Association and Property - some cases - with dot notation and ownership indicators

This slide shows the same Associations as the previous slide but with UML-Style dot notation activated using the Project Options in Magic Cyber-Systems Engineer^® (Cameo Systems Modeler^®):

Click on the image to view it full size

Some relevant quotes from the UML2.5.1 spec:

UML-2.5.1: 'Aggregation type, navigability, and end ownership are separate concepts, each with their own explicit notation. Association ends owned by classes are always navigable, while those owned by associations may be navigable or not.'

UML-2.5.1: 'Ownership of Association ends by an associated Classifier may be indicated graphically by a small filled circle, which for brevity we will term a dot. The dot is to be drawn integral to the graphic path of the line, at the point where it meets the Classifier, inserted between the end of the line and the side of the node representing the Classifier.'

UML-2.5.1: 'The dot shows that the model includes a Property of the type represented by the Classifier touched by the dot. This Property is owned by the Classifier at the other end.'

Note also that a Property may also exist alone without an Association. Visit also:

UML-2.5.1: 'A Property may represent an attribute of a Classifier, a memberEnd of an Association, or in some cases both simultaneously.'

SysMLv1: A part Property or reference Property is not necessarily a 'memberEnd' or 'ownedEnd' of an Association ('association' or 'owningAssociation'). But an Association always as at least 2 'memberEnd' Properties. [With some MagicDraw/Cameo tool tips.]

This optional dot notation from UML was dropped in "official" SysMLv1, but can be optionally activated in the Magic Cyber-Systems Engineer^® (Cameo Systems Modeler^®) and can be a useful learning aid.

You can test your understanding of some SysMLv1 cases here:

SysMLv1: Some invalid multiplicity examples with navigable and non-navigable Association ends. In Cameo Systems Modeler with validation.

Up next

InstanceSpecifications with links and Slots

Notes

[MODELLING, TIP]{INFORMATIVE} SysMLv1: MagicDraw/Cameo: Oh no, I lost my part or reference property? Where did it go? The Symbol Properties option for 'Show Association ends as Attributes' may help you find it!

Snippets (quotes/extracts)

[UML-2.5.1] A LiteralUnlimitedNatural specifies a constant value of the PrimitiveType UnlimitedNatural.

[UML-2.5.1] A LiteralUnlimitedNatural is shown either as a sequence of digits or as an asterisk (*), where an asterisk denotes unlimited.

[UML-2.5.1] A Property may represent an attribute of a Classifier, a memberEnd of an Association, or in some cases both simultaneously.

[SysML-1.7] SysML defines defaults for multiplicities on the ends of specific types of associations.

[SysML-1.7] A part or shared association has a default multiplicity of [0..1] on the black or white diamond end. A unidirectional association has a default multiplicity of 1 on its target end.