OkHttp3 IdlingResource in kotlin

OkHttp3IdlingResource.kt

class OkHttp3IdlingResource(
    private val name: String,
    private val dispatcher: Dispatcher
) : IdlingResource {

    private val callbackReference = AtomicReference<ResourceCallback>()

    init {
        dispatcher.idleCallback = Runnable {
            callbackReference.get()?.onTransitionToIdle()
        }
    }

    override fun getName(): String = name

    override fun isIdleNow(): Boolean {
        val isIdle = dispatcher.runningCallsCount() == 0
        val callback = callbackReference.get()
        if (isIdle && callback != null) callback.onTransitionToIdle()
        return isIdle
    }

    override fun registerIdleTransitionCallback(callback: ResourceCallback?) {
        callbackReference.set(callback)
    }
}