How would you use UML to model multiple relationships between the same two classes?
Created May 14, 2012
John Moore
One way to show this is to simply use multiplicity on the relationship – an employee is "has" one or two addresses, as shown in the following class diagram:
But if it is important to show that one address is temporary and one is permanent, then a better way to model this would be to use two separate relationships with rolenames, as indicated below.
This second diagram would correspond more closely to the following code fragment:
public class Employee { private Address permanantAddress; private Address temporaryAddress; //... }
Note that this second approach is practical only when the maximum multiplicity is small.