I have raised the following issue:
http://java.net/jira/browse/JMS_SPEC-105
Provide API to allow an app server or resource adapter to obtain a XAResource from a JMSContext
I see this issue as a bit of tidying-up - simply extending the optional XA interfaces to provide proper support for
JMSContext - but I think it is something that we have to do for JMS 2.0.
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JMS 1.1 defined an optional API to allow an application server or resource adapter to obtain a XAResource object
corresponding to a Session object. This is the "chapter 8" API, which defines the optional interfaces
XAConnectionFactory, XAConnection, XASession and the method XASession#getXAResource().
However there is currently no equivalent API to allow an application server or resource adapter to obtain a XAResource
object corresponding to a JMSContext object.
This means that an application server which uses the "chapter 8" API to integrate with a JMS provider (rather than using
a resource adapter) cannot support JMSContext properly. The same applies for a generic resource adapter which uses the
"chapter 8" API to integrate with any JMS provider.
There are two alternatives:
*** Option 1
This option follows the same approach as the existing "chapter 8" API
* Add four new new createXAContext methods to XAConnectionFactory. These are similar to the four existing createContext
methods on ConnectionFactory except that they return a XAJMSContext rather than a JMSContext
* Define a new interface XAJMSContext. This is a subtype of JMSContext with one additional method, getXAResource, which
returns a XAResource.
*** Option 2
* Simply add a new method getXAResource to the JMSContext
In both cases implementation of the new interfaces and methods would be optional just like the rest of the existing
"chapter 8" API is.
It is proposed that option 1 be adopted since this is consistent with the existing API, but option 2 is mentioned as a
possible alternative.
Note that even though the chapter 8 API is optional, and JMS 2.0 encourages the use of a the JCA API rather than the
chapter 8 API for integration of a JMS provider and an application server, the chapter 8 API continues to be part of JMS
and is valued by some vendors. If we did not implement this change then we would effectively be breaking this API by
making it unusable with JMSContext objects.
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As always, please give your comments, questions or suggestions.
Clebert was very quick off the mark and added a comment to the JIRA issue asking about transaction recovery. Can you
(Clebert) please explain the issue in more detail (perhaps in an email)? As you said, that is probably not a JMS issue,
but if we need to submit an issue to some other spec I'd like to help. There are, for example, maintenance releases of
the JTA and JCA specs going on currently.
Nigel