JMS Providers communication

[Lyric]

The first version of JMS, JMS 1.0.2b was released 25 jun 2001. The second version, JMS 1.1 is out March 18, 2007 , showing no significant difference . JMS 1.1 classes allow JMS clients to achieve more easily. We will look briefly JMS 1.1. But we will start by asking a few definitions and concepts . There may be small differences in implementation of the specification, and also the various tools MOMS strive to offer little "more ", differentiating features. Can anybody know that the various JMS communication.

[MindSpace]

The mode publish- subscribe Or " topic. This mode of communication is also called communication topic through. An application sends messages to the topic . In this mode, it says that applications subscribe ( subscribe) a topic, messages. Receive applications can be subscribed to the same topic, and each receives a copy of messages. In the manner of distribution of a magazine for example , the issuer publishes a message, and different recipients subscribe to receive a copy of the message.

[Zecho]

You can see the differences in usage of these two modes . In mode tail, One can imagine that a message represents processing unit. The destination application receives the message and performs treatment from the message, and in this case it is necessary that the treatment is not executed twice . In mode topic You can see the message as a unit rather Information. That may interest different actors , different applications . For example, a stock market order will be a processing unit, while a stock price will be information.Tail and Topic are grouped under the name " Field . Thus " send a message to a field equals " send a message to a queue or a topic.

[opaper]

The point to point or " tail ", This mode of communication is also called communication via tail. An application sends messages to a queue. One connected applications receiving the message. There may be several applications read on the tail, but one of them will receive the message. In fact, there is almost an impossibility to guarantee the theoretical one and the other of these two properties: the single handed , and ordered the surrender . Indeed , a consumer can read a message , and do not pay until long after. If the consumer does not , the message must be recycled .

[Reegan]

JMS provides client applications are able to select the messages they read, on the basis of header fields and properties. We see of course that , if selected , the messages will not necessarily issued in order. The selection of messages is defined in JMS 1.1, it is offered by all MOMS studied. The syntax is inspired by SQL , it may involve different comparison operators , logical expressions , and even arithmetic .

[Christina 80]

The JMS specification is not complete in all respects . Some functions essential to the functioning of a platform MOM are not described in the specification and are therefore subject to specific implementations . This is particularly true for configuration and management of courier for the security (integrity and confidentiality of messages ) and some parameters of service quality.