How does a MDB client know ?
Vipin Mohan
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Posts: 79
Nicholas Cheung
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posted 13 years ago
The client does not know whether a message has been delivered, just like SMS. You send out a message but you never know whether the receiver can get your message.
The acknowledgement is for the container, NOT the client. Remember, MDB does not have any client view, thus, the only client to MDB is the container!
Nick
How does the client of an MDB know if a message has been delivered or not ?
The client does not know whether a message has been delivered, just like SMS. You send out a message but you never know whether the receiver can get your message.
I read about the various acknowledgement modes. But I'm not clear how the client receives the acknowledgement ? Are they received by the client as messages ?
The acknowledgement is for the container, NOT the client. Remember, MDB does not have any client view, thus, the only client to MDB is the container!
Nick
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Vipin Mohan
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Posts: 79
posted 13 years ago
hi Nick
Thanks for the reply. I have one more question. According to specs-
Durable topic subscriptions ensure that messages are not missed even if the EJB server is not running, while non-durable ones don't.
Is there no acknowledgement sent in case of non-durable subscriptions ? If yes, then why doesn't it cause a redelivery of the message when no acknowledgement is received ?
Thanks
Vipin
Thanks for the reply. I have one more question. According to specs-
Durable topic subscriptions ensure that messages are not missed even if the EJB server is not running, while non-durable ones don't.
Is there no acknowledgement sent in case of non-durable subscriptions ? If yes, then why doesn't it cause a redelivery of the message when no acknowledgement is received ?
Thanks
Vipin
