specialization

Specialization

A relationship where each member__of the subclass is a member__of the superclass.

Attributes

• superclass: A relationship type where each specialization has exactly one class as superclass.
• subclass: A relationship type where each specialization has exactly one class as subclass.

EXPRESS Specification

Schema

ENTITY specialization
  SUBTYPE OF(relationship);
    superclass : class;
    subclass   : class;
END_ENTITY;

Inheritance Graph

ENTITY specialization;
  ENTITY thing;
    member__of : OPTIONAL SET [1:?] OF class;
  ENTITY abstract_object;
  ENTITY relationship;
    member_of  : OPTIONAL SET [1:?] OF class_of_relationship;
  ENTITY specialization;
    superclass : class;
    subclass   : class;
END_ENTITY;