Kotlin Help

Eclipse IDE

Eclipse IDE is a widely known IDE that offers various packages for development in different languages and for different platforms. You can use is for writing Kotlin code. On this page, you will learn how to get started with Kotlin in Eclipse IDE.

Set up the environment

First of all, you need the Eclipse IDE installed on your system. You can download its latest version from download page. The Eclipse IDE for Java Developers bundle is recommended.

To add the Kotlin support to your Eclipse IDE, install the Kotlin Plugin for Eclipse. We recommend installing the Kotlin plugin from Eclipse Marketplace. Open the Help | Eclipse Marketplace... menu and search for Kotlin Plugin for Eclipse:

Eclipse Marketplace

Once the plugin is installed and Eclipse is restarted, make sure the plugin is installed correctly: open the Kotlin perspective in the menu Window | Open Perspective | Other...

Kotlin Perspective

Create a new project

Now you are ready to create a new Kotlin project.

First, select File | New | Kotlin Project.

New Kotlin project

An empty Kotlin/JVM project will be created.

For Eclipse IDE, the project is also a Java project but configured with Kotlin nature, meaning it has the Kotlin Builder and reference to the Kotlin Runtime Library. Great thing about this solution is that you can add both Kotlin and Java code to the same project.

The project structure looks like this:

Empty Kotlin project

Now, create a new Kotlin file in the the source directory.

New file from context menu

You can enter the name without the .kt extension. Eclipse will add it automatically.

New Kotlin file wizard

Once you have a source file, add the main function - the entry point to a Kotlin application. You can simply type main and invoke code completion by hitting Ctrl + Space.

main() template

Finally, add a simple line of Kotlin code to print a message:

Hello World example

Run the application

To run the application, right-click somewhere in the main file and select Run As | Kotlin Application.

Run Kotlin application

If everything went well, you'll see the result in the Console window.

Program output view

Congratulations! You now have your Kotlin application running in Eclipse IDE.

Last modified: 28 May 2021