docs: @SuppressWarnings("unchecked")
      protected void initMessageObject() {
  
          try {
              if (CmsStringUtil.isEmpty(getParamAction()) || CmsDialog.DIALOG_INITIAL.equals(getParamAction())) {
                  // create a new list
                  m_groups = new ArrayList<String>();
              } else {
                  // this is not the initial call, get the message info object from session
                  m_groups = (List<String>)getDialogObject();
              }
          } catch (Exception e) {
              // create a new list
              m_groups = new ArrayList<String>();
          }
      }