Kotlin Standard Library Cookbook

Implementing delegated class properties

Class properties in Kotlin are more than just plain class fields. The key characteristic of Kotlin properties is the fact that their values are specified by accessor functions automatically. Each class property in Kotlin has a dedicated set of accessor functions available out of the box. By default, the Kotlin compiler generates a field storing the value of the property and its getters or setters as well. Each immutable val property has a corresponding get() function provided and the mutable one declared with var keyword has the set() function in addition to a get() as well. We are also able to override a default implementation of the accessor function, which makes a property highly customizable and ...