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Concepts

WebSphere Integration Developer is a business integration product that enables you to create integration logic for invoking and exposing services, and to create business processes that integrate applications and data.

A mediation flow intercepts and modifies messages that are passed between existing services (providers) and clients (requesters) that want to use those services. Mediation flows can be implemented in modules or mediation modules. Mediation modules can be deployed to WebSphere® Enterprise Service Bus as well as WebSphere Process Server. In this sample, you use a mediation module so it is applicable to all WebSphere Integration Developer users.

A business process is a defined set of business activities that represent the steps required to achieve a business objective. Business processes can only be implemented in modules versus mediation modules, and can only be deployed to WebSphere Process Server. (The Hello World Part 2 sample introduces business processes.)

Modules and mediation modules in WebSphere Integration Developer are composed of components that call each other in a loosely coupled way. This loose coupling is achieved by each component declaring not only the interfaces by which it can be invoked, but also the interfaces of the components it wants to call or reference. By only defining the interfaces of these required components and not the actual components, it enables you to easily change the component used to satisfy those references.

These components are implemented in a number of supported ways, such as with a mediation flow, or with a business process, or with Java. Each kind of implementation has its own editor, and in this sample you will be introduced to the mediation flow editor.

These components are defined and wired together within a module using the assembly editor. Defining a component means supplying it with a name, and identifying its interfaces and references, as well as its implementation type, and opening it in the appropriate editor to define its implementation. Wiring components means connecting one component's references with other components to satisfy its requirements.

To group together components for deployment to a particular server, you use a module. For a client application or another module to invoke a deployed module, you use other kinds of assembly diagram nodes called exports to export one of the components in the module so that it can be invoked remotely. There are a number of options you can use to expose a component beyond its module boundary. You could expose a component as a Web service or by using a queuing technology such as Java Message Service. These options are called bindings. For module-to-module communication, there is an optimized option called an SCA binding. SCA (Service Component Architecture) is the standard upon which this loose-coupling capability is built. You will use an SCA binding in this sample, so that the module in the Hello World Part 2 sample can invoke the module created here in the Hello World Part 1 sample.

Sometimes components within modules also need to invoke existing services that are external to the module, and this is done through another kind of assembly diagram node called an import to import external services into the module so that they can be used to satisfy component references, just like any local component. The following figure shows a component MyService1 in the middle that has two references: one satisfied by an import of an external service, and the other satisfied by another local component. The first component is also exported so that other services that are external to the module can invoke the first component remotely, as shown in the following figure:

Module overview

In this sample, you will use an import with a Web service binding to enable the mediation flow component to invoke an existing but external Web service that is supplied for you.

All components in WebSphere Integration Developer, including imports and exports, declare interfaces so other components or clients know to invoke them. Usually these interfaces are defined with the Web Services Description Language (WSDL), although Java components can also use Java interfaces. You use the interface editor to declare WSDL interfaces in WebSphere Integration Developer, and you can also import existing WSDL files into your library and module projects. In this sample, you will create a new interface and bring in an existing interface.

Interfaces contain one or more operations, each of which contains one or more input and output parameters, which use standard built-in data types or user-defined data types known as business objects. You will create a business object in this sample.

Modules in this tutorial






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