code: private static Connection doConnect(String driver, String url, String username, String password) throws SQLException, ClassNotFoundException {
          Class.forName(driver);
          Connection connection = DriverManager.getConnection(url, username, password);
          logger.debug("DB Connected Successfully");
          return  connection;
      }
docs: This will attempt to connect to a database using
  the provided parameters.
  On success it'll return the java.sql.Connection object
  @param driver the class name for the mysql driver to use
  @param url the url of the database
  @param username database username
  @param password database password
  @return Connection
  @throws SQLException exception
  @throws ClassNotFoundException exception