I read the posts in
- association owned by classifier and association owned by relationship in UML
- Setting the association end ownership in UML: What does it mean with respect to generated code in visual paradigm (or in other UML tools)?
- http://www.uml-diagrams.org/association.html
but the difference between "navigation" and "ownership" of associations of UML class diagrams is still unclear to me. Moreover, UML 2.5 was released in the meantime.
The specification states the following:
Association ends owned by classes are always navigable, while those owned by associations may be navigable or not.
This means, that the example c below is invalid. Examples a and b are valid, in both cases the right end is navigable. However, in example b the left end is not navigable.
Am I right?
What is the semantic difference between navigation and ownership? Is navigation a "generic" way of accessing the opposite class while ownership enforces a class to have an attribute?
