Springboot异常：Unsatisfied dependency expressed through field 'userDao'

报错信息：

Unsatisfied dependency expressed through field ‘userDao’; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type ‘com.rick.dao.UserDao’ available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

解决方法：

忘了扫描，对于包的扫描有两种方法：
一种是在mapper中直接加入@mapper，但是每个mapper都需要加注解
另一种是在application中加入扫描路径
@MapperScan(basePackages = "com.rick.dao")