docs: public boolean isValid(final int timeout) throws SQLException {
      if (timeout < 0) {
        throw new SQLException("the value supplied for timeout is negative");
      }
      if (isClosed()) {
        return false;
      }
  
      try {
        return protocol.isValid(timeout * 1000);
      } catch (SQLException e) {
        ExceptionMapper.checkConnectionException(e, this);
        return false;
      }
    }