If you want full control over the response message in every controller write a ControllerAdvice
. For example, that example transform MethodArgumentNotValidException
into a custom json object:
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;
import java.util.ArrayList;
import java.util.List;
import static org.springframework.http.HttpStatus.BAD_REQUEST;
/**
* Kudos http://www.petrikainulainen.net/programming/spring-framework/spring-from-the-trenches-adding-validation-to-a-rest-api/
*
*/
@Order(Ordered.HIGHEST_PRECEDENCE)
@ControllerAdvice
public class MethodArgumentNotValidExceptionHandler {
@ResponseStatus(BAD_REQUEST)
@ResponseBody
@ExceptionHandler(MethodArgumentNotValidException.class)
public Error methodArgumentNotValidException(MethodArgumentNotValidException ex) {
BindingResult result = ex.getBindingResult();
List<org.springframework.validation.FieldError> fieldErrors = result.getFieldErrors();
return processFieldErrors(fieldErrors);
}
private Error processFieldErrors(List<org.springframework.validation.FieldError> fieldErrors) {
Error error = new Error(BAD_REQUEST.value(), "validation error");
for (org.springframework.validation.FieldError fieldError: fieldErrors) {
error.addFieldError(fieldError.getField(), fieldError.getDefaultMessage());
}
return error;
}
static class Error {
private final int status;
private final String message;
private List<FieldError> fieldErrors = new ArrayList<>();
Error(int status, String message) {
this.status = status;
this.message = message;
}
public int getStatus() {
return status;
}
public String getMessage() {
return message;
}
public void addFieldError(String path, String message) {
FieldError error = new FieldError(path, message);
fieldErrors.add(error);
}
public List<FieldError> getFieldErrors() {
return fieldErrors;
}
}
}