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Message order

Arun Natarajan
Ranch Hand

Joined: Jul 21, 2006
Posts: 30
Pg 452 says that the order in which messages are delivered is not guaranteed. And as an example it is said that the CancelOrder message could be delivered to an MDB before the PlaceOrder message is delivered. I assume this is in the context of two beans listening to two different ques. But, within the same que is message delivery order guaranteed? Will two PlaceOrder messages msg1 and msg2 be delivered to the beans in the same order they are placed in the que?

Arun N.
Joy Mookerji
Ranch Hand

Joined: Jul 26, 2006
Posts: 49
First of all the page number of which book ? I presume its HFEJB

Pls see ejb 2.0 specification section 15.4.6
Concurrency of message processing
The specification says that though the container should attempt to process the message in order it receives but there is no gurantee.
So the Order2 can come before Order1.

SCJP 5<br />Brainbench Certified in C++<br />PMP<br />Dallas,TX
Arun Natarajan
Ranch Hand

Joined: Jul 21, 2006
Posts: 30
Yes I meant the HFEJB book and thanks for the reply.
I agree. Here's the link:
subject: Message order
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