docs: public static boolean isFormatCorrect(String fileName, ReadOnlyStorageFormat format) {
          switch(format) {
              case READONLY_V0:
              case READONLY_V1:
                  if(fileName.matches("^[\\d]+_[\\d]+\\.(data|index)")) {
                      return true;
                  } else {
                      return false;
                  }
  
              case READONLY_V2:
                  if(fileName.matches("^[\\d]+_[\\d]+_[\\d]+\\.(data|index)")) {
                      return true;
                  } else {
                      return false;
                  }
  
              default:
                  throw new VoldemortException("Format type not supported");
          }
      }