Hello, I’m trying to create a utility class that’s Java compatible. I was able in the past to do the...

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[Sami Eljabali]

Hello, I’m trying to create a utility class that’s Java compatible. I was able in the past to do the following:
Intents.kt

@file:JvmName("IntentsUtil")
@file:JvmMultifileClass

open class Intents {
    companion object
}

PlayStoreIntents.kt

@file:JvmName("IntentsUtil")
@file:JvmMultifileClass

fun Intents.Companion.viewAppOnPlayStore(appUri: String): Intent =
    Intent(Intent.ACTION_VIEW).apply {
        data = Uri.parse(appUri)
        setPackage(Apps.PLAY_STORE.url)
    }

When invoked Java side was able to simply:

IntentsUtil.viewAppOnPlayStore("foo");

Now however, it requires me to do:

IntentsUtil.viewAppOnPlayStore(Intents.Companion, "foo");

Any idea to why that is? How can I avoid passing the Companion object?

[nanodeath]

why is it an extension method?

[Sami Eljabali]

I have want to group different extension methods in different files. It would be too big of a mess to have them all in one file.

[rnett]

I would think this would work with JvmMultifileClass, but I'm guessing it doesn't play nice with companion objects. Can you make Intents an object? Probably worth filing a bug report

[Sami Eljabali]

I just tried using an object, and it just changed what I need to pass to the method:

IntentsUtil.viewAppOnPlayStore(Intents.INSTANCE, "foo");

[Sami Eljabali]

Good call, I’ll log a bug. It looks like a regression.

[Sami Eljabali]

https://youtrack.jetbrains.com/issue/KT-45811

[nanodeath]

"1.14.2"

did you mean 1.4.32?

[Sami Eljabali]

Updated. Thanks!

[Albert Chang]

I don't know why it worked before but I don't think this is supposed to work. You can see that @JvmStatic doesn't work on extensions. This makes sense because what if the extension is defined in a different module? I would say defining the utilities as top-level functions is a better choice.

[Sami Eljabali]

What if the extension is defined in a different module? What’s the worry there not following. Also can you elaborate how you would define these extensions?

[Albert Chang]

Modules are built independently. Assuming your Intents class is in module A, the compiled java class Intents.class is also in module A. Then you add an extension for Intents.Companion in module B, but it is impossible to insert the method into Intent.class which is compiled in module A.

[Sami Eljabali]

I don't see the problem. Don't we add extensions of classes built in entirely different modules/projects all the time?

[Albert Chang]

I’m saying that this is the reason you can’t make extensions static.

[rnett]

Yeah, I assume JvmMultifileClass won't work cross module. But if you're in the same module and using JvmMultifileClass, even across multiple files (which is what it's for), there's no reason JvmStatic wouldn't work. The whole point of JvmMultifileClass is to allow splitting a Java class across multiple files, so it's packing non-static methods into a single classfile already; static should be possible as well.

[rnett]

@Sami Eljabali it looks one solution is to use top-level functions in Kotlin with the JvmMultifileClass, see the example https://kotlinlang.org/docs/java-to-kotlin-interop.html#package-level-functions

I'd still think objects should be supported eventually, but idk if they are at the moment.