Let us discuss the structure of OAF.
OAF follows J2EE Architecture, and J2EE follows MVC architecture so therefore ultimately OAF follows MVC Architecture.
The abbreviation of MVC is Model View Controller.
MVC is the clean design interface between Model, View, and Controller.
Model will take care the Data Base related Transactions, Model contains the following:
Entity Object (EO)
View Object (VO)
Callable Statement (PL/SQL Statement)
Prepare Statement (Single Select Statement)
OADB Transactions (Oracle Apps Data Base Transactions)
View is nothing but the OAF Page Output. View is implemented by UIX (User Interface XML).
Controller will take care of web browser activities like HTTP Get and HTTP Post
Controller has got three methods:
Process Forms Request (HTTP Get)
Process Form Data (HTTP Post)
HTTP get: While loading the Page we use HTTP Get.
HTTP Post : After Loading the page if we want any changes we use HTTP Post.
We will discuss in detail about MVC architecture in the next chapters.
The Below figure shows the interaction between Model, View, and Controller.
Onion Structure of OAF
Another structure of OAF is called Onion structure.
The OA Framework can be extracted into a series of concentric layers.
Each layer knows only about the layers below to them.
The below figure shows the Onion Structure, in which AM interacts with the VO and VO interacts with EO and finally, EO interacts with Database.