resource relation

A Resource Relation is the relationship between a resource of a parent class and a resource of a child class.

• The resource of the parent class is referred to as the parent resource.
• The resource of the child class is referred to as the child resource.

Resource Relations can only exist between classes for which there is a class relation defined for the classes.

For a given class relation:

• There can exist 0 or more child resources for a parent resource
• There can exist 0 or 1 parent resources for a child resource

For example:

• Class relation between classes Supplier and Products, where Supplier is the parent class.
• Class Supplier has parent resource 'Supplier 1' which has resource relations to child resources 'Product A' and 'Product B' of child class Products.

  This also implies child resources 'Product A' and 'Product B' for child class Products both have parent resource 'Supplier 1' of parent class Supplier.

• Class Supplier has parent resource 'Supplier 2' which has no relations to resources of class Products.
• Class Products has resource 'Product X' which has no relations to resources of class Supplier.