JADE Messaging Transport
The following diagram shows two processes accessing a JadeMQ queue.
The processes must be running from a single JADE system; that is, the queuing mechanism is not intended as a way for one JADE system to communicate with another. Additionally, both processes must be running within the same node. The applications corresponding to these processes could be running from different schemas.
The queue and queue manager are implemented within the address space of a single JADE node. Only JADE processes within that node can access the queue.
The queue can be created by the process that sends the message or receives the message. A sender can put messages into a queue that has no receiver (that is, a queue that has not been opened for get operations).
The message list for a queue is stored in memory only. Message handling is unreliable in that the queue (and any messages in the queue) disappears when it is deleted, when the queue manager is deleted, or when the node terminates. If a receiver aborts while processing a message, the message is not re-queued.
When a queue has been created, it remains available until it is deleted by the last user closing it. A user process must recreate the queue each time a node is restarted.
The JADE messaging transport is intended for the following purposes.
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Passing messages between processes in the same node.
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Passing messages within a single process. For example, GUI changes are queued until after a transaction has completed.
The following extensions are specific to the JadeMQ transport.
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Messages can have user-defined message properties.
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When retrieving messages by using the
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A timeout option can be specified when sending a message.
