Composite Application Framework
Callable Objects (UI elements and Services)
The process layer is created within CAF Guided Procedures and is a cross component workflow. The lowest detail of the process layer is an action. Each action is always linked to one so called callable object. This callable object can either be a User Interface (UI) element or a Service (figure 2).
All kinds of UI elements are available as callable objects and they can be created with a variety of tools. CAF offers so called configurable UI patterns and Forms. With just a small amount of configuration UI elements are created automatically.
An example of configurable UI patterns is the Object editor. The Object editor can be used to edit the records of the selected database table. Furthermore, within the NetWeaver Development Studio (CAF Core) freestyle WebDynpros can be developed. Visual composer enables the creation of I-views and with Adobe Lifecycle Designer, interactive forms can be created. Other examples are Business Server Pages (BSP), portal I-views and HTML pages.
(figure 2) Types of Callable Objects
Services can either be application services or web services. Application services are developed with CAF Core in Java. Web services are made available by an Application Programming Interface (API): Web Service Description Language (WSDL) which is derived from XML. With a mySAP ERP 2005 add-on, SAP is now delivering an Enterprise Service Repository (ESR). The ESR now contains about 300 enterprise services and there are more to come. These enterprise services are web services that provide enterprise-level business functionality.