Operator overloading concept in Kotlin - Mini Project: Build & Apply

Operator overloading concept

📖 Scenario: Imagine you have a simple Point in 2D space with x and y coordinates. You want to add two points together using the + operator, just like adding numbers.

🎯 Goal: Build a Kotlin class Point that supports adding two points using the + operator by overloading it.

📋 What You'll Learn

Create a class called Point with two Int properties: x and y

Create a variable called point1 with x = 2 and y = 3

Create a variable called point2 with x = 4 and y = 1

Add an operator function called plus inside Point to overload the + operator

Use the overloaded + operator to add point1 and point2 and store the result in result

Print the result point's x and y values

💡 Why This Matters

🌍 Real World

Operator overloading lets you use natural symbols like + or - with your own objects, making code easier to read and write, like adding points or complex numbers.

💼 Career

Understanding operator overloading is useful for Kotlin developers working on math libraries, games, graphics, or any domain where custom data types benefit from intuitive operations.

1

Create the Point class and two points

Create a class called Point with two Int properties: x and y. Then create two variables: point1 with x = 2 and y = 3, and point2 with x = 4 and y = 1.

Kotlin

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

// Create point1 and point2 below
// Your code here

Need a hint?

Use class Point(val x: Int, val y: Int) to create the class. Then create point1 and point2 as instances of Point.

2

Add operator function to overload +

Inside the Point class, add an operator function called plus that takes another Point as a parameter and returns a new Point with x and y added together.

Kotlin

class Point(val x: Int, val y: Int) {
    // Add operator function plus here
    // Your code here
}

val point1 = Point(2, 3)
val point2 = Point(4, 1)

Need a hint?

Use operator fun plus(other: Point): Point inside the class to overload the + operator.

3

Add two points using + operator

Create a variable called result that adds point1 and point2 using the + operator.

Kotlin

class Point(val x: Int, val y: Int) {
    operator fun plus(other: Point): Point {
        return Point(x + other.x, y + other.y)
    }
}

val point1 = Point(2, 3)
val point2 = Point(4, 1)

// Add point1 and point2 using + and store in result
// Your code here

Need a hint?

Use val result = point1 + point2 to add the two points with the overloaded operator.

4

Print the result point coordinates

Print the x and y values of the result point using println in the format: x = <value>, y = <value>.

Kotlin

class Point(val x: Int, val y: Int) {
    operator fun plus(other: Point): Point {
        return Point(x + other.x, y + other.y)
    }
}

val point1 = Point(2, 3)
val point2 = Point(4, 1)

val result = point1 + point2

// Print result coordinates
// Your code here

Need a hint?

Use println("x = ${result.x}, y = ${result.y}") to show the coordinates.