Class-owned on both sides (explicitly navigable) - the ClassC class owns the attribute 'd' of the ClassD type and the ClassD class owns the attribute 'c' of the ClassC class.The association is navigable only in one direction from ClassA to ClassB. Class-owned on one side (navigable in one direction) - the ClassA class owns the attribute 'b' of the ClassB type.There are other possible combinations of association ends using the dot notation: UML associations with specified navigability and ownership The class ownership of the association end is depicted using the dot on the side of the class that owns the attribute (of the association end). The association is depicted as a connector with diagonal crosses on both sides.Īssociation Navigability with Class Ownership The non-navigable association expresses an indirect relationship between two classes which we want to emphasize in the model (e.g. In code, it means the fields representing this association are not defined in either of these two classes. Non-navigable - the association cannot be navigated in any direction, neither from Class9 to Class10 nor from Class10 to Class9.The association is depicted as a connector with a diagonal cross on one side and an arrow on the other side. This notation explicitly shows that the opposite navigation is not allowed. Navigable in one direction (explicit) - the association can be navigated from Class7 to Class8, but not from Class8 to Class7 (in a direct way).The association is depicted as a connector with arrows on both ends. In code, it means there is a field of the Class6 type defined within the Class5 class and a field of Class5 type defined within the Class6 class. Navigable in both directions - the association can be navigated from Class5 to Class6 and also from Class6 to Class5.The association is depicted as a connector with an arrow on one end. In code, it means there is a field of the Class4 type that is defined within the Class3 class. Navigable in one direction - the association can be navigated from Class3 to Class4, but not from Class4 to Class3 (in a direct way).The association is depicted as a simple undecorated connector. Unspecified navigability - there is an association between Class1 a Class2, but the navigability is unknown or irrelevant.The picture shows the following combinations of the navigability between associations: Various navigabilities of UML associations

Class diagram association