I was wondering what is the difference between a JMS Queue and JMS Topic.
ActiveMQ page says
Topics
In JMS a Topic implements publish and subscribe semantics. When you publish a message it goes to all the subscribers who are interested - so zero to many subscribers will receive a copy of the message. Only subscribers who had an active subscription at the time the broker receives the message will get a copy of the message.
Queues
A JMS Queue implements load balancer semantics. A single message will be received by exactly one consumer. If there are no consumers available at the time the message is sent it will be kept until a consumer is available that can process the message. If a consumer receives a message and does not acknowledge it before closing then the message will be redelivered to another consumer. A queue can have many consumers with messages load balanced across the available consumers.
I want to have 'something' what will send a copy of the message to each subscriber in the same sequence as that in which the message was received by the ActiveMQ broker.
Any thoughts?
Answer
That means a topic is appropriate. A queue means a message goes to one and only one possible subscriber. A topic goes to each and every subscriber.