The Cucumber for Java Book: Behaviour-Driven Development for Testers and Developers

325 Pages·2015·2.65 MB·English

by  Seb Rose

What Readers Are Saying About
The Cucumber for Java Book
This book is not just for programmers but for testers as well. It goes beyond using
Cucumber; it gives testing guidelines as well and hints and tips to avoid bad tests.
➤ Janet Gregory
Author, Agile Testing: A Practical Guide for Testers (with Lisa Crispin)
If you read this book in the morning, then find a stakeholder quickly enough,
you’ll be writing effective scenarios with that person in the afternoon. Start today.
➤ J.B. Rainsberger
Author, JUnit Recipes
The best thing about this book: it will help you identify WHY you may want to use
Cucumber, and it will guide you to good ways to do it in collaboration with your
whole team.
➤ Lisa Crispin
Author, Agile Testing: A Practical Guide for Testers (with Janet Gregory)
This is an excellent introduction to using Cucumber on the JVM that guides the
reader clearly through the complexities of the API and away from common pitfalls
in its application to real projects.
➤ Nat Pryce
Author, Growing OO Software Guided By Tests (with Steve Freeman)
Not only does [this book] go deep on the technical details of using Cucumber ef-
fectively in a Java environment, it also covers the broader issues of how to succeed
in driving software implementation through readable examples of system behavior,
and as such it will be a valuable reference for the whole team.
➤ David Evans
Author, Fifty Quick Ideas to Improve Your User Stories (with Gojko Adžić)
[If you] implement an application in a test-first manner, taking small and careful
steps and alternating implementation and refactoring phases, your tests will tell
you what to do next. So listen to your tests and listen to this book!
➤ Gáspár Nagy
Creator of SpecFlow - Cucumber for .NET
This book will teach you all you need to know to get started with Cucumber on
the Java platform...although the authors make sure that nonprogrammers can
follow along. It will find its place on my bookshelf and in the book recommendations
I give out in my training classes.
➤ Markus Gaertner
Author, ATDD by Example
This is a great reference guide for software project builds maintainers, because
the authors carefully address the integration of Cucumber with other Java platform
favorites such as JDBC, databases, dependency injection containers such as CDI
and Spring Framework, and REST server-side endpoints.
➤ Peter Pilgrim
Author, The Java EE 7 Developer Handbook
The Cucumber for Java Book meets an important need—the large Java community
has a great tool in Cucumber but very limited documentation on how to use it
effectively. This is the book I’ll recommend to my Java clients who want to hit the
ground running with Cucumber.
➤ Richard Lawrence
BDD Trainer and Coach, Agile for All
A gentle yet complete introduction to Cucumber on the JVM. An excellent step-
by-step guide with attention to detail.
➤ Paul Grenyer
Founder of Naked Element and NorDevCon
The material [in this book] is built on real-life experiences with appreciation for
the everyday problems we as testers/software architects/managers face both in-
ternally and externally.
➤ Márton Mészáros
Founder of Tailored Tunes and Test Automation Specialist
The authors get the combination of technical and nontechnical lessons across
very well. A very good read for the novice and experienced BDD follower alike.
➤ Craig Harrison
Software Engineer
The Cucumber for Java Book
Behaviour-Driven Development
for Testers and Developers
Seb Rose
Matt Wynne
Aslak Hellesøy
The Pragmatic Bookshelf
Dallas, Texas • Raleigh, North Carolina
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ISBN-13: 978-1-941222-29-4
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Book version: P1.0—February 2015
Contents
Foreword . . . . . . . . . . . . . . xi
Acknowledgments . . . . . . . . . . . xiii
Preface . . . . . . . . . . . . . . xv
Part I — Cucumber Fundamentals
1. Why Cucumber? . . . . . . . . . . . . 3
Automated Acceptance Tests 4
Behaviour-Driven Development 4
Living Documentation 6
How Cucumber Works 7
What We Just Learned 8
2. First Taste . . . . . . . . . . . . . 11
Understanding Our Goal 11
Creating a Feature 12
Creating Step Definitions 17
Implementing Our First Step Definition 19
Changing Cucumber’s Output 20
Testing Our Checkout Class 21
Adding an Assertion 23
Making It Pass 25
What We Just Learned 28
3. Gherkin Basics . . . . . . . . . . . . 31
What’s Gherkin For? 31
Format and Syntax 34
Feature 35
Scenario 36
Contents • viii
Comments 40
Spoken Languages 41
What We Just Learned 42
4. Step Definitions: From the Outside . . . . . . . 45
Steps and Step Definitions 46
Capturing Arguments 51
Multiple Captures 55
Flexibility 56
Returning Results 58
What We Just Learned 66
5. Expressive Scenarios . . . . . . . . . . 69
Background 69
Data Tables 72
Scenario Outline 79
Too Much Information 84
Doc Strings 86
Staying Organized with Tags and Subfolders 87
What We Just Learned 90
6. Keeping Your Cucumbers Sweet . . . . . . . . 91
Feeling the Pain 92
Working Together 95
Caring for Your Tests 102
Stop the Line and Defect Prevention 110
What We Just Learned 112
Part II — A Worked Example
7. Step Definitions: On the Inside . . . . . . . . 117
Sketching Out the Domain Model 118
Staying Honest with Transforms 123
Adding Custom Helper Methods 127
Organizing the Code 134
Dependency Injection 137
What We Just Learned 138
8. Support Code . . . . . . . . . . . . 141
Fixing the Bug 142
Bootstrapping the User Interface 149
Contents • ix
Making the Switch 151
Using Hooks 156
Getting to Green 160
What We Just Learned 166
9. Message Queues and Asynchronous Components . . . 169
Our New Asynchronous Architecture 169
How to Synchronize 170
Implementing the New Architecture 172
Fixing the Flickering Scenario 179
What We Just Learned 184
10. Databases . . . . . . . . . . . . . 185
Iterative Database Development 185
Refactoring to Use a Database 188
Reading and Writing to the Database 194
Cleaning the Database with Transactions 199
Cleaning the Database with Truncation 202
What We Just Learned 204
11. Simplifying Design with Dependency Injection . . . . 205
DI and Cucumber 205
Improving Our Design Using DI 207
PicoContainer Is Almost Invisible 213
Moving to Guice 214
Spring in Your Steps 218
CDI with Weld 221
What We Just Learned 223
12. Working with Web Applications . . . . . . . . 225
Selenium WebDriver 225
Handling Failure 228
Reusing the Browser 233
Ajax 235
What We Just Learned 242
13. Keeping Your Features Fast . . . . . . . . 245
Partitioning Features and Scenarios 245
What Sort of Tests? 248
Environment-Specific Step Definitions 250
Changing Step Definitions Using Tags 253
What We Just Learned 256