Kotlin - 6 - Operators in Kotlin

Operators are fundamental building blocks in programming languages like Kotlin. They enable you to perform operations on data, whether it’s mathematical calculations, comparisons, logical operations, or working with variables. Kotlin provides a comprehensive set of operators that make it easy to work with data of various types. In this guide, we’ll explore the most commonly used operators in Kotlin and demonstrate how they can be applied.

Arithmetic Operators

Arithmetic operators allow you to perform basic mathematical operations on numerical data types. Kotlin supports the following arithmetic operators:

+ (Addition)
- (Subtraction)
* (Multiplication)
/ (Division)
% (Modulus, remainder)

Here’s an example illustrating the use of arithmetic operators:

val a = 10
val b = 5

val sum = a + b // 15
val difference = a - b // 5
val product = a * b // 50
val quotient = a / b // 2
val remainder = a % b // 0

Comparison Operators

Comparison operators allow you to compare values and produce Boolean results. Kotlin supports the following comparison operators:

== (Equal to)
!= (Not equal to)
> (Greater than)
< (Less than)
>= (Greater than or equal to)
<= (Less than or equal to)

Here’s an example demonstrating comparison operators:

val x = 10
val y = 20

val isEqual = x == y // false
val isNotEqual = x != y // true
val isGreaterThan = x > y // false
val isLessThan = x < y // true
val isGreaterOrEqual = x >= y // false
val isLessOrEqual = x <= y // true

Logical Operators

Logical operators allow you to perform logical operations on Boolean values. Kotlin supports the following logical operators:

&& (Logical AND)
|| (Logical OR)
! (Logical NOT)

Here’s an example illustrating logical operators:

val isSunny = true
val isWindy = false

val andResult = isSunny && isWindy // false
val orResult = isSunny || isWindy // true
val notResult = !isSunny // false

Increment and Decrement Operators

Kotlin provides increment (++) and decrement (--) operators to increase or decrease the value of a variable by 1, respectively. These operators can be used with both var (mutable) and numeric variables.

var count = 5

count++ // Increment by 1 (count is now 6)
count-- // Decrement by 1 (count is now 5)

Assignment Operators

Assignment operators allow you to assign a value to a variable while simultaneously performing an operation. For example, the += operator adds a value to a variable and assigns the result back to the variable.

var total = 10

total += 5 // Equivalent to: total = total + 5 (total is now 15)

Elvis Operator

The Elvis operator (?:) is a convenient way to provide a default value when dealing with nullable variables. If the variable is not null, it returns the variable’s value; otherwise, it returns the specified default value.

val name: String? = null
val result = name ?: “Unknown” // “Unknown” because name is null

Command and Example

Here’s an example that demonstrates the use of various operators in Kotlin:

fun main() {
val a = 10
val b = 5
val isSunny = true

// Arithmetic Operators
val sum = a + b
val difference = a – b
val product = a * b
val quotient = a / b
val remainder = a % b

// Comparison Operators
val isEqual = a == b
val isNotEqual = a != b
val isGreaterThan = a > b
val isLessThan = a < b
val isGreaterOrEqual = a >= b
val isLessOrEqual = a <= b

// Logical Operators
val andResult = isSunny && isGreaterThan
val orResult = isSunny || isGreaterThan
val notResult = !isSunny

// Increment and Decrement Operators
var count = 5
count++
count–

// Assignment Operators
var total = 10
total += 5

// Elvis Operator
val name: String? = null
val result = name ?: “Unknown”

println(“Sum: $sum”)
println(“Difference: $difference”)
println(“Product: $product”)
println(“Quotient: $quotient”)
println(“Remainder: $remainder”)
println(“Is Equal: $isEqual”)
println(“Is Not Equal: $isNotEqual”)
println(“Is Greater Than: $isGreaterThan”)
println(“Is Less Than: $isLessThan”)
println(“Is Greater Or Equal: $isGreaterOrEqual”)
println(“Is Less Or Equal: $isLessOrEqual”)
println(“AND Result: $andResult”)
println(“OR Result: $orResult”)
println(“NOT Result: $notResult”)
println(“Count: $count”)
println(“Total: $total”)
println(“Result: $result”)
}

This example showcases the use of arithmetic, comparison, logical, increment/decrement, assignment, and Elvis operators in Kotlin. Understanding and mastering these operators is essential for effective programming in Kotlin and many other programming languages.

Kotlin – 6 – Operators in Kotlin