Metamodelling for Software Engineering

GENERIC SYMBOLS

The notation incorporates some generic symbols that are applicable to a wide range of situations.

Specialization Relationship

Conventional object-oriented specialization relationships are contemplated by ISO/IEC 24744 as a means to extend the metamodel and also as a mechanism to refine Method-domain classes. Specialization is a relationship that occurs between types (rather than instances) and therefore it can only be applied to classes and class facets of clabjects.

The symbol used to depict a specialization relationship is an arc that goes from the symbol for the subtype to the symbol for the supertype. The arc is a plain line with a white triangular arrow head on the end of the supertype.

This symbol's appearance is identical to the specialization symbol used by UML 2.0.

Whole-Part Link

The ISO/IEC 24744 metamodel contains a number of whole–part relationships, some of which, when instantiated, must use this symbol. It must be emphasized that this symbol represents links between instances (rather than relationships between types), and therefore can only be applied to objects and object facets of clabjects.

The symbol used to depict a whole–part link is an arc that goes from the symbol for the whole to the symbol for the part. The arc is a plain line with a white diamond-shaped arrow head on the end of the whole.

This symbol is identical to the “white-diamond ...