A simple consistency manager implementation on Kotlin.

ConsistencyManager.kt

interface ConsistencyManagerContract {
    fun notifyUpdateModel(model: Any)
    fun notifyUpdateClass(kclass: KClass<*>)
    fun subscribe(modelClass: KClass<*>, callback: WeakReference<(Any?) -> Unit>)
}

class ConsistencyManager : ConsistencyManagerContract {
    private val subscriptionsMap: MutableMap<KClass<*>, MutableList<WeakReference<(Any?) -> Unit>>> = mutableMapOf()

    override fun notifyUpdateModel(model: Any) {
        val kotlinClass = model.javaClass.kotlin

        subscriptionsMap[kotlinClass]?.forEach {
            it.get()?.invoke(model)
        }

    }

    override fun notifyUpdateClass(kclass: KClass<*>) {
        subscriptionsMap[kclass]?.forEach {
            it.get()?.invoke(null)
        }
    }

    override fun subscribe(modelClass: KClass<*>, callback: WeakReference<(Any?) -> Unit>) {
        var subscriptionsForModel = subscriptionsMap[modelClass]
        if (subscriptionsForModel == null) {
            subscriptionsForModel = mutableListOf(callback)
            subscriptionsMap.put(modelClass, subscriptionsForModel)
        } else {
            if (subscriptionsForModel.firstOrNull() { it.get() == callback.get() } == null) {
                subscriptionsForModel.add(callback)
            }
        }
    }


}