code: private void setupModeOptions() {
  
          int versionsDeleted = OpenCms.getSystemInfo().getHistoryVersionsAfterDeletion();
  
          String mode;
  
          if (versionsDeleted == 0) {
              mode = CmsFileHistoryApp.MODE_DISABLED;
          } else if (versionsDeleted == 1) {
              mode = CmsFileHistoryApp.MODE_WITHOUTVERSIONS;
          } else if ((versionsDeleted > 1) || (versionsDeleted == -1)) {
              mode = CmsFileHistoryApp.MODE_WITHVERSIONS;
          } else {
              mode = CmsFileHistoryApp.MODE_DISABLED;
          }
          m_mode.setValue(mode);
      }
docs: Sets up the OptionGroup for the mode.<p>