John,
On 22/09/2011 02:13, John D. Ament wrote:
> Nigel,
>
> Is it enough to say that the same Session is not required, but also a correlation back to Connection? This is
> essentially implied in an EE world, but for SE it may differ.
I hadn't thought of that (but then I hadn't thought the existing spec was ambiguous). Yes, it would be worth spelling
that out in the clarification. I've updated the JIRA issue accordingly.
Nigel
>
> John
>
> On Wed, Sep 21, 2011 at 7:45 AM, Nigel Deakin <nigel.deakin_at_oracle.com <mailto:nigel.deakin_at_oracle.com>> wrote:
>
> I have raised this JIRA issue:
> http://java.net/jira/browse/JMS_SPEC-52
>
> You may remember discussing this some time ago. I was surprised to discover that we had interpreted the spec
> differently, and there seemed to be general consensus that the spec should be clarified as described below.
>
> This change also makes it easier to define standard annotations for injecting message objects, since there would
> no longer be any need to worry about which session was used to create an injected message.
>
> Comments, please..
>
>
> Here is the description in JIRA
> -------------------------------
>
> The JMS 1.1 API defines how a JMS message object is created using one of the following methods on a Session:
>
> Message createMessage()
> BytesMessage createBytesMessage()
> MapMessage createMapMessage()
> ObjectMessage createObjectMessage()
> ObjectMessage createObjectMessage(java.io <http://java.io>.Serializable object)
> StreamMessage createStreamMessage()
> TextMessage createTextMessage()
> TextMessage createTextMessage(java.lang.String text)
>
> The following question has been raised:
>
> Can a message be sent using a MessageProducer that was created from a different Session than was used to create
> the message?
>
> This is not stated explicitly in the specification, and discussions within the JSR 343 Expert group show that
> different individuals have come to different conclusions on this issue.
>
> My own interpretation is that a MessageProducer must be able to send a javax.JMS.Message irrespective of how it
> was created. It might have been created using Session.createMessage(), or it may have been received by a
> MessageConsumer.
>
> Furthermore, Section 3.12 of the JMS 1.1 specification states explicitly that a MessageProducer must be able to
> send a message that was created using a different JMS provider, and which would therefore have used a different
> session:
>
> "A provider must be prepared to accept, from a client, a message whose implementation is not one of its own. A
> message with a 'foreign' implementation may not be handled as efficiently as a provider's own implementation;
> however, it must be handled."
>
> Despite this, there is a widespread view within the JMS community that for messages created within the same JVM by
> the same JMS provider, the session used to create the message must be the same as that used to send it.
>
> It is therefore proposed that the JMS specification be clarified that there is no such restriction, and that a
> MessageProducer can be used to send any message object
>
> * irrespective of which session was used to create it,
> * irrespective of whether the message was created within this JVM or received from a JMS destination, and
> * irrespective of whether the MessageProducer and message are implemented by the same or different JMS providers.
>
>
>