Android Academy · Lesson

Data Classes

Concise classes for holding data.

What Is a Data Class?

A data class is a class made to hold data. Kotlin generates useful methods for it automatically.

You declare one by writing data before class.

A data class needs at least one parameter in its primary constructor, each marked val or var.

Here is a User that stores a name and an age.

data class User(val name: String, val age: Int)

fun main() {
    val u = User("Ada", 30)
    println(u.name)
}