Sealed subclass without state and overridden equals

Reports direct inheritors of sealed classes that have no state and overridden equals() method.

It's highly recommended to override equals() to provide comparison stability, or convert the class to an object to reach the same effect.

Example:

  sealed class Receiver {
      class Everyone : Receiver()
      class User(val id: Int) : Receiver()
  }

The quick-fix converts a class into an object:

  sealed class Receiver {
      object Everyone : Receiver()
      class User(val id: Int) : Receiver()
  }

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

CanSealedSubClassBeObject

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | Kotlin | Probable bugs

Suppressing Inspection

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection CanSealedSubClassBeObject

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

IntelliJ IDEA 2025.2

Inspection Details
By default bundled with:	IntelliJ IDEA 2025.2, Qodana for JVM 2025.2,

Last modified: 18 September 2025