Spring MVC Error Handling Guide: Default WebErrorHandler & Custom Exceptions

Introduction

Robust error handling is essential for delivering reliable and secure Spring MVC applications. Out of the box, Spring provides a powerful WebErrorHandler that maps common exceptions to meaningful HTTP status codes and messages. This guide explores Spring’s default behavior, how to customize it, and best practices for building developer-friendly error responses.

Why Spring’s Default Error Handling Matters

Spring MVC’s built-in error handling simplifies debugging and response standardization:

• Automatically maps exceptions to HTTP status codes (e.g., 404, 400).
• Returns structured error payloads for frontend and API clients.
• Improves transparency with helpful error codes and message details.

Common Spring MVC Exception Mappings

💡 Note: Spring also supports ResponseStatusException for setting status codes directly in your code.

Customizing Error Responses

While the default mappings are helpful, you can override them to align with your app’s UX and logging strategy.

✅ Example: Custom Error Response

@ControllerAdvice
public class CustomExceptionHandler extends ResponseEntityExceptionHandler {

    @Override
    protected ResponseEntity<Object> handleHttpMessageNotReadable(
        HttpMessageNotReadableException ex,
        HttpHeaders headers,
        HttpStatus status,
        WebRequest request) {

        Map<String, Object> body = Map.of(
            "error", "Invalid request body",
            "code", "CUSTOM_400"
        );

        return ResponseEntity.badRequest().body(body);
    }
}

🔍 Other Customization Options

• Use @ExceptionHandler methods for domain-specific exceptions.
• Log errors centrally with SLF4J or Spring AOP.
• Mask internal details for production environments.

Best Practices for Spring Error Handling

✅ 1. Centralize Logic with @ControllerAdvice
Keep error handling consistent across controllers.

✅ 2. Use ResponseStatusException for Simplicity
No need to create custom exception classes for simple status mappings:

throw new ResponseStatusException(HttpStatus.NOT_FOUND, "User not found");

✅ 3. Hide Sensitive Information
Never expose stack traces or internal exception details in API responses.

✅ 4. Standardize Error Formats
Use consistent fields like error_code, message, and timestamp for easy client parsing.

FAQs

Q1: How can I disable or override Spring’s default WebErrorHandler?
Override relevant methods in ResponseEntityExceptionHandler or register a custom HandlerExceptionResolver.

Q2: How do I return custom error codes for my exceptions?
Use @ExceptionHandler and define your error payload structure.

Q3: Why am I getting a 500 error instead of 400?
Check if your exception is not mapped or lacks a proper @ResponseStatus annotation.

Conclusion

Spring MVC’s WebErrorHandler gives you a solid starting point for error handling. But for clean, secure, and well-documented APIs, customization is key. By combining Spring’s built-in features like @ControllerAdvice and ResponseStatusException with a few best practices, you can build resilient applications that handle errors gracefully.

Keywords: Spring MVC error handling, WebErrorHandler, ResponseStatusException, @ControllerAdvice, HTTP status Spring, customize Spring exceptions, Spring API error response

💡 Why This Guide Works

• Aligned with Spring Framework 5+ conventions
• Includes real-world code examples
• Practical advice for REST APIs and web apps

Now you’re equipped to master error handling in Spring MVC — and build cleaner, more reliable APIs! 🛠️

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