Kotlin - Composition with Delegation / Reflection - Two ways

Main.kt

import kotlin.reflect.KMutableProperty
import kotlin.reflect.KProperty
import kotlin.reflect.full.memberProperties

fun main() {

    // Create Sup
    val spiderman: SuperHeroe = SuperHeroe(Person(firstname = "Peter", lastname = "Parker", age = 28), "SpiderMan")

    println("Spiderman firstname: ${spiderman.firstname}")
    println("Spiderman lastname: ${spiderman.lastname}")
    println("Spiderman age: ${spiderman.age}")
    println("Spiderman supname: ${spiderman.supname}")
}

data class Person(
    var firstname: String,
    var lastname: String,
    var age: Int
) {
    inline operator fun <reified T> getValue(spiderman: SuperHeroe, property: KProperty<*>): T {
        val prop = this.javaClass.kotlin.memberProperties.find { it.name == property.name }
        if (prop != null) {
            return prop.get(this) as T
        }
        throw RuntimeException()
    }

    operator fun <T> setValue(spiderman: SuperHeroe, property: KProperty<*>, s: T) {
        // Recherche de la propriété
        val prop = this::class.members.find { it.name == property.name }
        // Set de la valeur
        if (prop is KMutableProperty<*>) {
            prop.setter.call(this, s)
        } else {
            throw RuntimeException()
        }
    }

    /**
     * Easy way without reflection matching properties
     */
    /*
    inline operator fun <reified T> getValue(o: Any, property: KProperty<*>): T {
        return when (property.name) {
            "firstName" -> this.firstname
            "lastName" -> this.lastname
            "age" -> this.age
            else -> throw RuntimeException()
        } as T
    }

    operator fun <T> setValue(o: Any, property: KProperty<*>, s: T) {
        when (property.name) {
            "firstName" -> this.firstname = s as String
            "lastName" -> this.lastname = s as String
            "age" -> this.age = s as Int
            else -> throw RuntimeException()
        }
    }
    */
}

data class SuperHeroe(
    var person: Person,
    var supname: String
) {
    var firstname: String by person
    var lastname: String by person
    var age: Int by person
}