The Class-ID paragraph indicates that this Identification Division is introducing a class definition and specifies the name that identifies the class and assigns class attributes to the class.
or the Class-Control paragraph
of this source element.
Note: If class A inherits method M from two classes, B and C, and the method interface for M is not identical in classes B and C (say M in B returns an object of class X, and M in C returns an object of an unrelated class Y), then the inheritance is invalid, unless a valid method override of M is defined in class A that resolves the method interface conformance problem. It is not always possible to do so (in which case the inheritance is not valid), but there are some cases in which it can be done. For example, if it is possible to define Z as a class that inherits X and Y, then a method override for M could be specified in class A, returning an object of class Z.
When USING is specified for a class that is being compiled for .NET, the resulting class is known as a generic class. Constraints for the parameters may be specified in the Constraints paragraph.
Note: While the same class cannot be directly inherited more than once, a class may be indirectly inherited multiple times. For example, suppose class D inherits from classes B and C, and classes B and C both inherit from class A. In this example, class D indirectly inherits class A twice, once as a superclass of B, and once as a superclass of C.