > > > Actually by "dependency injection" I'm specifically referring to
the
> > > > > > portion of the JSF spec that discusses injecting resources where
> > > > > > certain annotations are found in a managed bean.  So, while
scanning
> > > > > > for the @PreConstruct and @PostDestroy annotations MyFaces would
also
> > > > > > scan for @EJB, @Resource, @WebServiceRef, etc and then time the
> > > > > > invocation of @PreConstruct and @PostDestroy to support the
injection.
> > > > > >
> > > > > > Tomcat provides an example of how this can be done.  The
following
> > > > > > class scans for annotations when a web app starts:
> > > > > >
> > > > >
> > >
http://svn.apache.org/repos/asf/tomcat/tc6.0.x/trunk/java/org/apache/catalina/startup/WebAnnotationSet.java
> > > > > >
> > > > > > And then this class handles the injection and calling the
> > > > > > PostConstruct and PreDestroy methods when an servlet, filter, or
> > > > > > listener is brought into service:
> > > > > >
> > > > >
> > >
http://svn.apache.org/repos/asf/tomcat/tc6.0.x/trunk/java/org/apache/catalina/util/DefaultAnnotationProcessor.java
> > > > > >
> > > > > > Would it make sense for MyFaces to follow a similar approach for
> > > > > > managed beans?  Also, I'm curious why you're hoping to avoid
importing
> > > > > > classes from javax.annotation classes since servlet 2.5
containers are
> > > > > > required to support them.  Is this so that MyFaces 1.2 can
support
> > > > > > servlet 2.4 containers?
> > > > > >
> > > > > > Best wishes,
> > > > > > Paul
> > > > > >
> > > > > > On 2/26/07, Dennis Byrne < [EMAIL PROTECTED]> wrote:
> > > > > > > I ended up going with Servlet/Request/Context attribute
listeners
> > > for
> > > > > > > @PreDestroy.  This did not involve importing
> > > > > javax.annotation.PreDestroy, so
> > > > > > > people w/out application servers don't have to worry about
> > > > > > > ClassDefNotFoundErrors.  This also keeps us compatible with
the
> > > > > reference
> > > > > > > implementation in terms of timing, although I really wish
they'd
> > > change
> > > > > the
> > > > > > > wording in the spec.
> > > > > > >
> > > > > > > Dennis Byrne
> > > > > > >
> > > > > > >
> > > > > > > On 2/26/07, Paul McMahan < [EMAIL PROTECTED]> wrote:
> > > > > > > > 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
> > > > > > > >
> > > > > > >
> > > > > > >
> > > > > > >
> > > > > > > --
> > > > > > > Dennis Byrne
> > > > > >
> > > > >
> > > > >
> > > > >
> > > > > --
> > > > > Dennis Byrne
> > > >
> > >
> > >
> > >
> > > --
> > > Dennis Byrne
> >
>
>
> --
> Mathias
>



--
Dennis Byrne


--
Mathias

Reply via email to