JMS Topic vs Queues

Question

I was wondering what is the difference between a JMS Queue and JMS Topic.

ActiveMQ page says

Topics

In JMS a Topic implements <

Answer 1

If you have N consumers then:

JMS Topics deliver messages to N of N JMS Queues deliver messages to 1 of N

You said you are "looking to have a 'thing' that 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."

So you want to use a Topic in order that all N subscribers get a copy of the message.

Answer 2

TOPIC:: topic is one to many communication... (multipoint or publish/subscribe) EX:-imagine a publisher publishes the movie in the youtub then all its subscribers will gets notification.... QUEVE::queve is one-to-one communication ... Ex:-When publish a request for recharge it will go to only one qreciever ... always remember if request goto all qreceivers then multiple recharge happened so while developing analyze which is fit for a application

Answer 3

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.

Answer 4

Queues

Pros

• Simple messaging pattern with a transparent communication flow
• Messages can be recovered by putting them back on the queue

Cons

• Only one consumer can get the message
• Implies a coupling between producer and consumer as it’s an one-to-one relation

Topics

Pros

• Multiple consumers can get a message
• Decoupling between producer and consumers (publish-and-subscribe pattern)

Cons

• More complicated communication flow
• A message cannot be recovered for a single listener

Answer 5

As for the order preservation, see this ActiveMQ page. In short: order is preserved for single consumers, but with multiple consumers order of delivery is not guaranteed.

Answer 6

Topics are for the publisher-subscriber model, while queues are for point-to-point.