To model an Association between two Model Elements, perform these steps:
1 Create an Association definition or an Association Class definition – either by creating the definition through the Explorer tree or drawing such a symbol on a diagram.
2 Draw an Association Node to Class as Property from the Association definition to an associated Classifier. Doing so creates a Property (or Port, which is a subtype of Property), which is a memberEnd of the Association.
You draw from the Association (or Association Class) to the class you want the property to reference.
You can set the type of ownership in the memberEnd property of the owning “works at” association.
3 Draw an Association Node to Class as Property from the Association definition to all other associated Classifiers.
When the relationship is drawn, the Association Node is made invisible.
In this example, drawing the association to the Company class specifies that you want to create a property in either the “works at” association or the Person class.
To specify that the association is navigable from the Class Company, and therefore that the class Company owns the property, you select the “employee” Property in the ownedAttribute property of the Class tab of the Company definition – drag-and-dropping it from the Choices list – it was created by drawing the Association Node to Class as Property relationship above.