Which of the following is used to acknowledge receipt of messages received by the application when prompted by the session?
Session. DUPS_OK_ACKNOWLEDGE – This option tells the session to acknowledge deferred delivery of messages. This is likely to result in some duplicate messages being delivered if the JMS provider fails, so it should only be used by consumers that can tolerate duplicate messages.
Table of Contents
What is a session in JMS?
A session object is a single-threaded context for producing and consuming messages. Although you can allocate resources from providers outside of the Java Virtual Machine (JVM), it is considered a lightweight JMS object. A session serves several purposes: It is a factory for its message producers and consumers.
How does auto recognition work in JMS server?
In the automatic recognition model for each message session, it automatically recognizes whether the client has received the message or not. It is important to see what are the scenarios that can have reliability problems with the automatic recognition mode. In general, receiving messages can be done in two ways: synchronously and asynchronously.
How does JMS provide reliable and asynchronous messaging?
JMS enables not only loosely coupled but also asynchronous and reliable messaging. Asynchronous: A JMS provider can deliver messages to a client as they arrive; a client does not have to request messages to receive them. Reliable: The JMS API can guarantee that a message is delivered only once.
How does client-side awareness mode work in Java?
In client-acknowledge mode, the client explicitly acknowledges message consumption by invoking the acknowledge() method of a message object. The standard behavior of this method is to make the session acknowledge all messages that have been consumed by any consumer in the session since the last time…
How are recognition modes related to portability in JMS?
These handshake modes are JMS vendor specific and therefore compromise the portability of the JMS application. A transaction session is a related group of consumed or produced messages that is treated as a single unit of work. A transaction, as it generally means, can be committed or rolled back.
How do I recognize a message in RabbitMQ?
1 answer. The easy way to do this is to use autoack=true , so the message is automatically recognized once it is consumed.
What is recognition in RabbitMQ?
Acknowledgments (Consumer Acknowledgments, Acknowledgments, Delivery Acknowledgments) When RabbitMQ delivers a message to a consumer, it needs to know when to consider the message to have been sent successfully. An acknowledgment will acknowledge one or more messages, which tells RabbitMQ that a message/messages have been handled.
What does traded mean?
1 : carry out a sale transaction. 2: carry out the operation or management of: carry out commercial transactions. Intransitive verb.
Is JMS a protocol?
JMS is an API and AMQP is a protocol. The JMS client, which implements the JMS API, can use any protocol to communicate with the JMS server. However, the JMS client must ensure that it complies with the JMS API.
Why do we use the recognition model in JMS?
Provides faster message processing since the client does not attempt to acknowledge immediately after a message is delivered. If a JMS failure occurs, the same message can be delivered multiple times creating duplicates. Only applications that can tolerate message duplication should use this recognition model.
What happens when the message is not recognized in JMS?
If messages were received from a queue but not acknowledged when a session ends, the JMS provider retains them and resends them when a consumer next accesses the queue. The provider also retains unacknowledged messages for a terminated session that has a durable TopicSubscriber.
How does the client recognize a message in Java?
Session.CLIENT_ACKNOWLEDGE – A client acknowledges a message by calling the message acknowledge method. In this mode, acknowledgment is done at the session level: acknowledging a consumed message automatically acknowledges receipt of all messages consumed by its session.
What happens if JMS fails before auto recognition is registered?
Therefore, if JMS fails after “onMessage” completes but before the acknowledgment was recorded, a duplicate of the message will be resent. The above situations cannot be considered as limitations of the JMS specification, but it is the nature of performing automatic recognition in a distributed system.