code: @Nullable
    public static XMLGregorianCalendar getXMLCalendarTime (@Nullable final LocalTime aBase)
    {
      if (aBase == null)
        return null;
      return s_aDTFactory.newXMLGregorianCalendarTime (aBase.getHour (),
                                                       aBase.getMinute (),
                                                       aBase.getSecond (),
                                                       aBase.get (ChronoField.MILLI_OF_SECOND),
                                                       DatatypeConstants.FIELD_UNDEFINED);
    }
docs: Get the passed object as {@link XMLGregorianCalendar} time (without a
  date).
  
  @param aBase
  The source object. May be <code>null</code>.
  @return <code>null</code> if the parameter is <code>null</code>.