Use Cases: Requirements in Context

by Daryl Kulak, Eamonn Guiney

Overview

This book describes how to gather and define software requirements using a process based on use cases. It shows systems analysts and designers how use cases can provide solutions to the most challenging requirements issues, resulting in effective, quality systems that meet the needs of users.

Use Cases, Second Edition: Requirements in Context describes a three-step method for establishing requirements—an iterative process that produces increasingly refined requirements. Drawing on their extensive, real-world experience, the authors offer a wealth of advice on use-case driven lifecycles, planning for change, and keeping on track. In addition, they include numerous detailed examples to illustrate practical applications.

This second edition incorporates the many advancements in use case methodology that have occurred over the past few years. Specifically, this new edition features major changes to the methodology's iterations, and the section on management reflects the faster-paced, more "chaordic" software lifecycles prominent today. In addition, the authors have included a new chapter on use case traceability issues and have revised the appendixes to show more clearly how use cases evolve.

The book opens with a brief introduction to use cases and the Unified Modeling Language (UML). It explains how use cases reduce the incidence of duplicate and inconsistent requirements, and how they facilitate the documentation process and communication among stakeholders.

The book shows you how to:

• Describe the context of relationships and interactions between actors and applications using use case diagrams and scenarios
• Specify functional and nonfunctional requirements
• Create the candidate use case list
• Break out detailed use cases and add detail to use case diagrams
• Add triggers, preconditions, basic course of events, and exceptions to use cases
• Manage the iterative/incremental use case driven project lifecycle
• Trace back to use cases, nonfunctionals, and business rules
• Avoid classic mistakes and pitfalls

The book also highlights numerous currently available tools, including use case name filters, the context matrix, user interface requirements, and the authors' own "hierarchy killer."

Product Details

ISBN-13:	9780133085150
Publisher:	Pearson Education
Publication date:	03/30/2012
Sold by:	Barnes & Noble
Format:	eBook
Pages:	272
File size:	18 MB
Note:	This product may take a few minutes to download.
Age Range:	18 Years

About the Author

Daryl Kulak is the president and CEO of Water-Logic Software (www.water-logic.com), an Internet business and technology consulting firm based in Columbus, Ohio. He is a graduate of the Northern Alberta Institute of Technology (NAIT) in Edmonton, Alberta. During much of his seventeen-year career managing software development projects in the United States and Canada, Daryl has focused on use cases, iterative/incremental development, and component design. Eamonn Guiney is a consultant at NewtonPartners (www.newtonpartners.com), a company that provides management consulting and system integration services to the money management industry. He is based in Sacramento, California. Eamonn creates business systems using a variety of tools, particularly object-oriented methodologies and use cases.

0321154983AB04012003

Read an Excerpt

PREFACE:

Use Cases: Requirements in Context came about, as most books probably do, as the result of a complaint. We felt that there weren't any good books that addressed use cases for requirements gathering. It seemed that a lot of people agreed that use cases were a perfectly good tool to solve the requirements problem, but no one had put down on paper any detailed process to help people understand how to use them this way. In fact, even as we write today, in late 1999, there is no book of this sort that we know of.

Requirements gathering has been a problem on almost every project we've been involved with. The fuzzy nature of requirements makes working with them slippery and unintuitive for most software analysts. Use cases are the first tool we've seen that addresses the specification and communication concerns usually associated with requirements gathering.

Although use cases in themselves are quite intuitive, the process around them is often done poorly. The questions that people have--How many iterations do I do? How fine-grained should a use case be?--are not answered or even addressed in most texts. This is probably because they are hard questions and the answers can vary greatly from one situation to another. However, they are important questions, and we decided to describe our own best practices as a first volley in what we hope will become a spirited industry dialog on how to generate requirements that will address user needs.

Use Cases: Requirements in Context is a practical book for the everyday practitioner. As consultants in the information technology industry, we employ use cases to specify business systems as part of ourdaily lives. We think we understand the issues facing people when they deliver software using tools such as the Unified Modeling Language and use cases. Our main intent is not to describe use case notation, although we do address that. Instead, we show a requirements process that addresses requirements gathering in a way that produces quality results.

While writing, we considered the factors that cause problems in requirements gathering, and we developed a use case method for delivering a requirements-oriented set of deliverables. The methodology breaks down the activity of producing requirements into a series of steps, and it answers the questions that usually come up when people employ use cases. This book relates directly to the real work of delivering a specification, managing that effort with a team, and getting the most bang for your buck.

The sample use cases and use case diagrams that appear throughout the book are also presented in Appendixes B and C. These appendixes demonstrate the development of the use cases and other requirements analysis artifacts through each phase of their development. Appendix B documents a business system for real estate, and Appendix C documents a business system for the garment industry.

We hope you enjoy this book. It was a labor of love for us. This is a process that works well for us. If it works for you, too, that's great. If it doesn't, perhaps you can adapt some of the tools, ideas, or suggestions to your own way of addressing the requirements problem.

0201657678P04062001

Table of Contents

• 1. The Trouble with Requirements.
• 2. Moving to Use Cases.
• 3. A Use-Case-Driven Approach to Requirements Gathering.
• 4. The Facade Iteration.
• 5. The Filled Iteration.
• 6. Focused Iteration.
• 7. Managing Requirements and People.
• 8. Requirements Traceability.
• 9. Classic Mistakes.
• 10. The Case for Use Cases.
• Bibliography.
• Index.
  

Preface

Use Cases: Requirements in Context came about, as most books probably do, as the result of a complaint. We felt that there weren't any good books that addressed use cases for requirements gathering. It seemed that a lot of people agreed that use cases were a perfectly good tool to solve the requirements problem, but no one had put down on paper any detailed process to help people understand how to use them this way. In fact, even as we write today, in late 1999, there is no book of this sort that we know of.

Requirements gathering has been a problem on almost every project we've been involved with. The fuzzy nature of requirements makes working with them slippery and unintuitive for most software analysts. Use cases are the first tool we've seen that addresses the specification and communication concerns usually associated with requirements gathering.

Although use cases in themselves are quite intuitive, the process around them is often done poorly. The questions that people have—How many iterations do I do? How fine-grained should a use case be?—are not answered or even addressed in most texts. This is probably because they are hard questions and the answers can vary greatly from one situation to another. However, they are important questions, and we decided to describe our own best practices as a first volley in what we hope will become a spirited industry dialog on how to generate requirements that will address user needs.

Use Cases: Requirements in Context is a practical book for the everyday practitioner. As consultants in the information technology industry, we employ use cases to specify businesssystems as part of our daily lives. We think we understand the issues facing people when they deliver software using tools such as the Unified Modeling Language and use cases. Our main intent is not to describe use case notation, although we do address that. Instead, we show a requirements process that addresses requirements gathering in a way that produces quality results.

While writing, we considered the factors that cause problems in requirements gathering, and we developed a use case method for delivering a requirements-oriented set of deliverables. The methodology breaks down the activity of producing requirements into a series of steps, and it answers the questions that usually come up when people employ use cases. This book relates directly to the real work of delivering a specification, managing that effort with a team, and getting the most bang for your buck.

The sample use cases and use case diagrams that appear throughout the book are also presented in Appendixes B and C. These appendixes demonstrate the development of the use cases and other requirements analysis artifacts through each phase of their development. Appendix B documents a business system for real estate, and Appendix C documents a business system for the garment industry.

We hope you enjoy this book. It was a labor of love for us. This is a process that works well for us. If it works for you, too, that's great. If it doesn't, perhaps you can adapt some of the tools, ideas, or suggestions to your own way of addressing the requirements problem.

Editorial Reviews

Describes how to gather and define software requirements using a process based on use cases. First examines difficulties of requirements gathering and introduces both use cases and UML. Presents detailed ongoing examples and a four-step method for establishing requirements, with practical advice provided on planning, scheduling, estimating, and common mistakes. Other tools examined include the stakeholder interview, team organization, and quality assurance. Kulak is president and CEO of an Internet business and technology consulting firm; Guiney works with a company that provides management consulting and system integration services. Annotation c. Book News, Inc., Portland, OR (booknews.com)

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