HI Dain, thanks for reviewing. Yes, you're right--I am scanning all the
classes in the web module for annotations, which might be excessive. I'll
take a look at the OpenEJB AnnotationDeployer and DeploymentLoader classes
tomorrow and see if I can discern the technique you mention (and then try
to emulate it). If I have questions, which is likely, I'll ask. Thanks much
Dain Sundstrom wrote:
Are you sure you must scan all classes in the web module for @EJB
annotations? I don't think it is necessary or what you want to do. I
believe that you should only be checking specific classes for the
annotation such as all known servlets. This is how we process
annotations for EJBs. First we find all EJBs, either listed in the
ejb-jar.xml or found by scanning for @Stateless, @Stateful and
@MessageDriven. Once we have the list of EJBs we check each class for
the presence of the @EJB annotation.
In your case, I believe you are scanning for all classes that have the
@EJB annotation which will be a much larger number of classes then just
the servlets. This over processing of classes can easily lead to naming
conflicts. Also, I do not believe that servlet 2.5 has an @Servlet
annotation, so I don't think you have to do any general purpose scanning
like EJB module must do, which should make web deployment much more
efficient.
Other than that, the patches look good :) One minor thing to note is we
don't use prefixes such as "m_" for variables.
Good job,
-dain
On Feb 10, 2007, at 1:23 AM, Tim McConnell wrote:
Hi, I've attached a patch and two new classes to the GERONIMO-2816
JIRA that provides support for the @EJB and @EJBs
annotations if anyone would like to review. The intent is to
demonstrate a final/permanent technique that can be extended and used
throughout Geronimo to support annotations for JSR-88. This patch and
new code works for Tomcat and circumvents the annotation processing
that is currently in EjbRefBuilder (which did not update the
deployment descriptor with the discovered annotations, but only
updated the JNDI references). I'd appreciate some feedback before I
start propagating this technique to the other module builders to
support the remainder of the annotations. I already have another
subclass ready to support the @Resource annotations but I didn't want
to include it in this example since it doesn't demonstrate anything
different than the EJBAnnotationHelper subclass, and I'd like to get
some feedback first on the the technique. The general technique, which
we've discussed before, is pretty straightforward and is summarized
here for reference:
1 -- Discover the annotations: I had hoped that we could centralize
the discovery of annotations in the Deployer class prior to the
createModule phase of deployment, but as David Blevins pointed out
this is almost impossible. So it has to be pushed down into the
installModule phase of deployment after the necessary classloader(s)
and module context(s) have been established (see the changes for
AbstractWebModuleBuilder for an example).
2 -- Process the annotations: This just means to update the existing
deployment descriptor (or create a new one) with the discovered
annotations.
3 -- Set metadata-complete in the deployment descriptor to prevent
repeated processing of annotations (see the EjbRefBuilder changes for
an example)
4 -- Update the deployment descriptor in the module so that it can
flow through the remainder of the deployment process much as before
(for JNDI naming and resolution, and to remain with module in support
of the JSR-77 requirements for management).
--
Thanks,
Tim McConnell
--
Thanks,
Tim McConnell
