如果代码写的没有问题，报各种奇怪的错误，尝试升级版本解决。在Mac上测试使用druid连接池获取连接时，报如下错误：Loadingclass`com.mysql.jdbc.Driver'。这已被弃用。新的驱动程序类是“com.mysql.cj.jdbc.Driver”。驱动程序通过SPI自动注册，通常不需要手动加载驱动程序类。2021年11月17日10:00:03下午com.alibaba.druid.pool.vendor.MySqlValidConnectionChecker警告：无法解析com.mysq.jdbc.Connection.ping方法。将在com.alibaba.druid.pool.vendor.MySqlValidConnectionChecker.(MySqlValidConnectionChecker.java:48)在com.alibaba.druid.pool.DruidDataSource.initValidConnectionChecker(DruidDataSource)处使用“SELECT1”.java:878)在com.alibaba.druid.pool.DruidDataSource.init(DruidDataSource.java:594)在com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:915)在com.alibaba.druid。pool.DruidDataSource.getConnection(DruidDataSource.java:911)在com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:98)atcn.itcast.util.JDBCUtils.getConnection(JDBCUtils.java:34)atcn.itcast.jdbc.DruidDemo.main(DruidDemo.java:10)十一月17,202110:00:05下午com.alibaba.druid.pool.DruidDataSourceerror严重：initdatasourceerrorjava.sql.SQLException:validateConnectionfalseatcom.alibaba.druid.pool.DruidAbstractDataSource.validateConnection(DruidAbstractDataSource.java:1216)atcom.alibaba.druid.pool.DruidAbstractDataSource.createPhysicalConnection(DruidAbstractDataSource.java:1439)在com.alibaba.druid.pool.DruidDataSource.init(DruidDataSource.java:618)在com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:915)在com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:911)在com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:98)在cn.itcast.util.JDBCUtils.getConnection(JDBCUtils.java:34)在cn.itcast.jdbc.DruidDemo.main(DruidDemo.java:10)目前使用的druid版本为1.0.9，mysql-connector-java版本为8.0.16。尝试升级druid版本到1.1.19时，可以正常获取连接
