code: protected void removeIndexBackup(String path) {
  
          if (!isBackupReindexing()) {
              // if no backup is generated we don't need to do anything
              return;
          }
  
          // check if the target directory already exists
          File file = new File(path);
          if (!file.exists()) {
              // index does not exist yet
              return;
          }
          try {
              FSDirectory dir = FSDirectory.open(file.toPath());
              dir.close();
              CmsFileUtil.purgeDirectory(file);
          } catch (Exception e) {
              LOG.error(Messages.get().getBundle().key(Messages.LOG_IO_INDEX_BACKUP_REMOVE_2, getName(), path), e);
          }
      }
docs: Removes the given backup folder of this index.<p>
  
  @param path the backup folder to remove