Data Classes

Data Classes

A data class is a class whose primary purpose is to hold data. Kotlin automatically generates toString, equals, copy, and more:

data class Point(val x: Int, val y: Int)

val p = Point(3, 4)
println(p)           // Point(x=3, y=4)
println(p.x)         // 3

The copy function creates a new instance with some values changed:

val q = p.copy(x = 10)
println(q)           // Point(x=10, y=4)

Data classes are perfect for representing immutable values like coordinates, records, or configuration.

Your Turn

Define a data class Person(val name: String, val age: Int). Create a person named "Alice" aged 30, print them, then create a copy with age 31 and print that.