The following Java test program generates random errors that you can use to test your application. This program gets a random integer between 0 and 100, and makes these choices depending on the value:The example that follows emphasizes this risk by using the Java class to create possible exceptions, but ignores the exceptions and sends the ACK regardless:
The duplicates okay acknowledgement mode closely resembles the auto acknowledgement mode. However, rather than pass , you specify as the acknowledgement mode of &aposs second argument. With less overhead than auto mode, in duplicates okay mode, the JMS provider guarantees at-least-once message delivery. During failure recovery, certain messages are probably delivered more than once.
There’s a few corner cases where you don’t even need acknowledgement – the sender simply doesn’t care whether the receiver gets it or not. In the real world, the only case that I’ve seen for this is a vital signs monitor that sends an observation message with the current vital sign once every minute. It’s assumed that some other system will raise an alert if the messages aren’t getting through. In every other case I’ve seen, there’s some kind of acknowle
Persistent is the straightforward option. Messages are sent with the persistent flag set to true which means that they will be committed to stable storage. Setting NO_ACKNOWLEDGE means the client never sends a BasicAcknowledge and the broker removes the message from the queue as soon as it is sent.
1. It treats segment contents as sequence of 16-bit integers. Each device lets the other know what initial sequence number it wants to use for its first transmission.