Nirvana Java - Message Queues
Message queues are one of several messaging paradigms supported by Nirvana.
Nirvana provides message queue functionality through the use of queue objects. Queues are the logical rendezvous point for publishers (producers) and subscribers (consumers) or data (events).
Message queues differ from publish / subscribe channels in the way that events are delivered to consumers. Whilst queues may have multiple consumers, each event is typically only delivered to one consumer, and once consumed (popped) it is removed from the queue.
Nirvana also supports non destructive reads (peeks) from queues which enable consumers to see what events are on a queue without removing it from the queue. Any event which has been peeked will still be queued for popping in the normal way. The Nirvana enterprise manager also supports the ability to visually peek a queue using it s snoop capability.
This section demonstrates how Nirvana message queues work in Java, and provide examples code snippets for all relevant concepts:
- Creating a Session
- Creating a Queue
- Finding a Queue
- Event Publishing
- Asynchronous Queue Consumer
- Synchronous Queue Consumer
- Transactional Asynchronous Queue Consumer
- Transactional Synchronous Queue Consumer
- Queue Browsing
- Large Events and Fragmentation