Step 2 - Zestâ„¢ "Making a booking."

Location: Page 17, "Knowledge-Rich Design.

Results from Step1

The ShippingServiceComposite

The ShippingServiceComposite declares which concerns should be used, and the order is significant. The SequencingConcern is placed first, that means it will be invoked before the OverbookingConcern, but it performs its own work after the call to the next.makeBooking() method.

The OverbookingConcern

It extends ConcernOf to show which MixinType it is chained into.

Moving on