Migrating association roles in a class diagram

Chapter 3 Building Structural Diagrams

Migrating association roles in a class diagram

You can migrate association roles and create attributes before generation. This is very convenient for many reasons including data type customization and the ability to change the attribute order in the list of attributes. The last feature is especially important in XML.

Regardless of the navigability, the migration creates an attribute and sets its properties as follows:

Name and code of the attribute: association role if already set, if not the association name
Data type: code of the classifier linked by the association
Multiplicity: role multiplicity
Visibility: role visibility

Migration rules

The following rules apply when migrating association roles:

If the migrated attribute name is the same as the role name, then modifying the role name synchronizes the migrated attribute name
If the migrated attribute data type is the same as the role classifier, then modifying the role multiplicity synchronizes the migrated attribute multiplicity
If the code of the classifier, linked by the association, changes, then the migrated attribute data type is automatically synchronized
If you manually change the migrated attribute, the synchronization does not work, the association role is not synchronized
The migrated attribute is automatically deleted if the association is deleted

After migration, the property sheet of the new attribute displays the name of the association in the Migrated from box in the Detail tab.

Migrating navigable roles

You can migrate the navigable role of an association and turn it into an attribute:

To migrate navigable roles:

Right-click the association in the diagram.

Select Migrate→Migrate Navigable Roles from the association contextual menu.

An attribute is created and named after the navigable role of the association followed by the code of the classifier.