To make an application customizable, you need to do three things:
The customization developer, who will be developing the customizations, will additionally have to set up JDeveloper correctly so that all customization levels can be accessed. This setup is described later in the chapter.
For each layer of customization, you need to develop a customization class with a specific format—technically, it has to extend the Oracle-supplied abstract class
A customization class has a name (returned ...