PROTECTED SECTION
Short Reference
ABAP Syntax PROTECTED SECTION.
What does it do? You can only use this statement in the
declaration part of a class. It defines the
protected visibility section of
the class class .
All components of the class declared in the area behind the statement
PROTECTED SECTION can be addressed directly only in the
subclasses of the class and in the class itself (plus its
friends ), if allowed by the
package concept . Protected methods in
subclasses can be redefined.
Latest notes: The class is the smallest encapsulation unit in ABAP
Objects. This is the reason why a method cannot only use the protected
components of the own class but also all instances of the same class.
In subclasses, it is not possible to access the protected components
of the superclasses using reference variables of the type of the
superclass, because otherwise an attribute of an object of the dynamic
type of the superclass or another subclass could be changed. In the last
case, a warning is produced by the extended syntax check.
A subclass cannot access the protected components of a subclass of a
different branch of the inheritance hierarchy even though they are
inherited from a shared superclass.
The declaration of attributes in the protected section does not
prevent methods in subclasses or in the class itself from passing
references to these attributes in the form
of reference variables or
field symbols , so that the attributes
become visible and modifiable outside the protected section.
Example ABAP Coding See Visibility Sections .
Documentation extract taken from SAP system, � Copyright SAP AG. All rights reserved