code: @Nonnull
    public static EValidity validateMessage (@Nullable final String sMsg)
    {
      final int nLen = StringHelper.getLength (sMsg);
      if (nLen >= 7 && nLen <= 8)
        if (AbstractUPCEAN.validateMessage (sMsg).isValid ())
          return EValidity.VALID;
      return EValidity.INVALID;
    }
docs: Validates a EAN-8 message. The method throws IllegalArgumentExceptions if
  an invalid message is passed.
  
  @param sMsg
  the message to validate
  @return {@link EValidity#VALID} if the msg is valid,
  {@link EValidity#INVALID} otherwise.