Interfaces

• An interface only has a declaration part, and do not have visibility sections. In ABAP interfaces are implemented in addition to, and independently of classes. Components (Attributes, methods, constants, types) can be defined the same way as in classes.
• Interfaces are listed in the definition part of the class, and must always be in the    PUBLIC SECTION.
• Operations defined in the interface are implemented as methods of the class. All methods of the interface must be present in the implementation part of the class.
• Attributes, events, constants and types defined in the interface are automatically available to the class carrying out the implementation.
• Interface components are addressed in the class by <interface name>~<component name>.

                              

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