What you need for this book

We will be using Java 8 and Kotlin 1.1.50 for the programs in this book, so Oracle's JDK 1.8 along with Kotlin 1.1.50 (this can be skipped downloading if you're using IntelliJ IDEA) will be required. You will need an environment to write and compile your Kotlin code (I strongly recommend Intellij IDEA, but you can use anything of your choice), and preferably a build automation system such as Gradle or Maven. Later in this book, we will use Android Studio (2.3.3 or 3.0). Everything you need in this book should be free to use and not require commercial or personal licensing (we are using the IntelliJ IDEA Community Edition).