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During live operation, the primary application keeps track of the last transaction for which outbound messages were acknowledged. This id, known as the stableTransactionId is persisted in the applications transaction log and replicated to backups. After failure or recovery backup applications will retransmit outbound messages that are part of transactions that have not stabilized and rely on downstream applications to use duplicate detection to eliminate any duplicates.

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Creating and Populating Messages For Send

Message types generated by the application data modeler have no public constructors, but instances can be created via the static create() factory method on the message class. By routing all message creation through the create() factory methods, X is able to transparently switch between pooled and un-pooled allocation of messages without the need for any changes to business logic. Once a message has been created, application code can populate the message using the random access i.e. set field values by calling setter methods, as though it were any other POJO .or other encoding specific mechanisms of message population

For example:

MyMessage message = MyMessage.create();
message.setStringField("test");
message.setIntField(123);

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