java 48 lines · 7 steps

Centralized error handling in Spring

A single advice class maps each exception type to a standardized RFC 7807 ProblemDetail response.

Explained by highlit

Spring Intermediate exception-handling problemdetail rest-api http-status centralization

1@RestControllerAdvice
2public class GlobalExceptionHandler {
3 
  private static final Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);
5 
  @ExceptionHandler(ResourceNotFoundException.class)
  public ResponseEntity<ProblemDetail> handleNotFound(ResourceNotFoundException ex) {
      ProblemDetail body = ProblemDetail.forStatusAndDetail(HttpStatus.NOT_FOUND, ex.getMessage());
      body.setTitle("Resource Not Found");
      body.setProperty("resourceId", ex.getResourceId());
      return ResponseEntity.status(HttpStatus.NOT_FOUND).body(body);
  }
13 
  @ExceptionHandler(DuplicateResourceException.class)
  public ResponseEntity<ProblemDetail> handleDuplicate(DuplicateResourceException ex) {
      ProblemDetail body = ProblemDetail.forStatusAndDetail(HttpStatus.CONFLICT, ex.getMessage());
      body.setTitle("Resource Already Exists");
      return ResponseEntity.status(HttpStatus.CONFLICT).body(body);
  }
20 
  @ExceptionHandler(MethodArgumentNotValidException.class)
  public ResponseEntity<ProblemDetail> handleValidation(MethodArgumentNotValidException ex) {
      Map<String, String> errors = new HashMap<>();
      for (FieldError error : ex.getBindingResult().getFieldErrors()) {
          errors.put(error.getField(), error.getDefaultMessage());
      }
      ProblemDetail body = ProblemDetail.forStatusAndDetail(HttpStatus.BAD_REQUEST, "Validation failed");
      body.setTitle("Invalid Request");
      body.setProperty("errors", errors);
      return ResponseEntity.badRequest().body(body);
  }
32 
  @ExceptionHandler(BusinessRuleException.class)
  public ResponseEntity<ProblemDetail> handleBusinessRule(BusinessRuleException ex) {
      ProblemDetail body = ProblemDetail.forStatusAndDetail(HttpStatus.UNPROCESSABLE_ENTITY, ex.getMessage());
      body.setTitle("Business Rule Violation");
      body.setProperty("code", ex.getCode());
      return ResponseEntity.unprocessableEntity().body(body);
  }
40 
  @ExceptionHandler(Exception.class)
  public ResponseEntity<ProblemDetail> handleUnexpected(Exception ex) {
      log.error("Unhandled exception", ex);
      ProblemDetail body = ProblemDetail.forStatusAndDetail(HttpStatus.INTERNAL_SERVER_ERROR, "An unexpected error occurred");
      body.setTitle("Internal Server Error");
      return ResponseEntity.internalServerError().body(body);
  }
48}

01 / 01

STEP 01

Walkthrough

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Three takeaways

1@RestControllerAdvice lets you handle exceptions in one place instead of scattering try/catch across controllers.
2ProblemDetail gives every error a consistent, machine-readable shape with status, title, and custom properties.
3A catch-all Exception handler should log the cause and hide internal details behind a generic 500 message.

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