Subsections

• 2.3.0.1 Relationship Ellipses
• 2.3.0.2 Annotation ellipses
  • 2.3.0.2.1 Ellipses in UML

  
2.3 Elided Diagrams

Elided diagrams are a shorthand for diagrams in order to avoid diagram cluttering. They allow information to be selectively and explicitly omitted. Such diagrams, in which information is explicitly omitted, are called elided diagrams.

2.3.0.1 Relationship Ellipses

 
Three types of relationship ellipses are defined: clientship ellipses, inheritance ellipses and import ellipses. The first indicates that a class or object has additional clientship relationships that are omitted on the diagram. Similarly, the second indicates that a class has further inheritance relationships in which it participates as a subclass that are omitted on the diagram. The third indicates that a module imports information from other modules, but the corresponding import relationships are not shown on the diagram.

2.3.0.2 Annotation ellipses

 
Annotation ellipses are used to indicate that an annotation only contains partial information. E.g., if a class has exactly two methods, this is indicated by the list method_1(), method_2(). If the class has more methods beside these two, this is indicated by method_1(), method_2(), .... Thus it is possible to derive from the diagram whether all the information has been included or whether some is missing. Because these annotations are optional, it is possible to indicate that there are no methods at all by using ().

Wherever information is missing, the reader of a diagram can quickly ascertain whether a particular diagram component is fully described (up to the limits of the notation by the systematic inclusion of relationship ellipses and annotation ellipses). In addition, a few rules are given in [AI95] to construct correct elided diagrams. This is important because it prohibits a wrong interpretation of the elided diagram with respect to the complete diagram.

2.3.0.2.1 Ellipses in UML

 
In UML, ellipses can also be used to indicate the existence of omitted elements. For example, the existence of additional subclasses may be shown by using an ellipsis (...) in place of a subclass. However, in UML the precise rules given in ION for the correct use of ellipses are missing.