docs: public void doAdd(@FormGroup("dataMediaInfo") Group dataMediaInfo,
                        @FormField(name = "formDataMediaError", group = "dataMediaInfo") CustomErrors err, Navigator nav)
                                                                                                                         throws Exception {
  
          DataMedia dataMedia = new DataMedia();
          dataMediaInfo.setProperties(dataMedia);
          DataMediaSource dataMediaSource = dataMediaSourceService.findById(dataMediaInfo.getField("sourceId").getLongValue());
          if (dataMediaSource.getType().isMysql() || dataMediaSource.getType().isOracle()) {
              dataMedia.setSource((DbMediaSource) dataMediaSource);
          } else if (dataMediaSource.getType().isNapoli() || dataMediaSource.getType().isMq()) {
              dataMedia.setSource((MqMediaSource) dataMediaSource);
          }
  
          try {
              dataMediaService.create(dataMedia);
          } catch (RepeatConfigureException rce) {
              err.setMessage("invalidDataMedia");
              return;
          }
  
          nav.redirectTo(WebConstant.DATA_MEDIA_LIST_LINK);
      }