Maybe a stupid question, but I've got quite a few companion objects, which need to be accessed from Java. Is there somehow a way to make all the functions is the companion objects JvmStatic by default, or, at least, put an annotation on the companion object or something? It would save me a ton of annotations.

There is no easy way to do it, but you can consider using top-level functions and top-level variables instead of companion objects. They looks nicer in Kotlin code and, at the same time, are automatically available as static methods from Java.

Thanks Roman. Appreciate it, but now I would like to rename the classname too. If I don't add anything, my classname is called NetworkKt.myStaticMethod(). But I'd like to call Network.myStatic(). I've tried adding @file:JvmName("Network") add the top of the file. but then IntelliJ can't find the class anymore. Any idea?

Try

@file:JvmName("Network")

You cannot have them in the same class if you have a class with the same name. I personally prefer

StuffKt

convention, but some people use

@file:JvmName

to rename it to

StuffUtil

or

Stuffs

.

Sorry, forgot to say that I tried both.

Here is the issue: https://youtrack.jetbrains.com/issue/KT-18664

Right. The thing is, I'm trying to convert a Java lib to Kotlin, and I'd like to keep the number of changes to a minimum. If I start introducing new classes, that's not great. I'll stick to the @JvmStatic for now, that solves the issue.

If you are trying to keep binary API of your existing Java lib, then companion objects with

@JvmStatic

is what you do, indeed.

Thanks for the link to the issue. I'm not 100% sure if it's the same, but it's very similar.

It is the issue. It will not compile when you have both

@file:JvmName("Network")

and

class Network(val name: String)

Thanks. I'll work my way around it, thanks (and no need to introduce statics into Kotlin, I think ;-)