This is very interesting: ``` Class<PersonKotl...

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[poohbar]

This is very interesting:

Class<PersonKotlin> klass1 = PersonKotlin.class;
KClass<PersonKotlin> kotlinClass1 = JvmClassMappingKt.getKotlinClass(klass1);

Class<PersonJava> klass2 = PersonJava.class;
KClass<PersonKotlin> kotlinClass2 = JvmClassMappingKt.getKotlinClass(klass2);  // error

Although the types of klass1 and klass2 are identical the compiler recognizes that I can't call getKotlinClass on a Java class. How does it do that?

[dsavvinov]

It's not about Java/Kotlin. JvmClassMappingKt.getKotlinClass(klass2) returns KClass<PersonJava>, and you're assigning it to KClass<PersonKotlin> -- it's not "identical types", and they are not assignable to each other.

[poohbar]

yep, just found out now.. I am dumb.. Thanks!

[dsavvinov]

Np, that happens 🙂

[poohbar]

since you are here, so what does it mean to get a KClass of a java class? is it identical to a KClass from a kotlin class?

[poohbar]

i am surprised that I can pull constructor parameter names from a Java class using kotlin-reflect. I thought those would be only available with the -parameters flag.

[dsavvinov]

since you are here, so what does it mean to get a KClass of a java class? is it identical to a KClass from a kotlin class?

API-wise, it's the same. Of course, some of methods won't make sense for Java class -- then KClass will just fallback on some reasonable defaults (e.g. for isSealed it will return false)