[webbeans-dev] Web Bean discovery

[Gavin King]

Let's chat on the phone about it.

On Thu, Dec 4, 2008 at 10:11 AM, Pete Muir <pmuir at redhat.com> wrote:
> Gavin,
>
> I need to better understand the use-cases we are trying to address here -
> I've been over this again, and there is no way I can see to build a flexible
> class discovery system that performs well without understanding what sort of
> conditions/restrictions we want to impose.
>
> So far, I have:
>
> * abstract classes
> * non-abstract classes (simple/enterprise beans)
> * annotations annotated with the some meta-annotations (e.g. stereotypes)
>
> What else?
>
> Pete
>
> On 26 Nov 2008, at 17:42, Gavin King wrote:
>
>> Right, it is important that any jboss-specific functionality is
>> abstracted.
>>
>> On Wed, Nov 26, 2008 at 7:45 AM, Pete Muir <pmuir at redhat.com> wrote:
>>>
>>> Ok - so we would need to wrap this ClassFilter in an equivalent Web Beans
>>> API I think, and then use Javassist as you suggest. Any idea how portable
>>> such an approach will be to other app servers?
>>>
>>> On 26 Nov 2008, at 18:29, Ales Justin wrote:
>>>
>>>> This is trivial to do in JBoss5. ;-)
>>>>
>>>>
>>>>
>>>> http://anonsvn.jboss.org/repos/jbossas/projects/webbeans-ri-int/trunk/microcontainer/src/main/java/org/jboss/webbeans/integration/microcontainer/WebBeanDiscoveryDeployer.java
>>>>
>>>> module.visit(visitor, ClassFilter.INSTANCE, null, urls.toArray(new
>>>> URL[urls.size()]));
>>>>
>>>> You only need to replace this ClassFilter parameter.
>>>> e.g. some Javassist based filter --> no need to load the class to
>>>> inspect
>>>> it
>>>>
>>>> You could then organize your 'store' accordingly to the filter.
>>>> e.g. CombinedFilter(modifier, type, ...) --> push to sub-store
>>>>
>>>> Pete Muir wrote:
>>>>>
>>>>> I was talking to Gavin about this, and he suggested that the discovery
>>>>> should be more flexible and allow selectors/restrictions to be applied
>>>>> to
>>>>> the classes discovered (for example, only abstract classes).
>>>>> I can only speak about JBoss5, but I suspect this approach is common -
>>>>> JBoss allows you to attach a visitor to the deployer and allows you to
>>>>> do
>>>>> something with classes it finds (e.g. store them in some data
>>>>> structure).
>>>>> This happens before web apps (from the Servlet listener) starts.
>>>>> The current approach is to discover the resources needed (as defined by
>>>>> the spec) and store them in a datastructure, which is available later
>>>>> for
>>>>> querying when we boot the Web Beans RI through the ServletListener. So,
>>>>> the
>>>>> only way I can see to be more flexible is to add the ability to apply
>>>>> selectors to the WebBeanDiscovery interface, and index the classes
>>>>> discovered based on selectors in the jboss-webbeans integration
>>>>> library.
>>>>> This requires us to define the selectors we can use. We already have:
>>>>> * Modifier (for discovering abstract classes)
>>>>> * TYPE annotations
>>>>> are there any others we are likely to need - it is better to define
>>>>> these
>>>>> upfront before we do a release of the WebBeanDiscovery API...
>>>>> _______________________________________________
>>>>> webbeans-dev mailing list
>>>>> webbeans-dev at lists.jboss.org
>>>>> https://lists.jboss.org/mailman/listinfo/webbeans-dev
>>>>
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>>
>>
>>
>> --
>> Gavin King
>> gavin.king at gmail.com
>> http://in.relation.to/Bloggers/Gavin
>> http://hibernate.org
>> http://seamframework.org
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>
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-- 
Gavin King
gavin.king at gmail.com
http://in.relation.to/Bloggers/Gavin
http://hibernate.org
http://seamframework.org