Chapter 8: Introducing Use-Case Diagrams

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Overview

In This Chapter

• Determining who will use your system

• Showing your system’s uses in terms of use cases

• Indicating system context

• Partitioning your system into use-case packages

UML has lots of pretty pictures and diagrams. Some focus on harnessing the power of object-oriented theory and techniques to analysis and design—and some focus on the meat-and-potatoes of detailed design and construction. In both cases, these diagrams help you accomplish a task or communicate with your peers in your organization.

However, practical development isn’t just an internal activity, especially in the current climate of competition and shrinking budgets. If you want to stay in business, you have to capture and understand your customer’s requirements and needs, and make a product or system that they want. Use cases and use-case diagrams are the UML features that support the gathering and analysis of user-centric requirements by starting with your users’ goals.

Use cases can keep you focused on your users’ goals and on producing practical systems that deliver value to your customers, whether they’re paying external customers or paying internal customers (those with the money inside your company).

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