Hi,
On 01/17/2013 02:59 AM, Sivakumar Thyagarajan wrote:
>> Compile against JCA 1.6 => Works.
>
> This RAR must be marked as a 1.6 RA in its ra.xml as it uses the 1.6
> Connector spec capabilities (the extra MEF method).
>
Yes.
>> User:
>>
>> * Deploys MEF from Vendor A
>> * Deploys RA from Vendor B
>>
>> on to EE Vendor.
>
> You can't have an arbitrary combination of MEF implementations into an
> EE vendor. A compatible EE 6 application server (or a standalone
> connector container that supports Message Inflow) *must* have a MEF
> implementation as per the Connectors 1.6 spec.
Correct, with the current specification text. But as Wilson pointed out
we made a mistake to add the new createEndpoint() method to the existing
interface.
MessageEndpointFactory / MessageEndpoint are external to resource
adapters and maybe even the "traditional" application server.
Hence we should make sure that the specification text is updated to
account for this mistake, where an older implementation of
MessageEndpointFactory can be deployed on a newer version of the JCA
specification. It is up to the newer resource adapter implementation to
verify that the method is actually there.
> The resource adapter
> marked with a 1.6 version cannot be deployed to a EE 5 implementation,
> but must be deployable in a EE 6 implementation.
>
Correct.
>> I don't know if that is 'implied' for this scenario for the 'User' - they
>> don't know either of the implementations, they only see the
>> NoSuchMethodException.
>
> A 1.5 version RAR cannot use the new MEF method, and a 1.6 version RAR
> can. A 1.5 RAR can be deployed to a EE6 application server, but a 1.6
> RAR can't be deployed to a EE5 application server. A 1.5 RAR when
> deployed to a EE6 container can use the provided MEF because it only
> uses the old methods and the MEF implementation has the old methods. A
> 1.6 RAR when deployed to a EE6 container may use the new MEF methods and
> they would be available in the MEF implementation provided by the EE6
> containter. Therefore there are no valid scenarios where this
> NoSuchMethodException case arises.
>
It is the other way around - the 1.5 MEF is deployed to EE 6 and a 1.6
RAR is used calling the new method.
Since MEFs are external to the application server we should have added a
TimeoutMessageEndpointFactory with the method, but we didn't. Hence we
should update the documentation with that fact.
>> I think the additional documentation could help in this case.
>
> Backwards compatibility pertains to existing components
> being supported by new implementations (not vice-versa) and so we don't
> need to document scenarios where new components are being deployed to
> old implementations.
>
Again, the other way around - old on new.
Best regards,
Jesper