Hello, does anyone know the difference between `::...

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[Viet Hoang]

Hello, does anyone know the difference between ::class and .javaClass.kotlin ? And why is that in below example, the later declaration works but the prior doesn’t ?

class Test {
    fun testMethod() {
        this::class.memberProperties.forEach { println(it.get(this)) } // compile error 
        this.javaClass.kotlin.memberProperties.forEach { println(it.get(this)) }
    }

[alex2069]

I can't tell you why it's like this, but:
this::class is KClass<out Test>
Whereas this.javaClass.kotlin is KClass<Test>

[alex2069]

And if you go down the chain and look at each type explicitly:

val k1: KClass<out Test> = this::class
val m1: Collection<KProperty1<out Test, *>> = k1.memberProperties
val p1: KProperty1<out Test, *> = m1.first()

val k2: KClass<Test> = this.javaClass.kotlin
val m2: Collection<KProperty1<Test, *>> = k2.memberProperties
val p2: KProperty1<Test, *> = m2.first()

[alex2069]

I imagine it's because this::class could be this class or its inheritors

[alex2069]

Having said that - if the class is final then I would expect this::class to be KClass<Test>