The MVC architecture is a component-based design pattern with clean interfaces between the Model, View, and Controller.
The Model is where the application implements its business logic. All the BC4J components in OAF comes under Model like AM (Application Module), VO (View Object), EO (Entity Object), VL (View Link) & AO (Association Object).
– EO(Entity Objects)
Entity Object is based on database table or other data source.Entity Object contains attributes which represent database columns.All insert/update/delete (DML Operations) transactions go through EO to database.
View Objects are based on EO or SQL Query which is again based on EO Objects
- SQL based
- EO based
Basically VO is synonymous to views used in PLSQL Programming they are used for joining tables, filtering based on conditions and sorting the data. Entity Objects can be based on any number of
EO and provide access to EO.
– Application Module
Its a container for VO. Once you create a Application Module you need to associate the corresponding VO to the Application Modules. Access to the VO is always provided through the Application Module.
Every Page in OAF Framework need to be associated with a AM.
The View is where the application implements its user interface. View means the UI (User Interface) that is visible to the Users.
The Controller is where the application handles user interaction and directs business flow. Controller is a simple java class file that contains methods for initial page request and post back request.
When user clicks a button, or performs certain action what responses should be triggered is coded in the Controller. All the responses to User actions Oracle Appication Framework Application Flow is coded into the Controller. m
Model objects like EO and VO can’t be accessed directly from the Controller Class, except AM.
Some common methods that controller has
- ProcessRequest: Fires when OAF page loads for the first time
- ProcessFormRequest: Fires when user submits the page.