code: public void setCheckInterval(long checkInterval)
    {
      if (checkInterval < 0 || checkInterval > Long.MAX_VALUE / 2)
        _checkInterval = Long.MAX_VALUE / 2;
      else
        _checkInterval = checkInterval;
  
      _lastCheckTime = 0;
    }
docs: Sets the check modification check interval in milliseconds.
  Negative values mean never check. 0 means always check.
  
  @param checkInterval how often the dependency should be checked