為什麼applicationContext.xml和spring-servlet.xml中都有注解過濾<context:component-scan base-package="myproject"> 和<context:component-scan base-package="myproject.

在剛學習SpringMVC架構整合時，你也許會産生疑問為什麼Spring.xml和SpringMVC.xml中都有注解過濾。

<context:component-scan base-package="myproject"> 和<context:component-scan base-package="myproject.controller" />

在這裡有一個比較有意思的問題，初學者也會産生困惑，那麼他究竟有何不同？我思考和查詢很久，話不多說，也實踐做起：

（1）隻在applicationContext.xml中配置如下

<context:component-scan base-package="myproject">

啟動不報錯，，但@Controller失效

（2）隻在spring-servlet.xml中配置上述配置

 Error creating bean with name 'org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping#0' defined in ServletContext resource [/WEB-INF/spring-mvc-......

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'commonController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private eis.service.ICollegeServer eis.controller.CommonController.collService; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [eis.service.ICollegeServer] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations:

{@org.springframework.beans.factory.annotation.Autowired(required=true

)}

（3）在applicationContext.xml和spring-servlet.xml中都配置過濾<context:component-scan base-package="myproject"> 和<context:component-scan base-package="myproject.controller" />，

不報錯，請求正常，

總結：由此可以分析<context:component-scan base-package="myproject">主要過濾@Controller，同時還查資料了解<context:component-scan base-package="myproject.controller" /> 配置項不但啟用了對類包進行掃描以實施注釋驅動 Bean 定義的功能，同時還啟用了注釋驅動自動注入的功能。