Book Image

Test-Driven Java Development, Second Edition - Second Edition

By : Viktor Farcic, Alex Garcia
Book Image

Test-Driven Java Development, Second Edition - Second Edition

By: Viktor Farcic, Alex Garcia

Overview of this book

Test-driven development (TDD) is a development approach that relies on a test-first procedure that emphasizes writing a test before writing the necessary code, and then refactoring the code to optimize it.The value of performing TDD with Java, one of the longest established programming languages, is to improve the productivity of programmers and the maintainability and performance of code, and develop a deeper understanding of the language and how to employ it effectively. Starting with the basics of TDD and understanding why its adoption is beneficial, this book will take you from the first steps of TDD with Java until you are confident enough to embrace the practice in your day-to-day routine.You'll be guided through setting up tools, frameworks, and the environment you need, and we will dive right into hands-on exercises with the goal of mastering one practice, tool, or framework at a time. You'll learn about the Red-Green-Refactor procedure, how to write unit tests, and how to use them as executable documentation.With this book, you'll also discover how to design simple and easily maintainable code, work with mocks, utilize behavior-driven development, refactor old legacy code, and release a half-finished feature to production with feature toggles.You will finish this book with a deep understanding of the test-driven development methodology and the confidence to apply it to application programming with Java.
Table of Contents (18 chapters)
Title Page
Packt Upsell
Contributors
Preface
9
Refactoring Legacy Code – Making It Young Again
Index

The TDD or test-first implementation


At this time, we know how TDD works—writing tests before, implementation after tests, and refactoring later on. We are going to pass through the process and only show the final result for each requirement. It is left to you to figure out the iterative Red-Green-Refactor process. Let's make this more interesting, if possible, by using a Hamcrest framework in our tests.

Hamcrest

As described in Chapter 2, Tools, Frameworks, and Environment, Hamcrest improves our test's readability. It makes assertions more semantic and comprehensive when complexity is reduced by using matchers. When a test fails, the error shown becomes more expressive by interpreting the matchers used in the assertion. A message could also be added by the developer.

The Hamcrest library is full of different matchers for different object types and collections. Let's start coding and get a taste of it.

Requirement 1 – the game's board

We will start with the first requirement.

Note

The board is...