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 a /src/main/kotlin/ folder instead of a /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.