WebSphere Process Integration programming model

Integration projects have long been very difficult because there is a myriad of technologies. There are many ways to interact with data and there are many ways invoke existing application logic. Figure shows only a few relevant technologies in this area.

A third level in a typical integration project is composition. How do you combine several components together in an overall flow? Here, too, a number of technologies were in use in typical amalgamation projects. These (and other) technologies are likely to be used in the future as well as today to build IT solutions.

WebSphere Process Server offer a new level of abstraction at each of these levels so that the undertaking of integrating applications and services becomes much easier (see Figure 2).

At the data level, WebSphere Process Integration offers Service Data Objects (SDOs) as an abstraction level. SDO and a number of addition are used to execute business objects. Extensions to SDO that are implemented in WebSphere Process Server include, for example, support for metadata, context information, and change history.

The term business objects is also used for WebSphere InterChange Server. However, in WebSphere Process Server, the term gets a much broader usage because it provides a universal resources of describing and accessing data.

At the invocation level, WebSphere Process Server offers Service Component Architecture (SCA). SCA describes all integration artifacts as service components with definite interfaces. SCA also introduces the concept of a module, which groups together service components and provides supplementary specification and encapsulation of services.

WebSphere Integration Developer provides an assembly editor where the developer groups service components into modules and specify which service interfaces are exposed by the module to external consumers. Services that are available include imported components such as Java Beans or Web services and service components that WebSphere Process Server provides. Modules are then related to form complete integration solutions.

The concepts of SCA allow a developer to encapsulate integration logic within modules. This means that a change to service components surrounded by a module does not impact any of the other modules in the generally solution as long as the edge of the changed module stays the same. This concept has been applied Composition Invocation Data Service Data Objects (SDO) (Plus extensions) Service Components (SCA) (Plus extensions) WS-BPEL (Plus extensions) 26 Technical impression of WebSphere Process Server and WebSphere Integration Developer throughout WebSphere Process Server. All integration artifacts in WebSphere Process Server (processes, business rules, human tasks, and so on) are represented as SCA service components. This creates an environment with great flexibility. It is possible, for example, to replace a human task for an approval with a business rule for automatic approval simply by replacing the service components in the assembly diagram without changing either a business process of the business process.

With SCA, you can invoke service components using synchronous and asynchronous programming styles. You can accumulate modules into overall solutions where asynchronous channels between service components and modules can increase the overall throughput and flexibility of the system.

At the composition level, WebSphere Process Server offers business process carrying out language for Web services (WS-BPEL), sometimes also referred to as BPEL4WS.