14.3. Delegation of Control
Not all state machines participate equally in the dynamics of a domain. In planning a system of more than a few state machines, we need to delegate responsibilities to the various state machines.
14.3.1. Hierarchical Delegation
Some state machines tell others what to do and get an immediate response. For example, the order tells the credit card charge to make a charge, and the order receives an immediate response indicating success or failure. Similarly, the shipment makes a request to the delivery company and receives a response first to assign a tracking number and then to confirm delivery. These examples of hierarchical control can be seen in Figure 14.8.
Figure 14.8. Bookstore Collaboration
14.3.2. Networked Delegation ...
Get Executable UML: A Foundation for Model-Driven Architecture now with the O’Reilly learning platform.
O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.
