Writing Effective Use Cases (Crystal Series for Software Development) (Agile Software Development Series)

Writing use cases as a means of capturing the behavioral requirements of software systems and business processes is a practice that is quickly gaining popularity. Use cases provide a beneficial means of project planning because they clearly show how people will ultimately use the system being designed. On the surface, use cases appear to be a straightforward and simple concept. Faced with the task of writing a set of use cases, however, practitioners must ask:'How exactly am I supposed to write use cases?'Because use cases are essentially prose essays, this question is not easily answered, and as a result, the task can become formidable. In Writing Effective Use Cases, object technology expert Alistair Cockburn presents an up-to-date, practical guide to use case writing. The author borrows from his extensive experience in this realm, and expands on the classic treatments of use cases to provide software developers with a'nuts-and-bolts'tutorial for writing use cases. The book thoroughly covers introductory, intermediate, and advanced concepts, and is, therefore, appropriate for all knowledge levels. Illustrative writing examples of both good and bad use cases reinforce the author's instructions. In addition, the book contains helpful learning exercises--with answers--to illuminate the most important points. Highlights of the book include: A thorough discussion of the key elements of use cases--actors, stakeholders, design scope, scenarios, and more A use case style guide with action steps and suggested formats An extensive list of time-saving use case writing tips A helpful presentation of use case templates, with commentary on when and where they should be employed A proven methodology for taking advantage of use cases With this book as your guide, you will learn the essential elements of use case writing, improve your use case writing skills, and be well on your way to employing use cases effectively for your next development project. Contents Preface Acknowledgments Chapter 1 Introduction 1.1 What Is a Use Case (More or Less)? Use Case 1 Buy Stocks over the Web Use Case 2 Get Paid for Car Accident Use Case 3 Register Arrival of a Box 1.2 Your Use Case Is Not My Use Case Use Case 4 Buy Something (Casual Version) Use Case 5 Buy Something (Fully Dressed Version) Steve Adolph: “Discovering” Requirements in New Territory 1.3 Requirements and Use Cases Use Cases as Project-Linking Structure 1.4 When Use Cases Add Value 1.5 Manage Your Energy 1.6 Warm Up with a Usage Narrative Usage Narative: Getting “Fast Cash” 1.7 Exercises Part 1 The Use Case Body Parts Chapter 2 The Use Case as a Contract for Behavior 2.1 Interactions between Actors with Goals 2.2 Contract between Stakeholders with Interests 2.3 The Graphical Model Chapter 3 Scope 3.1 Functional Scope 3.2 Design Scope 3.3 The Outermost Use Cases 3.4 Using the Scope-Defining Work Products 3.5 Exercises Chapter 4 Stakeholders and Actors 4.1 Stakeholders 4.2 The Primary Actor 4.3 Supporting Actors 4.4 The System Under Discussion 4.5 Internal Actors and White-Box Use Cases 4.6 Exercises Chapter 5 Three Named Goal Levels 5.1 User Goals (Blue, Sea-Level) 5.2 Summary Level (White, Cloud/ Kite) 5.3 Subfunctions (Indigo/Black, Underwater/Clam) 5.4 Using Graphical Icons to Highlight Goal Levels 5.5 Finding the Right Goal Level 5.6 A Longer Writing Sample: “Handle a Claim” at Several Levels 5.7 Exercises Chapter 6 Preconditions, Triggers, and Guarantees 6.1 Preconditions 6.2 Minimal Guarantees 6.3 Success Guarantee 6.4 Triggers 6.5 Exercises Chapter 7 Scenarios and Steps 7.1 The Main Success Scenario 7.2 Action Steps 7.3 Exercises Chapter 8 Extensions 8.1 Extension Basics. 8.2 The Extension Conditions 8.3 Extension Handling 8.4 Exercises Chapter 9 Technology and Data Variations Chapter 10 Linking Use Cases 10.1 Sub Use Cases 10.2 Extension Use Cases 10.3 Exercises Chapter 11 Use Case Formats 11.1 Formats to Choose From 11.2 Forces Affecting Use Case Writing Styles 11.3 Standards for Five Project Types 11.4 Conclusion 11.5 Exercise Part 2 Frequently Discussed Topics Chapter 12 When Are We Done? Chapter 13 Scaling Up to Many Use Cases Chapter 14 CRUD and Parameterized Use Cases 14.1 CRUD Use Cases 14.2 Parameterized Use Cases Chapter 15 Business Process Modeling 15.1 Modeling versus Designing 15.2 Linking Business and System Use Cases Chapter 16 The Missing Requirements 16.1 Precision in Data Requirements 16.2 Cross-linking from Use Cases to Other Requirements Chapter 17 Use Cases in the Overall Process 17.1 Use Cases in Project Organization 17.2 Use Cases to Task or Feature Lists 17.3 Use Cases to Design 17.4 Use Cases to UI Design 17.5 Use Cases to Test Cases 17.6 The Actual Writing Chapter 18 Use Case Briefs and Extreme Programming Chapter 19 Mistakes Fixed 19.1 No System 19.2 No Primary Actor 19.3 Too Many User Interface Details 19.4 Very Low Goal Levels 19.5 Purpose and Content Not Aligned 19.6 Advanced Example of Too Much UI Part 3 Reminders for the Busy Chapter 20 Reminders for Each Use Case Reminder 1: A Use Case Is a Prose Essay Reminder 2: Make the Use Case Easy to Read Reminder 3: Just One Sentence Form Reminder 4: “Include” Sub Use Cases Reminder 5: Who Has the Ball? Reminder 6: Get the Goal Level Right Reminder 7: Keep the GUI Out Reminder 8: Two Endings Reminder 9: Stakeholders Need Guarantees Reminder 10: Preconditions Reminder 11: Pass/Fail Tests for One Use Case Chapter 21 Reminders for the Use Case Set Reminder 12: An Ever-Unfolding Story Reminder 13: Both Corporate Scope and System Scope Reminder 14: Core Values and Variations Reminder 15: Quality Questions across the Use Case Set Chapter 22 Reminders for Working on the Use Cases Reminder 16: It’s Just Chapter 3 (Where’s Chapter 4?) Reminder 17: Work Breadth First Reminder 18: The 12-Step Recipe Reminder 19: Know the Cost of Mistakes Reminder 20: Blue Jeans Preferred Reminder 21: Handle Failures Reminder 22: Job Titles Sooner and Later Reminder 23: Actors Play Roles Reminder 24: The Great Drawing Hoax Reminder 25: The Great Tool Debate Reminder 26: Project Planning Using Titles and Briefs Appendices Appendix A: Use Cases in UML A.1 Ellipses and Stick Figures A.2 UML’s Includes Relation A.3 UML’s Extends Relation A.4 UML’s Generalizes Relations A.5 Subordinate versus Sub Use Cases A.6 Drawing Use Case Diagrams A.7 Write Text-based Use Cases Instead Appendix B: Answers to (Some) Exercises Chapter 3, page 51 Chapter 4, page 60 Chapter 5, page 79 Chapter 6, page 85 Chapter 7, page 98 Chapter 8, page 110 Chapter 11, page 138 Appendix C: Glossary Main Terms Use Case Types Diagrams Appendix D: Readings Books Referenced in the Text Articles Referenced in the Text Useful Online Resources Index A B C D E F G H I J K L M N O P Q R S T U V W X Y

Writing use cases as a means of capturing the behavioral requirements of software systems and business processes is a practice that is quickly gaining popularity. Use cases provide a beneficial means of project planning because they clearly show how people will ultimately use the system being designed. On the surface, use cases appear to be a straightforward and simple concept. Faced with the task of writing a set of use cases, however, practitioners must ask: "How exactly am I supposed to write use cases?" Because use cases are essentially prose essays, this question is not easily answered, and as a result, the task can become formidable.

In Writing Effective Use Cases, object technology expert Alistair Cockburn presents an up-to-date, practical guide to use case writing. The author borrows from his extensive experience in this realm, and expands on the classic treatments of use cases to provide software developers with a "nuts-and-bolts" tutorial for writing use cases. The book thoroughly covers introductory, intermediate, and advanced concepts, and is, therefore, appropriate for all knowledge levels. Illustrative writing examples of both good and bad use cases reinforce the author's instructions. In addition, the book contains helpful learning exercises—with answers—to illuminate the most important points.

Highlights of the book include:

• A thorough discussion of the key elements of use cases—actors, stakeholders, design scope, scenarios, and more
• A use case style guide with action steps and suggested formats
• An extensive list of time-saving use case writing tips
• A helpful presentation of use case templates, with commentary on when and where they should be employed
• A proven methodology for taking advantage of use cases

With this book as your guide, you will learn the essential elements of use case writing, improve your use case writing skills, and be well on your way to employing use cases effectively for your next development project.

Booknews

A specialist in object technology presents software developers with a current guide to writing use cases as a means of capturing the behavioral requirements of software systems and business practices. Covers key elements of use cases, a style guide with suggested formats, a list of time-saving writing tips, a set of use case templates with commentary, and learning exercises with answers to clarify important points. Annotation c. Book News, Inc., Portland, OR (booknews.com)

Use cases have never been this easy to understand -- or this easy to create! In Writing Effective Use Cases , Alistair Cockburn offers a hands-on, soup-to-nuts guide to use case development, based on the proven concepts he has refined through years of research, development, and seminar presentations. Cockburn begins by answering the most basic questions facing anyone interested in use cases: "What does a use case look like? When do I write one?" Next, he introduces each key element of use cases: actors, stakeholders, design scope, goal levels, scenarios, and more. Writing Effective Use Cases contains detailed guidelines, formats, and project standards for creating use cases -- as well as a detailed chapter on style, containing specific do's and don'ts. Cockburn shows how use cases fit together with requirements gathering, business processing reengineering, and other key issues facing software professionals. The book includes practice exercises with solutions, as well as a detailed appendix on how to use these techniques with UML. For all application developers, object technology practitioners, software system designers, architects, and analysts. This guide will help readers learn how to employ the significant power of use cases to their software development efforts. It provides a practical methodology, presenting key use case concepts