Cause: java.lang.ClassNotFoundException: Cannot find class: ${driver}

Mybatis主配置文件读取不到jdbc.properties

错误提示：

### Cause: java.sql.SQLException: Error setting driver on UnpooledDataSource. Cause: java.lang.ClassNotFoundException: Cannot find class: ${driver}

主配置文件源码图片：

修改方法：

<configuration> 标签后添加 <properties resource="jdbc.properties"/>

即添加到上图箭头处