Guys, I have a very weird Java / Kotlin interoperability problem with the

Boolean

type. I’m using a Java API which defines two functions:

void setSomething(boolean enabled)

and

void setSomething(Boolean enabled)

, where

Boolean

is

java.lang.Boolean

here. The first function with the primitive Java type is marked deprecated. I’m trying to call the second function from Kotlin code but every time Kotlin tries to unbox the boolean into the primitive type, so it calls the deprecated function. How can I force Kotlin to use the boxed object type? For example I tried

api.setSomething(Boolean.valueOf(true))

but it’s still complaining.

Just a guess, but maybe

true as java.lang.Boolean

?

Unfortunately not, this gives a type error

Required: kotlin.Boolean
Found: java.lang.Boolean

Maybe

true as Boolean?

?

Yes, that’s it! Thank you!

It’s worth keeping in mind that Kotlin/JVM treats

Boolean

as the unboxed

boolean

primitive and

Boolean?

as the boxed

java.lang.Boolean

(see here). Similarly to numbers.