It's tempting at this point in the book to dive into the Groovy language. Instead in this chapter we will take a slightly different tack. Here we will take a look at two essential Groovy tools and, more importantly, the DSLs that they provide. Gradle is a build, test and deployment automation tool, which is powered by a Groovy DSL. Spock is a unit testing and specification framework built over JUnit. The stand out feature of Spock is its highly expressive Groovy based DSL, which allows the tests to be written in behavior-driver development (BDD) style semantics.

In this chapter we will cover some of the basic features of both DSLs. Both Gradle and Spock are used extensively in the code examples that accompany this book. Where possible throughout the rest of the book we will use Spock's BDD syntax to illustrate Groovy features. I urge you to read this chapter first before continuing with the rest of the book. Familiarity with Spock and Gradle will be assumed...