docs: void backupFile() {
  
          writeLock.lock();
  
          try {
              if (incBackup) {
                  if (fa.isStreamElement(backupFileName)) {
                      fa.removeElement(backupFileName);
                  }
  
                  return;
              }
  
              if (fa.isStreamElement(fileName)) {
                  FileArchiver.archive(fileName, backupFileName + ".new",
                                       database.getFileAccess(),
                                       FileArchiver.COMPRESSION_ZIP);
              }
          } catch (IOException e) {
              database.logger.appLog.logContext(e, null);
  
              throw new HsqlException(e.getMessage(), "", 0);
          } finally {
              writeLock.unlock();
          }
      }