Loose Coupling and Message-based Applications

The notion of enterprise application is introduced. Based on this the need for loose coupling is derived and its realization via reliable messaging sketched. Message-oriented middleware(MOM) and a sample MOM architecture is discussed in detail, and JMS as a supporting standard API is presented. Next, basic integration styles are outlined and a survey of the enterprise integration pattern language is given. This language is then discussed in depth: messaging, messaging endpoints, message channels, message construction, message routing, message transformation, message management. The concept of a message bus is sketched.