Can you explain how the Spring MVC architecture works and what its main components are?

Spring MVC is a framework for building web applications in Java, based on the Model-View-Controller (MVC) pattern. Its main task is to divide the application logic into three parts:

• Model — contains business logic and data.
• View — responsible for displaying data to the user (e.g., JSP, Thymeleaf).
• Controller — handles incoming HTTP requests, interacts with the model, and selects the view for display.

Main components of Spring MVC:

1. DispatcherServlet — the central servlet that receives all requests and distributes them to controllers.
2. HandlerMapping — determines which controller should handle a specific request.
3. Controller — a class with methods annotated, for example, with @RequestMapping, that handle requests.
4. ViewResolver — selects a specific view template to display the result.
5. ModelAndView — an object that contains the model and the view name.

Example of a simple controller:

@Controller
public class HelloController {
    @RequestMapping("/hello")
    public String sayHello(Model model) {
        model.addAttribute("message", "Hello, Spring MVC!");
        return "helloView"; // view name
    }
}