code: @Override
      public void executeListMultiActions() throws CmsRuntimeException {
  
          if (getParamListAction().equals(LIST_MACTION_DELETE)) {
              // execute the delete multiaction
              List<String> removedItems = new ArrayList<String>();
              Iterator<CmsListItem> itItems = getSelectedItems().iterator();
              while (itItems.hasNext()) {
                  CmsListItem listItem = itItems.next();
                  try {
                      OpenCms.getScheduleManager().unscheduleJob(getCms(), listItem.getId());
                      removedItems.add(listItem.getId());
                  } catch (CmsException e) {
                      throw new CmsRuntimeException(
                          Messages.get().container(Messages.ERR_UNSCHEDULE_JOB_1, listItem.getId()),
                          e);
                  }
              }
              // update the XML configuration
              writeConfiguration(false);
          } else if (getParamListAction().equals(LIST_MACTION_ACTIVATE)
              || getParamListAction().equals(LIST_MACTION_DEACTIVATE)) {
              // execute the activate or deactivate multiaction
              Iterator<CmsListItem> itItems = getSelectedItems().iterator();
              boolean activate = getParamListAction().equals(LIST_MACTION_ACTIVATE);
              while (itItems.hasNext()) {
                  // toggle the active state of the selected item(s)
                  CmsListItem listItem = itItems.next();
                  try {
                      CmsScheduledJobInfo job = (CmsScheduledJobInfo)OpenCms.getScheduleManager().getJob(
                          listItem.getId()).clone();
                      job.setActive(activate);
                      OpenCms.getScheduleManager().scheduleJob(getCms(), job);
                  } catch (CmsException e) {
                      throw new CmsRuntimeException(
                          Messages.get().container(Messages.ERR_SCHEDULE_JOB_1, listItem.getId()),
                          e);
                  }
              }
              // update the XML configuration
              writeConfiguration(true);
          } else {
              throwListUnsupportedActionException();
          }
          listSave();
      }
docs: This method should handle every defined list multi action,
  by comparing <code>{@link #getParamListAction()}</code> with the id
  of the action to execute.<p>
  
  @throws CmsRuntimeException to signal that an action is not supported