Kotlin basics

Although Kotlin has a standalone compiler and can work with Eclipse, we are going to use IntelliJ IDEA.

A Kotlin project is structured much like a Java project. Following a standard Maven convention, you typically put your Kotlin source code in an src/main/kotlin/ folder instead of an src/main/java/ folder. The Kotlin source code is stored in text files with a .kt extension instead of .java. However, Kotlin files do not have to contain a class sharing the same name as the file.

Creating a Kotlin file

In IntelliJ IDEA, import your Kotlin project, if you haven't done so already. Right-click on the /src/main/kotlin/ folder and navigate to New | Kotlin File/Class, as shown in the following screenshot:

In the...