Q1. What is Spring MVC?
Spring MVC is a web framework built on the Model-View-Controller design pattern. It provides a clean separation between domain model, web presentation, and request handling. It's part of the Spring Framework and offers features like declarative request mapping, form handling, validation, and integration with various view technologies (JSP, Thymeleaf, etc.).
Q2. What is DispatcherServlet?
DispatcherServlet is the front controller in Spring MVC. It intercepts all incoming HTTP requests and delegates them to appropriate handlers (controllers). It is configured in web.xml or through Java config. It uses HandlerMapping to determine which controller handles the request, and ViewResolver to resolve views.
Q3. What is a Controller in Spring MVC?
A controller is a class that handles HTTP requests. It is annotated with @Controller. Methods in the controller are mapped to specific URLs using @RequestMapping (or shortcut annotations like @GetMapping). Controllers return model and view information, or REST responses.
Q4. What is the role of @RequestMapping annotation?
@RequestMapping maps HTTP requests to handler methods. It can be applied at class level (base URL) and method level. It supports attributes like value (URL), method (HTTP method), params, headers, consumes, produces. Shortcuts: @GetMapping, @PostMapping, etc.
Q5. Explain the flow of a Spring MVC request.
1. Client sends request to DispatcherServlet. 2. DispatcherServlet consults HandlerMapping to find the appropriate controller. 3. Controller processes request, sets model data, and returns logical view name. 4. DispatcherServlet uses ViewResolver to map view name to actual view. 5. View renders the model and returns response.