Access Integer.class from Kotlin

Question

I have a Java method that accepts Class parameter. I need to pass Integer.class to it, but from Kotlin code. I tried Int::class.java, however this does not work, because int.class is passed to the function. My question is, how do I access Integer.class from Kotlin.

Java

void foo(Class clazz);

Kotlin

foo(Int::class.java) // does not work, int.class gets passed to foo

Answer 1

You must use the KClass#javaObjectType to get the wrapper type class in Kotlin:

Returns a Java Class instance corresponding to the given KClass instance. In case of primitive types it returns corresponding wrapper classes.

For example:

//                  v--- java.lang.Integer
println(Int::class.javaObjectType)

//                  v--- int
println(Int::class.java)