java.sql.SQLException: Access denied for user ‘Xs‘@‘localhost‘ (using password: YES) 出现的原因和解决办法

刚开始学jdbc时java连接数据库时出现报错：java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver 网上找找才知道：是在加载类的时候找不到该类，缺少对应的mysql-connector-java的jar包 在WEB-INF下创建了个文件夹lib放进mysql-connector-java-8.0.26.jar就不报这个错了，但是出现了java.sql.SQLException: Access denied for user 'Xs'@'localhost' (using password: YES)；的新报错！然后在找找的才知道原来之前用elicpise转到idea 有些配置变量名没改过来！在properties文件的用户变量名从elicpise的user变成了username 设置回来后就解决了！

 public static Connection getConnection() throws Exception{
        InputStream is = ClassLoader.getSystemClassLoader().getResourceAsStream("myjdbc.properties");
        Properties po = new Properties();
        po.load(is);
        String user = po.getProperty("username");
        String password = po.getProperty("password");
        String url = po.getProperty("url");
        String driverClass = po.getProperty("driverClassName");

        Class.forName(driverClass);

        Connection conn = DriverManager.getConnection(url, user, password);
        return conn;