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

TestNG


JUnit and TestNG are two major Java testing frameworks. You already wrote tests with JUnit in the previous chapter, Chapter 3Red-Green-Refactor – From Failure Through Success until Perfection,  and, hopefully, got a good understanding of how it works. How about TestNG? It was born out of a desire to make JUnit better. Indeed, it contains some functionalities that JUnit doesn't have.

The following subsections summarize some of the differences between the two of them. We'll try not only to provide an explanation of the differences, but also their evaluation in the context of unit testing with TDD.

The @Test annotation

Both JUnit and TestNG use the @Test annotation to specify which method is considered to be a test. Unlike JUnit, which requires every method to be annotated with @Test, TestNG allows us to use this annotation on a class level, as well. When used in this way, all public methods are considered tests unless specified otherwise:

@Test
public class DirectionSpec {
  public void...