char[] arr = str.toCharArray();
        time_low = hex_to_bin(arr, 0, 8);
        time_mid = S(hex_to_bin(arr, 9, 4));
        time_hi_and_version = S(hex_to_bin(arr, 14, 4));
        clock_seq_hi_and_reserved = B(hex_to_bin(arr, 19, 2));
        clock_seq_low = B(hex_to_bin(arr, 21, 2));
        node = new byte[6];
        node[0] = B(hex_to_bin(arr, 24, 2));
        node[1] = B(hex_to_bin(arr, 26, 2));
        node[2] = B(hex_to_bin(arr, 28, 2));

        char[] arr = str.toCharArray();
        this.time_low = hex_to_bin(arr, 0, 8);
        this.time_mid = S(hex_to_bin(arr, 9, 4));
        this.time_hi_and_version = S(hex_to_bin(arr, 14, 4));
        this.clock_seq_hi_and_reserved = B(hex_to_bin(arr, 19, 2));
        this.clock_seq_low = B(hex_to_bin(arr, 21, 2));
        this.node = new byte[6];
        this.node[ 0 ] = B(hex_to_bin(arr, 24, 2));