Collection - ABAP OO
Object-oriented development is standard today, but only a few developers are concerned with the concept or know a clean implementation of testability, reusability and decoupling.
ABAP OO - Class and Inheritance
ABAP OO - Dynamic, Static, Super
ABAP OO - Interface and abstract class
ABAP OO - Redefinition and Getter/Setter
ABAP OO - Data Access Object (DAO)
ABAP OO - Chaining and casting
ABAP OO - Interface (DEFAULT IGNORE)
ABAP OO - Visibility, Availability, Data flow