Can primitive types be used in Kotlin?

Yes, it is possible. Kotlin supports primitive types, but they are represented as object wrappers.

For example:

• Int instead of int
• Boolean instead of boolean

When compiling Kotlin code for JVM, these object wrappers can be optimized down to native primitives for performance (e.g., when used in local variables).

fun main() {
    val count: Int = 10 // Uses the Int wrapper
    val isActive: Boolean = true // Uses the Boolean wrapper
    println(count)
    println(isActive)
}

Interaction with Java is seamless: Java primitive types are automatically converted to Kotlin wrappers and vice versa.

// Java code
public class JavaClass {
    public static int getIntValue() {
        return 5;
    }
}

// Kotlin code
import JavaClass

fun main() {
    val value: Int = JavaClass.getIntValue() // Java int is converted to Kotlin Int
    println(value)
}