ViewResolver – Rendering Views

In Spring MVC, ViewResolver is the component responsible for rendering the final output that users see in their browser. Once the controller finishes processing a request, ViewResolver decides which view file should be used and how that view should be rendered.

In simple terms, the controller decides what data to show, while ViewResolver decides how that data is presented on the screen. This clear separation makes Spring MVC applications clean, flexible, and easy to maintain.

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What Is ViewResolver?

ViewResolver is a core Spring MVC component that maps a logical view name returned by a controller to an actual view technology, such as JSP, Thymeleaf, or FreeMarker.

When a controller returns a view name like:

"home"
"userProfile"

Spring does not know which physical file to render.

The ViewResolver resolves this logical name into a real file path, for example:

/WEB-INF/views/home.jsp

or

templates/userProfile.html

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Why ViewResolver Is Needed

Controllers should focus only on business logic, not on UI rendering details.

Without ViewResolver:

• Controllers would need to return full file paths
• Applications would become tightly coupled
• Changing the UI technology would require code changes

With ViewResolver:

• Controllers stay clean and reusable
• UI technologies can be changed easily
• Application becomes maintainable and scalable

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Where ViewResolver Fits in the Spring MVC Flow

In Spring MVC, every HTTP request follows a well-defined lifecycle. ViewResolver plays its role only when a view needs to be rendered.

Spring MVC Request Flow

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When ViewResolver Is Used

• If the controller returns a logical view name (for example, "home" or "userProfile"):
  • ViewResolver is invoked
  • It resolves the view name to a real template (JSP, Thymeleaf, FreeMarker)
  • The view is rendered and sent as HTML to the client

Example:

return"home";

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When ViewResolver Is Skipped

• If the controller returns:
  • JSON
  • XML
  • ResponseEntity
  • Or uses @RestController / @ResponseBody

In this case:

• ViewResolver is NOT involved
• HttpMessageConverters serialize the response data
• The response is written directly to the HTTP body

Example:

return ResponseEntity.ok(user);

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How ViewResolver Works

When a client sends a request, it flows through the DispatcherServlet and reaches the controller. After processing, the controller returns:

• A logical view name
• Along with model data

The DispatcherServlet then asks the ViewResolver to resolve the view name.

The ViewResolver:

1. Locates the correct view file
2. Merges model data into the view
3. Renders the final HTML
4. Sends the response back to the client

Simplified Flow

Client → DispatcherServlet → Controller → ViewResolver → View → Response

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Example – ViewResolver in Action

Controller Code

@Controller
publicclassHomeController {

@GetMapping("/home")
public StringhomePage(Model model) {
        model.addAttribute("message","Welcome to Spring MVC");
return"home";
    }
}

What Happens Internally

• Controller returns "home" as the logical view name
• ViewResolver resolves it to:

  • /WEB-INF/views/home.jsp

    or

  • templates/home.html

• Model data is injected into the view
• Final HTML is rendered and sent to the browser

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Common ViewResolver Implementations in Spring MVC

Spring MVC supports multiple view technologies, each with its own ViewResolver.

InternalResourceViewResolver

• Commonly used with JSP.
• It resolves logical view names to JSP files under a fixed directory.

Example:

home → /WEB-INF/views/home.jsp

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ThymeleafViewResolver

Used with Thymeleaf templates, especially popular in Spring Boot applications.

Example:

profile → templates/profile.html

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FreeMarkerViewResolver

• Used when FreeMarker is the chosen template engine.
• Often preferred for complex or dynamic UI rendering.

Example:

email → templates/email.ftl

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BeanNameViewResolver

• Resolves views based on bean names defined in the Spring context.
• Less commonly used, but useful in advanced customization scenarios.

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Why ViewResolver Is Important

ViewResolver provides several key benefits:

• Separates business logic from presentation logic
• Keeps controllers clean and focused
• Supports multiple view technologies
• Makes UI changes easier
• Improves maintainability and scalability

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ViewResolver vs REST APIs in Spring MVC

Aspect	ViewResolver (Spring MVC)	REST APIs (Spring MVC / Spring Boot)
Purpose	Used to render HTML pages that users can directly see in a web browser	Used to return raw data that is consumed by frontend apps, mobile apps, or other services
Used In	Traditional server-side web applications such as dashboards, admin panels, and websites	Modern applications like single-page apps, mobile apps, microservices, and integrations
Controller Type	Uses @Controller where methods return logical view names	Uses @RestController or @ResponseBody where methods return data directly
Return Type	Returns a logical view name such as "home" or "profile"	Returns Java objects like User, List<User>, or ResponseEntity
Output	Final response is a fully rendered HTML page	Final response is JSON or XML data
View Technology	Works with JSP, Thymeleaf, FreeMarker, or other template engines	Does not use any view technology
Rendering Style	Server-side rendering where HTML is generated on the backend	No server-side rendering; only data is sent to the client
Uses ViewResolver	Yes, ViewResolver converts logical view names into actual view files	No, ViewResolver is completely skipped
Uses HttpMessageConverter	Not used for rendering HTML views	Used to convert Java objects into JSON or XML
Client Type	Mainly web browsers where users directly interact with UI	Frontend frameworks, mobile applications, and other backend services
Example Endpoint	/home returns an HTML page rendered on the server	/users returns JSON data representing users

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Conclusion

ViewResolver is the rendering engine selector of Spring MVC. After the controller completes its work, ViewResolver takes over to locate the correct view, render it with model data, and send the final response to the client.

Together with DispatcherServlet, HandlerMapping, and HandlerAdapter, ViewResolver completes the Spring MVC request lifecycle, ensuring a clean, flexible, and professional architecture suitable for real-world applications.