How does DispatcherServlet work if we have multiple XML Configuration file ?

Answer 1

The web.xml file controls which context file DispatcherServlet is using. If you configure web.xml to have a DispatcherServlet with name em, then by default it uses em-servlet.xml to load the web context.

Your question is a bit confusing as to what you would actually like to do - do you want all "versions" to be available in the same instance of the application?

If so, the method you describe sounds unorthodox for how to present multiple languages / globalizing your application. Traditionally you would just have a single instance of the application and all the controllers/instances, and then handle translating user-visible messages at the display level. Spring has excellent support for this.

If your goal is to have a single instance of the application serve requests for all these languages/locales, then it sounds like you could do away with a lot of this redundancy.

Answer 2

The web.xml file can configure multiple DispatcherServlet instances, each having its own configuration. Each DispatcherServlet instance configures a WebApplicationContext separate from other DispatcherServlet instances, so you can use the same bean names without affecting the other application context.

<!-- configured by WEB-INF/ap-servlet.xml -->
<servlet>
    <servlet-name>ap</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>

<!-- configured by WEB-INF/em-servlet.xml -->
<servlet>
    <servlet-name>em</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>

You must also configure web.xml to map requests to the appropriate DispatcherServlet. For example, each region could have a different URL path.

<servlet-mapping>
    <servlet-name>ap</servlet-name>
    <url-pattern>/ap/*</url-pattern>
</servlet-mapping>

<servlet-mapping>
    <servlet-name>em</servlet-name>
    <url-pattern>/em/*</url-pattern>
</servlet-mapping>