How to access Kotlin companion objects from Java

Question

I have this Kotlin class:

class Storage {
    companion object {
        val COL_ID = "id"
    }
}

and I want to use the COL_ID in my Java code:

doSomething(Storage.COL_ID);

but, the compiler tells me that COL_ID is private. I have tried to add public to all the elements (class, object and val), but it has no effect.

How can I access these companion object constants?

Update I think my question is different from the given duplicate, because I want to create constants, instead of a static method.

Io

You are missing const from your const val COL_ID (or @JvmField) – Aldershot

@Aldershot that simple ... – Io

Possible duplicate of How to access Kotlin companion object in Java? – Schecter

@Steve no, it finds it, it just was not accesible. – Io

Hmmm...I wouldn't think that would work. Ok, well, I don't understand it then. So what was the solution you ultimately came up with? You said you already tried making it 'public' – Schecter

I'm new to Kotlin, so I'd really like to understand your soluton. All I can make work in my own IDE is: Storage.Companion.getCOL_ID() unless I add the @JvmStatic annotation – Schecter

@Steve see my updated question and answer. – Io

@BartFriederichs - cool. I'm still at a loss for what's going on here, as I don't see why making this 'const' would change how it is referenced. Do you have any insight into that? - +1'd your answer btw. – Schecter

@Steve See discuss.kotlinlang.org/t/why-does-kotlin-need-const-keyword/…. – Tsarism

Answer 1

I added const, and everything was fine:

class Storage {
    companion object {
        const val COL_ID = "id"
    }
}

Io