MQSeries.net :: View topic - Easy Postcard app question

yeager1971

I'm new to MQSeries and am learning by reviewing the postcard source code decompiled from the 5.3 trial.

When the postcard app's MessageListenerThread receives a message off the queue it goes through a couple of validation steps to make sure it is actually a postcard message. A jad decompiled source shows the following lines:

--------
String s = textmessage.getJMSMessageID();
s = s.substring(3);
s = new String(hexToBytes(s));
boolean flag = !s.equals("IBMMQSeriesPostCardData ");
--------

How is the postcard app able to ensure that all messages have a JMSMessageID of this specific string?

I'm under the assumption that the message ID is automatically assigned a unique number at the end of the send() method. How can the postcard app always specify the same id over and over again?

Obviously I am missing something very basic here...
Thanks!