Chapter 13 -- Implementing the Managers and Data Access

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Chapter 13

Your project has now advanced to the following state:

• In Chapter 10, "Implementing the Facades," you implemented the facade classes, using real code. As a result, the facade classes now access main business objects as they should, and they should be able to service the UI prototypes well. Because the main business objects are only test stubs, it's too early to subject your facades to intensive testing just yet. When you do, you'll probably find reasons to modify the code as well as the design. Still, if your requirement analysis has been effective, you have no reason to expect major modifications.
• In the same chapter, you took the test stubs originally made for the facades and moved them to your main business classes. The test stubs still don't access the database, but they act as if they do in a very limited way.
• Beginning with Chapter 12, "Delegating Data Access," your Rational Rose model now contains data access classes, not yet converted to code but designed to be able to manage all data access operations for their clients. All their clients are objects in the main business tier.

You're now able to repeat the same trick for the second time: generate code (this time for your data access classes), move the test stubs to the data access classes, and implement the main business classes with real code. The only thing left, then, is to implement the data access classes as well.

This time we won't go into as much detail as we did when we implemented the facade classes. The procedure is largely the same. But we'll show you some code examples in the HorseManager class as well as in its two data access classes.