code: public Connection createConnection(String url, String username, String password) throws SQLException {
  
  		if (connection != null && !connection.isClosed())
  			return connection;
  
  		connection = DriverManager.getConnection(url, username, password);
  		return connection;
  	}
docs: Constructs a new database connection object and retrieves it.
  
  @return The connection object.
  @throws SQLException