That’s exactly what I’d expect. And that’s why I was surprised to see that the code in my first post (the Int::class.java variant) compiled fine and without any single warning and then failed at runtime. What’s funny, it fails at getProperty(), that is, it’s perfectly fine to store an int, but impossible to get it back because Integer cannot be cast to Int.
Come to think of, it… why? If Int is a Kotlin (not Java) class that corresponds to Java’s int, then why Class<Int>.cast() doesn’t work for values of type Integer? Is it just the way Java type system works? That is, Integer is not a subtype of Int, and that’s why the cast is impossible? And there’s no way to override that behavior because Class is still a type from Java standard library that works the way Java tells it to and there is no way to force it to be a little more gentle about such cross-language casts?
Or is it possible, just wasn’t done in Kotlin for some reason? For example, it would have undesirable side effects or break some important principles?