Memory leak in Kotlin companion objects?

Question

I'm using Kotlin for Android development. Interesting question. In Java saving Context in static field is a memory leak. But if I'm storing context in Kotlin companion object, Android Studio doesn't say that it's a memory leak. It's means that in Java bytecode conpanion object is not a static code? For example:

class MyApp : Application() {
    override fun onCreate() {
        super.onCreate()
        appContext = applicationContext
    }

    companion object {
        lateinit var appContext: Context
    }
}

Here is no memory leak? Thanks for answers :)

Answer 1

Your code does in fact store a Context in a static way, it's just that lint can't pick it up and warn you for some reason.

In this specific case, however, you're not really at risk of creating a memory leak. You're storing your Application object itself statically, which will be alive for the entirety of your application's life - just like static variables. You'd be in trouble if this was some other, shorter lived Context, but the application Context should be fine.

For reference about whether it's safe to do this:

• Is it safe to save the app context to a static variable in Android?
• Is it a bad practice to hold application Context instance?