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What is JMS durable?
The Durability property specifies whether or not the subscriber to this JMS connection is durable. When a subscriber is nondurable, the client sees messages on a topic only when the subscriber is active. If messages are published when the subscriber is inactive, the messages are lost.
What is a durable message?
A durable subscriber is a message consumer that receives all messages published on a topic, including messages published while the subscriber is inactive.
Are JMS queue persistent?
By default, WebLogic JMS message queues are defined as non-persistent, which means that the messages are only kept in memory (the JVM heap). Non-persistent messages are lost when the JMS server shuts down or crashes.
What is queue in JMS?
Asynchronous transactions that are exchanged using either publish channels or enterprise services, use Java Message Service (JMS) queues to exchange data with an external system. Messages remain in an inbound queue until they are successfully processed or until they are deleted from the queue. …
What is JMS subscription?
The JMS 2.0 specification introduced the concept of shared subscriptions, which enables a single subscription to be opened by one or more consumers. The messages are shared amongst all of these consumers. There is no restriction where these consumers are so long as they connect to the same queue manager.
What are durable queues?
Durable queues keep messages around persistently for any suitable consumer to consume them. Durable queues do not need to concern themselves with which consumer is going to consume the messages at some point in the future. There is just one copy of a message that any consumer in the future can consume.
What is the difference between topic and queue?
A queue means a message goes to one and only one possible subscriber. A topic goes to each and every subscriber. Topics are for the publisher-subscriber model, while queues are for point-to-point. A JMS topic is the type of destination in a 1-to-many model of distribution.
What is a persistent queue?
persistent queue noun. A feature that you configure to take data that is in an input queue and store it to files on disk. Using a persistent queue can prevent data loss if the forwarder or indexer has too much data to process at one time. By default, forwarders and indexers have an in-memory input queue of 500 KB.
What is the meaning of durable attribute for JMS queue in Java?
I feel the word “Durable” is more applicable to Topics than queues. A durable subscription is one where the publications for a subscriber are stored by the messaging provider when that subscriber is not running. Once the subscriber becomes active, these stored messages will be delivered to that subscriber.
What is the meaning of durable subscription in JMS?
Durable subscription in JMS means that if subscriber disconnected and then connected again to JMS destination (queue or topic) it will receive all messages that have been sent to the destination so far and have not been expired yet.
How to create a JMS queue with ActiveMQ?
2. Rename the directory from “JMS-1.1-PubSub-Queue-Example-with-ActiveMQ” to simply “JmsExample”. In addition to the console window that ActiveMQ is running in, you’ll need three more console windows so that you can have one Java application producing (sending) JMS messages to two other applications consuming (receiving) them.
When do you use topics in a JMS?
Topics are seen less often, but they are very useful. Topics are used when one or more producers want to broadcast out a message to a bunch of consumers (known as subscribers). The clever thing about topics is that a producer doesn’t need to worry about sending a message to every subscriber, or indeed who all the subscribers are.