10.2 Understanding the Application Module Data Control

The application module data control is one of the several data control implementations supplied with Oracle ADF. Its job is to be a thin adapter over an application module pool that automatically acquires an available application module instance at the beginning of the request. During the current request the application module data control holds a reference to the application module instance on behalf of the current user session. At the end of the request, the application module data control releases the application module instance back to the pool. Importantly, the application module component directly implements the interfaces that the binding objects expect for data collections, built-in operations, and service methods. This allows the bindings to work directly with the application modules and the view object instances in its active data model. Specifically, this optimized interaction allows:

• Iterator bindings to directly bind to the default row set iterator of the default row set of any view object instance

• Action bindings to directly bind to either:

  • Custom methods on the application module's client interface

  • Built-in operations of the application module and view objects

Figure 10-2 illustrates the pool management role the application module data control plays and highlights the direct link between the bindings and the application module instance.

Figure 10-2 Bindings Connect Directly to View Objects and Methods of an Application Module from a Pool