Kotlin Array isNotEmpty Function

The isNotEmpty function in Kotlin is used to check whether an array is not empty. This function is part of the Kotlin standard library and provides a straightforward way to determine if an array contains any elements.

Table of Contents

1. Introduction
2. isNotEmpty Function Syntax
3. Understanding isNotEmpty
4. Examples
   • Basic Usage
   • Using isNotEmpty with Custom Types
5. Real-World Use Case
6. Conclusion

Introduction

The isNotEmpty function returns a boolean value indicating whether the array has at least one element. It is a convenient method for checking if an array is not empty.

isNotEmpty Function Syntax

The syntax for the isNotEmpty function is as follows:

fun isNotEmpty(): Boolean

Parameters:

• This function does not take any parameters.

Returns:

• true if the array is not empty; false otherwise.

Understanding isNotEmpty

The isNotEmpty function is used to check if an array contains any elements. It is particularly useful in conditional statements where operations need to be performed only if the array is not empty.

Examples

Basic Usage

To demonstrate the basic usage of isNotEmpty, we will create an array of integers and check if it is not empty.

Example

fun main() {
    val emptyArray = emptyArray<Int>()
    val numbers = arrayOf(10, 20, 30, 40, 50)

    println("Is the empty array not empty? ${emptyArray.isNotEmpty()}")
    println("Is the numbers array not empty? ${numbers.isNotEmpty()}")
}

Output:

Is the empty array not empty? false
Is the numbers array not empty? true

Using isNotEmpty with Custom Types

This example shows how to use isNotEmpty to check if an array of custom objects is not empty.

Example

class Person(val name: String, val age: Int) {
    override fun toString(): String {
        return "Person(name='$name', age=$age)"
    }
}

fun main() {
    val emptyPeopleArray = emptyArray<Person>()
    val people = arrayOf(
        Person("Ravi", 25),
        Person("Anjali", 30),
        Person("Priya", 22)
    )

    println("Is the empty people array not empty? ${emptyPeopleArray.isNotEmpty()}")
    println("Is the people array not empty? ${people.isNotEmpty()}")
}

Output:

Is the empty people array not empty? false
Is the people array not empty? true

Real-World Use Case

Performing Operations Based on Array Contents

In real-world applications, the isNotEmpty function can be used to perform operations only if the array contains elements, such as processing a list of tasks.

Example

fun main() {
    val tasks = arrayOf("Task 1", "Task 2", "Task 3")

    if (tasks.isNotEmpty()) {
        tasks.forEach { task ->
            println("Performing task: $task")
        }
    } else {
        println("No tasks to perform.")
    }
}

Output:

Performing task: Task 1
Performing task: Task 2
Performing task: Task 3

Conclusion

The Array.isNotEmpty function in Kotlin is a convenient method for checking if an array contains any elements. It is particularly useful for conditional operations that depend on whether an array is not empty. By understanding and using this function, you can effectively manage array checks in your Kotlin applications.