- Quick Review of Color and Class Archetypes
- Modeling Account Membership at a Simple Video Rental Business
Quick Review of Color and Class Archetypes
When modeling, we look for four categories of problem domain (PD) classes, the four class archetypes:
Moment/Interval (MI) (pink)A moment or interval in time that must be tracked for business or legal reasons.
Role (yellow)A role played by someone, something, or some place; a way of participating.
Party, Place, Thing (PPT) (green)A role player; a uniquely identifiable entity.
Description (Desc) (blue)A catalog-like entry; a set of values that apply again and again.
The archetypes suggest typical attributes and methods for their classes. The archetypes also suggest typical interactions between classes of different archetypes.
The Domain Neutral Component (DNC) is a pattern of archetypes that occurs again and again within PD object models of business systems (see Figure 1).
Figure 1 The Domain Neutral Component(DNC).