How does Spring MVC integrate with servlets and ensure HTTP request processing?

Spring MVC integrates with servlets through the DispatcherServlet — a central servlet configured in web.xml or via Java configuration. When an HTTP request arrives, it is intercepted by the DispatcherServlet, which analyzes the URL and finds the corresponding controller (usually annotated with @Controller). Then, the controller method is invoked, which processes the request and returns a model and view name. After that, the DispatcherServlet delegates to the ViewResolver to render the response.

Example configuration of DispatcherServlet in web.xml:

<servlet>
    <servlet-name>dispatcher</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
    <servlet-name>dispatcher</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

Thus, Spring MVC uses the standard servlet mechanism to handle requests, with the DispatcherServlet acting as the front controller, providing routing and processing of HTTP requests within the application.