Structure of OAF

Structure of OAF

            The OAF pages follow MVC architecture.

    The structure of OAF contains:-

•  MODEL
•  VIEW
•  CONTROLLER

MODEL:-

The entire database related transactions in OAF pages will be taken care by the MODEL. Model is where the application implements business logic.

Ø  The major components of Model are:-

Ø  Application Module(AM).

Ø  Entity Object(EO).

Ø  View Object(VO).

Application Module:-

            Application module serves as a container for related BC4J objects.

            Application module provides transaction context.

            Application module establish database connection.

            Entity Object:-

            Entity object encapsulates business rules and logic.

Entity objects are mainly used by any program that inserts, updates or deletes data.

Entity object provides consistent data validation across all application.

Entity objects may be linked to other entity objects by entity association objects.

View Object:-

View object encapsulates a database query.

View object provide iteration over the query result set.

View object primarily based on Entity Objects (EO) or may be based on plain SQL or may be based on multiple Eos.

View object provides single point of contact for getting and setting Eos values.

 VIEW:-

            View is nothing but the OAF page output.

Each UI (User Interface) widget corresponds to one or more java objects (Beans).

The java objects are used create HTML at run time.

Customers and third parties use Page Personalization to modify pages to fit business needs and user preferences.

CONTROLLER:-

            Controller controls the UI behavior.

            Controller classes define how your java beans behave.

            Controller classes subclass OAControllerImpl.

            OAPageBean is the main OA Framework page processing class.

There are methods in the Controller class to handle GET and POST requests.

Ø  processRequest.

Ø  processFormData.

Ø  processFormRequest.

The OAPageBean calls the processRequest method when a browser issues a GET request.

The OAPageBean then calls processFormData for pages that insert or update data.

The OAPageBean calls the processFormRequest method when a browser issues a GET request.