Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.imut.service.IUserService] found for dependency [com.imut.service.IUserService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1398)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1051)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1018)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:643)

    ... 28 more
解决办法：

1、少了常用的注解标签：@Repository @Service ：这里的如果写（"value"），value还不能重复

2、没有加扫描context:component-scan：这里的dao的impl层，service的impl层还有controller层

<!-- 自动扫描(自动注入) -->

<context:component-scan base-package="包路径"/>    //在spring的配置文件中

3、超级愚蠢的错误！

这个setStudentDao（）必须在@Autowired下面！