I have a library written in Kotlin which is then u...

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[jcechace]

I have a library written in Kotlin which is then used as a dependency from Java code. Is it expected that KClass#primaryConstructor returns null?

[jcechace]

clazz.primaryConstructor!!.call(param)

When this line is executed from Kotlin code the primary consructor is returned. In Java I get a null value.

[wrongwrong]

I don't know if I understand your question, but for example, the following will cause the primaryConstructor to be null even in a Kotlin class.

import kotlin.reflect.full.primaryConstructor

class C {
    val v: Int

    constructor(v: Short) { this.v = v.toInt() }
}

fun main() {
    println(C::class.primaryConstructor) // -> null
}

The primaryConstructor will never be null for a data class.

[jcechace]

@wrongwrong I get that. In my case the class has primary constructor (its mandated by supertype). My issues is that with the ``primaryConstructor`` is when it’s accessed as part of Kotlin code base it’s there, when it’s from java it’s not… thinking about it… it makes perfect sense since Java classes probably don’t have a primary constructor :)… Thanks for being my rubber duck