code: public static Connection getConnection(String source) throws SQLException {
  		DataSource ds = getDataSource(source);
  		if (ds == null){
  			throw new SQLException("ConnectionUtility cannot get data source: " + source);
  		}
  		return ds.getConnection();
  	}
docs: 从指定的逻辑数据库源中获取数据库连接。
  @param source
  @return the database connection
  @throws SQLException