9.15. Example: Associations in the Domain Models
Case Study: NextGen POS
The domain model in Figure 9.17 shows a set of conceptual classes and associations that are candidates for our POS domain model. The associations are primarily derived from the "need-to-remember" criteria of this iteration requirements, and the Common Association List. Reading the list and mapping the examples to the diagram should explain the choices. For example:
- Transactions related to another transaction
Sale Paid-by CashPayment . - Line items of a transaction
Sale Contains SalesLineItem . - Product for a transaction (or line item)
SalesLineItem Records-sale-of Item .
Figure 9.17. NextGen POS partial domain model.
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Case Study: Monopoly
See Figure 9.18. Again, the associations are primarily derived from the "need-to-remember" criteria of this iteration requirements, and the Common Association List. For example:
- A is contained in or on B
Board Contains Square . - A owns B
Players Owns Piece . - A is known in/on B
Piece Is-on Square . - A is member of B
Player Member-of (or Plays) MonopolyGame .