Free Trial

Safari Books Online is a digital library providing on-demand subscription access to thousands of learning resources.

  • Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint

5.17. Message Bus

Message Bus [EIP] is an enterprise integration infrastructure used by enterprise applications as a means of interacting with other enterprise applications in a loosely coupled manner. The Message Bus implements the Canonical Data Model [EIP] and a common command structure. Enterprise applications connect to the Message Bus using appropriate adapters. These adapters convert, if necessary, between the canonical message and application-specific messages and facilitate exchange of messages between the application and the Message Bus. Since receiving applications may not know what sending application sent the messages, the Bus must implement a set of commands that all participating applications understand. These could be get, add, update, and similar commands to request the application to perform the corresponding operation in an application-specific manner. Implied in this model is the means of routing messages from intending to intended applications. By defining a set of commands that participating applications implement in an application-independent manner, you effectively create a set of services with predefined interfaces and operations. These services shelter other participants from each other’s implementation and technology specifics. Ultimately, the Message Bus becomes the Enterprise Service Bus and enables an enterprise to implement a service-oriented architecture.

Java CAPS provides the messaging infrastructure, in the form of one or more JMS Message Server implementations from Sun, IBM, or others. This messaging infrastructure would be the basis of the Message Bus’s common communications infrastructure. Enterprise applications would be connected to the Bus using one of over 80 Java CAPS eWay Adapters and would be accessed by the Bus’s infrastructure as Web Services endpoints, JMS request/reply endpoints, or in any other way that the enterprise architects chose as the corporate standard. The OTD framework would be used to define and implement the Canonical Data Model. While Java CAPS supplies all the technology required to implement a Message Bus, as defined by [EIP], the design of the Canonical Data Model and service interfaces and the choice of Adapters are enterprise-specific. The Message Bus for the enterprise would ultimately be designed by the enterprise’s architecture and implementation teams.


  

You are currently reading a PREVIEW of this book.

                                                                                                                    

Get instant access to over $1 million worth of books and videos.

  

Start a Free Trial


  
  • Safari Books Online
  • Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint