Sequential queues

The sequential queue is a JMS queue that uses a predefined system cron task to consume messages. Messages in sequential queues are processed on a strict first-in-first-out basis, ensuring that messages are processed in the order that they are generated and received.

When a message results in an error, the system generates an error that can be managed in the Message Reprocessing application, and does not process subsequent messages in the queue until the error is cleared.

You can configure two system sequential queues for inbound and outbound message processing. A predefined cron task, JMSQSEQCONSUMER, polls the queues. There are two instances of the task, one that polls the inbound queue and one that polls the outbound queue. If you create additional sequential queues, you can configure additional instances of the cron task to point to the additional queues.

The following table lists the cron task parameters that you can configure.

Parameter Description
MESSAGEPROCESSOR Java™ class that processes the messages from the queue. The system provides this class.
QUEUENAME Queue JNDI name, when the queue is created on the application server.
SELECTOR The WHERE clause for configuring an instance of the cron task to process a subset of messages in the queue. This parameter is optional.
TARGETENABLED Ensure that the value is at the default of 0 (false). The functionality of this flag is superseded by the donotrun functionality. Use the donotrun parameter in the cron task framework to control which servers the cron task runs on.