subtype polymorphism

Sometimes, of course, we want to use subtype polymorphism in our domain models. Longevity supports polymorphism in both your persistent objects and your persistent components. Polymorphism for components allows us to create and use controlled vocabularies in a standard Scala idiom. This chapter is broken up into the following pages:

• Polymorphic Components
• Polymorphic Persistents
• Controlled Vocabularies