MDA Distilled: Principles of Model-Driven Architecture

Subject Matter and Language Abstraction

Figure 3-2 shows some of the conceptual entities associated with a banking system, which we have abstracted, classified, and generalized by examining “real” customers, accounts, and transactions and capturing their critical properties, such as customer city, account balance, and transaction amount. In so doing, our modeler has abstracted away irrelevant properties, such as a customer's salary, number of children, and ghastly personal habits. However, the model also has abstracted away information that's required to make the system work properly, such as how we know that Fred (an object of class Customer) truly is Fred when he attempts to withdraw money from his account.

Figure 3-2. Domain-level class diagram ...