What is the best way to define log TAG constant in Kotlin?

Question

I\'m creating my first Kotlin classes in my Android application. Usually for logging purposes I have a constant with name TAG. What I would do in Java is:

Answer 1

Commonly suggested approach of using the companion object generates extra static final instance of a companion class and thus is bad performance and memory-wise.

The best way (IMHO)

Define a log tag as a top-level constant, thus only extra class is generated (MyClassKt), but compared to companion object there will be no static final instance of it (and no instance whatsoever):

private const val TAG = "MyLogTag"

class MyClass {

    fun logMe() {
        Log.w(TAG, "Message")
    }
}

Another option

Use a normal val. Though this looks unusual to see a log tag not as an all-uppercase constant, this will not generate any classes and has least overhead.

class MyClass {

    private val tag = "myLogTag"

    fun logMe() {
        Log.w(tag, "Message")
    }
}