Visibility modifiers (public, private, internal, protected) in Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a public function named greet.

Kotlin

[1] fun greet() {
    println("Hello!")
}

Drag options to blanks, or click blank then click option'

Aprivate

Bpublic

Cinternal

Dprotected

Attempts:

3 left

💡 Hint

Common Mistakes

Using private or protected which restrict access.

Using internal which limits visibility to the module.

In Kotlin, functions are public by default, but explicitly using public makes it clear the function is accessible everywhere.

2fill in blank

medium

Complete the code to declare a private variable named secret.

Kotlin

class Vault {
    [1] val secret = "1234"
}

Drag options to blanks, or click blank then click option'

Aprivate

Bprotected

Cpublic

Dinternal

Attempts:

3 left

💡 Hint

Common Mistakes

Using public which exposes the variable everywhere.

Using internal which allows access within the module.

The private modifier restricts access to the variable within the class only.

3fill in blank

hard

Fix the error in the code by choosing the correct visibility modifier for the function.

Kotlin

open class Base {
    [1] fun show() {
        println("Base show")
    }
}

Drag options to blanks, or click blank then click option'

Aprivate

Binternal

Cprotected

Dpublic

Attempts:

3 left

💡 Hint

Common Mistakes

Using private which hides the function from subclasses.

Using internal which exposes it to the whole module.

The protected modifier allows the function to be visible in subclasses but not outside the class hierarchy.

4fill in blank

hard

Fill both blanks to declare an internal class with a private property.

Kotlin

[1] class Data {
    [2] val data = "hidden"
}

Drag options to blanks, or click blank then click option'

Ainternal

Bpublic

Cprivate

Dprotected

Attempts:

3 left

💡 Hint

Common Mistakes

Using public for the class which exposes it everywhere.

Using protected for the property, which allows access from subclasses.

The class is internal, so it is visible within the module. The property is private, so it is only accessible inside the class.

5fill in blank

hard

Fill all three blanks to declare a protected open class with an internal function and a public property.

Kotlin

class Outer {
    [1] open class MyClass {
        [2] fun internalFunc() {
            println("Internal function")
        }
        [3] val name = "Kotlin"
    }
}

Drag options to blanks, or click blank then click option'

Aprotected

Binternal

Cpublic

Dprivate

Attempts:

3 left

💡 Hint

Common Mistakes

Using private for the class, which hides it from subclasses.

Using public for the function which exposes it everywhere.

Using internal for the property which limits visibility.

The class is protected and open, so it can be subclassed and is visible to subclasses. The function is internal, visible within the module. The property is public, visible everywhere.