Interfaces

Discover Kotlin interfaces and define properties and methods for class implementation and conflicts in multi-interface scenarios.

Defining interfaces

An interface defines a set of properties and methods that a class should have. We define interfaces with the interface keyword, a name, and a body with the expected properties and methods.

Press + to interact
interface CoffeeMaker {
val type: String
fun makeCoffee(size: Size): Coffee
}

Implementing interfaces

When a class implements an interface, this class has to override all the elements defined by this interface.

Points to remember:

  • We can treat an instance of a class as an instance of an interface.

  • We implement interfaces similarly ...