使用springmvc时报错 org.springframework.beans.NullValueInNestedPathException: Invalid property 'department' of bean class [com.atguigu.springmvc.crud.entities.Employee]:Could not instantiate property type [com.atguigu.springmvc.crud.entities.Department] t…
严重: Servlet.service() for servlet [SpringMVC] in context with path [/ssm] threw exception [Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException…