second: Int, actual val minute: Int, actual val hour: Int, actual val dayOfMonth: Int, actual val monthOfYear: Int, actual val year: Int ) : Comparable<DateTime> { actual fun toDateFormatString(): String = DATE_FORMAT... override operator fun compareTo(other: DateTime): Int = compareValuesBy(this, other, ... actual operator fun plus(millis: Long): DateTime { val date = Date(year, monthOfYear, dayOfMonth, hour, minute, second) val newDate = Date(date.getUTCMilliseconds() + millis) return DateTime(newDate.getSeconds(), ...) } }