This is probably a simple question, but I am having some difficulty understanding how Spring MVC handles the multiple hierarchies that are often present in an MVC application.
In my web.xml I have a context defined as My understanding is that this is the Root Context
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
/WEB-INF/spring/root-context.xml
</param-value>
</context-param>
I also have a context defined at the servlet level, which I understand should inherit beens from the root context above.
<servlet>
<servlet-name>appServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
In order to make my app work I have the following in root-context.xml
<context:component-scan base-package="com.demo.service" />
and the following in servlet-context.xml
<annotation-driven />
<context:component-scan base-package="com.demo.controller" />
My question is this, if I change component scan to the following in the root context only and remove the component scan from the servlet context, why does the app refuse to load?
<context:component-scan base-package="com.demo" />
Annotation-specified bean name 'adminController' for bean class [com.demo.controller.AdminController] conflicts with existing, non-compatible bean definition of same name