kotlin collections EmptyMap Map Any Nothing io Serializable entries Set Entry keys serialVersionUID Long size Int values Collection containsKey Boolean key containsValue value equals other get hashCode isEmpty readResolve toString Stringp                   "BJ 2(8 HJ 2(8 HJ 2(8 HJ 2(8 HJ8HJ8 HJ8 HJ8 HR 8VHXR  8VHXR HXT ܛR 8VHXR 8VH XX 0 0 0 0 0 0 0 0 0 0 0 0 0 0