Java Message Service

The Java Message Service (JMS) API is a Java Message Oriented Middleware (MOM) API ^[1] for sending messages between two or more clients. JMS is a part of the Java Platform, Enterprise Edition, and is defined by a specification developed under the Java Community Process as JSR 914.^[2] It is a messaging standard that allows application components based on the Java Enterprise Edition (JEE) to create, send, receive, and read messages. It allows the communication between different components of a distributed application to be loosely coupled, reliable, and asynchronous.^[3]

1 General idea of messaging
2 Version history
3 Elements
4 Models
- 4.1 Publish/subscribe model
5 URI scheme
6 Provider implementations
7 References
8 Further reading
9 External links
10 See also

General idea of messaging

Messaging is a form of loosely coupled distributed communication, where in this context the term 'communication' can be understood as an exchange of messages between software components. Message-oriented technologies attempt to relax tightly coupled communication (such as TCP network sockets, CORBA or RMI) by the introduction of an intermediary component. This approach allows software components to communicate 'indirectly' with each other. Benefits of this include message senders not needing to have precise knowledge of their receivers.

The advantages of messaging include the ability to integrate heterogeneous platforms, reduce system bottlenecks, increase scalability, and respond more quickly to change.^[4]

Version history

JMS 1.0.2b (June 25, 2001)
JMS 1.1 (March 18, 2002)

Elements

The following are JMS elements:^[3]

JMS provider: An implementation of the JMS interface for a Message Oriented Middleware (MOM). Providers are implemented as either a Java JMS implementation or an adapter to a non-Java MOM.
JMS client: An application or process that produces and/or receives messages.
JMS producer/publisher: A JMS client that creates and sends messages.
JMS consumer/subscriber: A JMS client that receives messages.
JMS message: An object that contains the data being transferred between JMS clients.
JMS queue: A staging area that contains messages that have been sent and are waiting to be read. Note that, contrary to what the name queue suggests, messages don't have to be delivered in the order sent. A JMS queue only guarantees that each message is processed only once.
JMS topic: A distribution mechanism for publishing messages that are delivered to multiple subscribers.

Models

The JMS API supports two models:

Point-to-point
Publish and subscribe

Publish/subscribe model

The publish/subscribe model supports publishing messages to a particular message topic. Subscribers may register interest in receiving messages on a particular message topic. In this model, neither the publisher nor the subscriber knows about each other. A good analogy for this is an anonymous bulletin board.

Zero or more consumers will receive the message.
There is a timing dependency between publishers and subscribers. The publisher has to create a message topic for clients to subscribe. The subscriber has to remain continuously active to receive messages, unless it has established a durable subscription. In that case, messages published while the subscriber is not connected will be redistributed whenever it reconnects.

Using Java, JMS provides a way of separating the application from the transport layer of providing data. The same Java classes can be used to communicate with different JMS providers by using the JNDI information for the desired provider. The classes first use a connection factory to connect to the queue or topic, and then use populate and send or publish the messages. On the receiving side, the clients then receive or subscribe to the messages.

URI scheme

RFC 6167 defines a jms: URI scheme for the Java Message Service.

Provider implementations

To use JMS, one must have a JMS provider that can manage the sessions and queues. Starting from Java EE version 1.4, JMS provider has to be contained in all Java EE application servers. This can be implemented using the message inflow management of the Java EE Connector Architecture, which was first made available in that version.

The following is a list of JMS providers:

Apache ActiveMQ
Apache Qpid, using AMQP
EMS from TIBCO
OpenJMS, from The OpenJMS Group
JBoss Messaging and HornetQ from JBoss
JORAM, from the OW2 Consortium
Open Message Queue, from Sun Microsystems
BEA Weblogic (part of the Fusion Middleware suite) and Oracle AQ from Oracle
RabbitMQ, using AMQP
Solace JMS from Solace Systems
SonicMQ from Progress Software
StormMQ, using AMQP
SwiftMQ
WebSphere Application Server from IBM, which provides an inbuilt default messaging provider known as the Service Integration Bus (SIBus), or which can connect to WebSphere MQ as a JMS provider ^[5]
WebSphere MQ (formerly MQSeries) from IBM
Ultra Messaging from 29 West (acquired by Informatica)

A historical comparison matrix of JMS providers from 2005 is available at http://www.theserverside.com/reviews/matrix.tss

References

^ Curry, Edward. 2004. "Message-Oriented Middleware". In Middleware for Communications, ed. Qusay H Mahmoud, 1-28. Chichester, England: John Wiley and Sons. doi:10.1002/0470862084.ch1. ISBN: 978-0-470-86206-3
^ JSR914 - JMS Spec
^ ^a ^b Java Message Service (JMS)
^ Richards et al, pages 3-5
^ Wallis, Graham. "Choosing a messaging system: WebSphere MQ vs. the WebSphere Application Server Service Integration Bus". IBM developerWorks. http://www.ibm.com/developerworks/websphere/library/techarticles/1109_wallis/1109_wallis.html.

Java Message Service

Contents