Spring validation returns long error messages, not just the customized message - spring-boot

Question

Spring validation returns long error message instead of the customized once.
This is the section of code in the dto.
public class RequestDto implements Serializable {
#NotNull(message="{id.required}")
private Long id;
}
In controller added the #Valid for input.
#RequestMapping(value = ApiPath.PATH, method = RequestMethod.POST, produces = { "application/xml",
"application/json" })
public #ResponseBody ResultDecorator saveRequest(
#Valid #RequestBody RequestDto msaDisabScreenRequestDto) throws Exception {
}
API returns the following error.
<message>Validation failed for argument at index 0 in method: public om.gov.moh.msa.framework.resolver.ResultDecorator om.controller.MaController.saveRequest(om..dto.RequestDto) throws java.lang.Exception, with 1 error(s): [Field error in object 'requestDto' on field 'id': rejected value [null]; codes [NotNull.requestDto.id,NotNull.id,NotNull.java.lang.Long,NotNull]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [requestDto.id,id]; arguments []; default message [civilId]]; **default message [ID is required.]]** </message>
Here the custom message is present at the end. (default message [ID is required.)
Using Controller advice for global exception and I'm overriding handleMethodArgumentNotValid. How can I return only the custom message here?
#Order(Ordered.HIGHEST_PRECEDENCE)
#ControllerAdvice
public class RestExceptionHandler extends ResponseEntityExceptionHandler {
/**
* Spring validation related exception
*/
#Override
protected ResponseEntity<Object> handleMethodArgumentNotValid(
MethodArgumentNotValidException ex,
HttpHeaders headers,
HttpStatus status,
WebRequest request) {
ApiError apiError = new ApiError(HttpStatus.BAD_REQUEST);
apiError.setMessage(ex.getMessage());
return buildResponseEntity(apiError);
}
}

Answer 1

You can get default/custom message like result.getFieldError("yourFieldName").getDefaultMessage()
You can catch error messages either through controller method which should look like this
#RequestMapping(value = ApiPath.PATH, method = RequestMethod.POST, produces = { "application/xml", "application/json" })
public #ResponseBody ResultDecorator saveRequest(#Valid #RequestBody RequestDto msaDisabScreenRequestDto, BindingResult result) throws Exception {
if(result.hasErrors()){
String errorMessage = result.getFieldError("yourFieldName").getDefaultMessage();
}
}
Or through Global Exception handler
Updated
#Order(Ordered.HIGHEST_PRECEDENCE)
#ControllerAdvice
public class RestExceptionHandler extends ResponseEntityExceptionHandler {
/**
* Spring validation related exception
*/
#Override
protected ResponseEntity<Object> handleMethodArgumentNotValid(
MethodArgumentNotValidException ex,
HttpHeaders headers,
HttpStatus status,
WebRequest request) {
//New Code
BindingResult bindingResult = ex.getBindingResult();
String errorMessage = result.getFieldError("yourFieldName").getDefaultMessage();
//---------------
ApiError apiError = new ApiError(HttpStatus.BAD_REQUEST);
apiError.setMessage(errorMessage);
return buildResponseEntity(apiError);
}
}

Answer 2

Thanks Afridi,
Created a string buffer and added all the error messages into that.
/**
* Spring validation related exception
*/
#Override
protected ResponseEntity<Object> handleMethodArgumentNotValid(
MethodArgumentNotValidException ex,
HttpHeaders headers,
HttpStatus status,
WebRequest request) {
final StringBuffer errors = new StringBuffer();
ApiError apiError = new ApiError(HttpStatus.BAD_REQUEST);
for (final FieldError error : ex.getBindingResult().getFieldErrors()) {
errors.append("\n");
errors.append(error.getField() + ": " + error.getDefaultMessage());
}
apiError.setMessage(errors.toString());
return buildResponseEntity(apiError);
}

Answer 3

As Afridi said in #ControllerAdvice can do this also:
#ExceptionHandler(value = MethodArgumentNotValidException.class)
#SuppressWarnings("unchecked")
#ResponseBody
public Result methodArgumentNotValidExceptionHandler(HttpServletRequest req, HttpServletResponse response, MethodArgumentNotValidException e) throws IOException {
String message = e.getBindingResult().getAllErrors().get(0).getDefaultMessage();
// todo return to your custom result
}
There are two point :
Exception class is MethodArgumentNotValidException
The first Error getDefaultMessage() can get your custom message in Annotation

Answer 4

In WebFlux :
Handle WebExchangeBindException for customising the default error message of #Valid
#ControllerAdvice
public class ValidationHandler {
#ExceptionHandler(WebExchangeBindException.class)
public ResponseEntity<List<String>> handleException(WebExchangeBindException e) {
var errors = e.getBindingResult()
.getAllErrors()
.stream()
.map(DefaultMessageSourceResolvable::getDefaultMessage)
.collect(Collectors.toList());
return ResponseEntity.badRequest().body(errors);
}
}
Reference : https://www.vinsguru.com/spring-webflux-validation/