July 2001
Beginner to intermediate
368 pages
6h 52m
English
book
Design Patterns Explained: A New Perspective on Object-Oriented Design
by Alan Shalloway, James R. Trott
Content preview from Design Patterns Explained: A New Perspective on Object-Oriented Design
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More Requirements for the Case Study
In the process of writing the application, suppose I get a new requirement to take the following actions whenever a new customer is entered into the system:
Send a welcome e-mail to the customer.
Verify the customer's address with the post office.
Are these all of the requirements? Will things change in the future?
If I am reasonably certain that I know every requirement, then I could solve the problem by hard-coding the notification behavior into the Customer class, such as shown in Figure 17-1.
Figure 17-1. Hard-coding the behaviors.
For example, using the same method that adds a new customer into the database, ...