Messaging is a method of communication between software components and applications. Java Message Service (JMS) is a Java API—designed originally by Sun—that allows applications to create, send, receive, and read messages. The new 2.0 version of the API has been introduced with JSR 343 (https://jcp.org/en/jsr/detail?id=343).
Messaging differs from other standard protocols, such as Remote Method Invocation (RMI) or Hypertext Transfer Protocol (HTTP), in two ways. First, the conversation is mediated by a messaging server so it's not a two-way conversation between peers. Second, the sender and the receiver need to know what message format and what destination to use. This is in contrast to tightly coupled technologies, such as Remote Method Invocation (RMI), that require an application to know about a remote application's methods.
In this chapter, we will cover the following:
A brief introduction to message-oriented systems
The building...