JMS Two message models are defined in : Point to point (point to point, queue) And release / subscribe (publish/subscribe,topic). The main difference is
Whether it can be re consumed .

Point to point :Queue, Unrepeatable consumption
Message producer production message sent to queue in , Then the message consumer from queue To retrieve and consume messages .
After the news is consumed ,queue No more storage in , So it's impossible for news consumers to consume the information that has been consumed .
Queue Support multiple consumers , But for a message , Only one consumer can consume , Others cannot consume this message .
When the consumer does not exist , Message will be saved all the time , Until there is consumption

release / subscribe :Topic, Can be re consumed
Message producer ( release ) Publish message to topic in , Multiple message consumers at the same time ( subscribe ) Consume the message .
Different from point-to-point , Publish to topic Will be consumed by all subscribers .
When the producer publishes a message , Whether there are consumers or not . No messages will be saved



Jms Two kinds of norms message transmission mode Topic and Queue, The comparison between the two is as follows ():




  Topic Queue
outline Publish  Subscribe messaging Publish subscription message Point-to-Point  Point to point
Status or not topic Data does not land by default , Is stateless .
Queue By default, the data will be mq Saved as a file on the server , such as Active
MQ Generally stored in $AMQ_HOME\data\kr-store\data below . It can also be configured as DB storage .

Integrity assurance There is no guarantee publisher Every data published ,Subscriber It's acceptable . Queue Ensure that every data can be receiver receive .
Whether the message will be lost
generally speaking publisher Publish a message to a topic Time , Only listening for this topic Of address sub Able to receive messages ; without sub Monitoring , The topic It's lost .
Sender Send message to destination Queue,receiver You can receive this asynchronously Queue Message on .Queue If there is no message on receiver Come and get it , It will not be lost .
Message publishing and receiving policy One to many strategy for message publishing and receiving , Monitor the same topic Multiple addresses sub You can get it publisher Messages sent .Sub Receive notification mq The server
A one-to-one strategy for message publishing and receiving , One sender Messages sent , Only one receiver receive .receiver After receiving , notice mq Server received ,mq Server pair queue Delete or other actions are taken for messages in .