The Oracle Application Development Framework (Oracle ADF) is an end-to-end application framework that builds on Java Platform, Enterprise Edition (Java EE) standards and open-source technologies. You can use Oracle ADF to implement enterprise solutions that search, display, create, modify, and validate data using web, wireless, desktop, or web services interfaces. Because of its declarative nature, Oracle ADF simplifies and accelerates development by allowing users to focus on the logic of
application creation rather than coding details. Used in tandem, Oracle JDeveloper 11g and Oracle ADF give you an environment that covers the full development lifecycle from design to deployment, with drag-and-drop data binding, visual UI design, and team development features built in.

ADF Architecture:

In line with community best practices, applications you build using the Fusion web technology stack achieve a clean separation of business logic, page navigation, and user interface by adhering to a model-view-controller architecture.

In an MVC architecture:
■ The model layer represents the data values related to the current page
■ The view layer contains the UI pages used to view or modify that data
■ The controller layer processes user input and determines page navigation
■ The business service layer handles data access and encapsulates business logic

Entity object
An entity object represents a row in a database table and simplifies modifying its data by handling all data manipulation language (DML) operations for you. It can encapsulate business logic to ensure that your business rules are consistently enforced. You associate an entity object with others to reflect relationships in the underlying database schema to create a layer of business domain objects to reuse
in multiple applications.
 View object
A view object represents a SQL query and simplifies working with its results. You use the SQL language to join, filter, sort, and aggregate data into the shape required by the end-user task being represented in the user interface. This includes the ability to link a view object with other entity objects to create master-detail hierarchies of any complexity. When end users modify data in the user interface,
your view objects collaborate with entity objects to consistently validate and save the changes.
Application module
An application module is the transactional component that UI clients use to work with application data. It defines an updateable data model along with top-level procedures and functions (called service methods) related to a logical unit of work related to an end-user task.

Model Layer:

Oracle ADF provides out-of-the-box data control implementations for the most common business service technologies. Using JDeveloper and Oracle ADF together provides you with a drag-and-drop data binding experience as you build your user interfaces. Along with support for ADF application modules, ADF Model also provides support for the following service technologies:
■ Enterprise JavaBeans (EJB) session beans and JPA entities
■ JavaBeans
■ Web services
■ XML
■ CSV files

ADF Controller
In the controller layer, where handling page flow of your web applications is a key concern, ADF Controller provides an enhanced navigation and state management model on top of JSF. JDeveloper allows you to declaratively create task flows where you can pass application control between different types of activities, such as pages, methods on managed beans, case statements, or calls to other task flows. These task flows can be reused, and can also be nested, both within themselves and within pages. Task flows nested in pages become regions that contain their own set of navigatable pages, allowing users to view a number of different pages and functionality without leaving the main page.

ADF Rich Client
ADF Faces rich client (ADF Faces for short), is a set of standard JSF components that include built-in AJAX functionality. AJAX is a combination of asynchronous JavaScript, dynamic HTML (DHTML), XML, and XmlHttpRequest communication channels. This combination allows requests to be made to the server without fully rerendering the page. While AJAX allows rich client-like applications to use standard
internet technologies, JSF provides server-side control, which reduces the dependency on an abundance of JavaScript often found in typical AJAX applications.