First Program in Kotlin using IntelliJ IDEA

In the last tutorial, we saw how to install IntelliJ idea in our system. In this tutorial, we will see how to create a new project in IntelliJ IDEA IDE and run our first program in Kotlin which will print "Hello World" on the console.

Create a new project in IntelliJ IDEA

Setting up a project in IntelliJ is necessary to run any Kotlin file. Follow these steps to create a new project:

• Go to start, search IntelliJ IDEA, and open it. If you are running it the first time you might see some first-time settings like import settings and select a dark or normal theme. Choose it accordingly.

• Next, you'll see this window:
  

• Click on "Create New Project".

• Choose Kotlin from the left side panel and select "JVM| IDEA" option. Click on next.
  

• Enter the name of the project. You can edit the project location and provide a custom location.
  

• On the left side, you can see the project structure like this:
  

• Right click on src folder and select New > Kotlin File/Class and hit enter. You’ll see:
  

• Enter file name "HelloWorld" and hit enter.

You have successfully created a new Kotlin project and a Kotlin file in it. Now we'll create our first Kotlin program in it.

First program in Kotlin

Write the following program is HelloWorld.kt file:

fun main() {
    println("Hello World")
}

Explanation:

• Line 1: Every Kotlin program starts with the main() function. Functions are created using the fun keyword in Kotlin. We'll read more about functions in later sections.

• Line 2: println() function is used to print strings on the console.

To run this program click on the green arrow just beside main() function as shown here:

The program will be compiled and output will be printed on the console:

Summary

In this article, we created a Kotlin project and run our first program in Kotlin. In the next tutorial, we see how to run the same program through the command line.