I have a data class:

@Parcelize
data class Task(
    var task: String,
    var done: Boolean = false
) : Parcelable

and corresponding type converters for my Room database:

object Converters {

    ...

    @TypeConverter
    fun tasksToJson(list: List<Task>): String {
        val objects = list.map { item ->
            val jsonObject = JSONObject()
            jsonObject.put("task", item.task)
            jsonObject.put("done", item.done)
        }
        return JSONArray(objects).toString()
    }

    @TypeConverter
    fun jsonToTasks(json: String): List<Task> {
        val iterable = JSONArray(json).iterable<JSONObject>()
        return iterable.map { jsonObject ->
            Task(jsonObject.getString("task"), jsonObject.getBoolean("done"))
        }
    }

    @Suppress("UNCHECKED_CAST")
    private fun <T> JSONArray.iterable(): Iterable<T> {
        return Iterable {
            object : Iterator<T> {
                var nextIndex = 0

                override fun next(): T {
                    val element = get(nextIndex)
                    nextIndex++
                    return element as T
                }

                override fun hasNext(): Boolean {
                    return nextIndex < length()
                }
            }
        }
    }
}

Everything is fine, but I wanna extend my data class so that each Task would have a sub task. This is how I extend the data class:

@Parcelize
data class Task(
    var task: String,
    var done: Boolean = false,
    var subTasks: List<Task> = emptyList() // -> sub tasks based on the same data class
) : Parcelable

So the question is now, if I need to extend the type converter for sub tasks too. If yes, how do I get it done? Thanks.