docs: public void addUploadedFile (@Nonnull @Nonempty final String sFieldName, @Nonnull final TemporaryUserDataObject aUDO)
    {
      ValueEnforcer.notEmpty (sFieldName, "FieldName");
      ValueEnforcer.notNull (aUDO, "UDO");
  
      m_aRWLock.writeLocked ( () -> {
        // Remove an eventually existing old UDO with the same filename - avoid
        // bloating the list
        final TemporaryUserDataObject aOldUDO = m_aMap.remove (sFieldName);
        if (aOldUDO != null)
          _deleteUDO (aOldUDO);
  
        // Add the new one
        m_aMap.put (sFieldName, aUDO);
      });
    }