code: @Implementation
    protected static boolean checkBluetoothAddress(String address) {
      if (address == null || address.length() != ADDRESS_LENGTH) {
        return false;
      }
      for (int i = 0; i < ADDRESS_LENGTH; i++) {
        char c = address.charAt(i);
        switch (i % 3) {
          case 0:
          case 1:
            if ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'F')) {
              // hex character, OK
              break;
            }
            return false;
          case 2:
            if (c == ':') {
              break; // OK
            }
            return false;
        }
      }
      return true;
    }
docs: Validate a Bluetooth address, such as "00:43:A8:23:10:F0" Alphabetic characters must be
  uppercase to be valid.
  
  @param address Bluetooth address as string
  @return true if the address is valid, false otherwise