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Creating Java files in Kotlin projects

To create a java file in a kotlin project, follow these steps
  1. Create a Kotlin project as described in the sections Creating Kotlin-JVM Project or Creating Kotlin-JavaScript Project.
  2. In the Project tool window, select the target package or directory, where you want the Java class to be created.
  3. Press ⌘N, ⌃⏎, ⌘N or ⌃⏎⌃N, ⌃⏎, ⌃N or ⌃⏎⌘N, ⌃⏎, ⌘N or ⌃⏎^ N, ⌥ Insert, ⌃N or ⌃N⌥ Insert, choose Java Class from the pop-up menu, select its kind, and specify its name. See Creating Java Classes, Interfaces, Enumerations and Annotations.

Creating Kotlin files in Java projects

To create a kotlin file in a java project, follow these steps
  1. In a Java project, select the target location, press ⌘N, ⌃⏎, ⌘N or ⌃⏎⌃N, ⌃⏎, ⌃N or ⌃⏎⌘N, ⌃⏎, ⌘N or ⌃⏎^ N, ⌥ Insert, ⌃N or ⌃N⌥ Insert and choose Kotlin file from the pop-up menu.
  2. If this is first time you create a Kotlin file in a Java project, the banner shows:

    kotlin_banner

    Click the link Configure, and select the desired configurator:

    kotlin_configurator

    In the dialog box Create Kotlin Java Runtime Library that opens, do the following:

    • Choose the modules to configure (if there are several modules in a project)
    • Specify which Kotlin run-time library should be used.

    kotlin_runtime

    Note that in the future the configuration action is not required.