IntelliJ IDEA 2021.2 Help

Run/Debug Configuration: Kotlin

The Kotlin run/debug configuration enables you running or debugging Kotlin applications.

Configuration tab



Main class

Specify the fully qualified name of the class to be executed (passed to the JRE). Type the class name manually or click the Browse button to open the Choose Main Class dialog, where you can find the desired class by name or search through the project.

VM options

Specify the string to be passed to the VM for launching an application, for example, -mx, -verbose, and so on.

When specifying JVM options, follow these rules:

  • Use spaces to separate individual options, for example, -client -ea -Xmx1024m.

  • If an option includes spaces, enclose the spaces or the argument that contains spaces in double quotes, for example, some" "arg or "some arg".

  • If an option includes double quotes (as part of the argument), escape the double quotes using backslashes, for example, -Dmy.prop=\"quoted_value\".

  • You can pass environment variable values to custom Java properties. For example, if you define a variable MY_ENV_VAR, you can pass it to the foo property as follows:


The -classpath option specified in this field overrides the classpath of the module.

Program arguments

Type a list of arguments to be passed to the program in the format you would use on the command line. Use the same rules as for specifying the VM options.

Working directory

Specify the working directory to be used for running the application. This directory is the starting point for all relative input and output paths. By default, the field contains the directory where the project file resides. To specify another directory, click the Browse button and select the directory.

Expand the list to view available path variables that you can use as a path to your working directory.

Environment variables

Create environment variables and specify their values.

Redirect input from

Specify a file to read the input from. Relative paths are prepended with the Working directory path.

Macros (Icons general add dark) and path variables are also available in this field.

Use classpath of module

Select the module whose classpath should be used to run the application.

Add dependencies with “provided” scope to classpath

Enable this option to add dependencies with the Provided scope to the runtime classpath.

Shorten command line

Select a method that will be used to shorten the command line if the classpath gets too long, or you have many VM arguments that exceed your OS command line length limitation:

  • none: IntelliJ IDEA will not shorten a long classpath. If the command line exceeds the OS limitation, IntelliJ IDEA will be unable to run your application and will display a message suggesting you to specify the shortening method.

  • JAR manifest: IntelliJ IDEA will pass a long classpath via a temporary classpath.jar. The original classpath is defined in the manifest file as a class-path attribute in classpath.jar. You will be able to preview the full command line if it was shortened using this method, not just the classpath of the temporary classpath.jar.

  • classpath file: IntelliJ IDEA will write a long classpath into a text file.


By default, the newest JDK from the module dependencies is used to run the application. If you want to specify an alternative JDK or JRE here, select it from the list.

Last modified: 02 August 2022