我尝试重写handleMethodArgumentNotValid方法，但没有成功。
我得到的错误是："CustomResponseEntityExceptionHandler类型的方法handleMethodArgumentNotValid（方法参数无效异常，HttpHeaders，HttpStatus，WebRequest）必须重写或实现超类型，但我不知道为什么我还没有这样做。
我是这么做的：

@ControllerAdvice
@RestController
public class CustomResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {

@ExceptionHandler(Exception.class)
public final ResponseEntity<Object> handleAllExceptions(Exception ex, WebRequest request) {
    var exceptionResponse = new ExceptionResponse(new Date(), ex.getMessage(), request.getDescription(false));

    return new ResponseEntity<Object>(exceptionResponse, HttpStatus.INTERNAL_SERVER_ERROR);
}

@Override
protected ResponseEntity<Object> handleMethodArgumentNotValid(MethodArgumentNotValidException ex, HttpHeaders headers, HttpStatus status, WebRequest request) {
    return new ResponseEntity<Object>("test", HttpStatus.NOT_ACCEPTABLE);
}

@ExceptionHandler(UserNotFoundException.class)
public final ResponseEntity<Object> handleUserNotFoundExceptions(Exception ex, WebRequest request) {
    var exceptionResponse = new ExceptionResponse(new Date(), ex.getMessage(), request.getDescription(false));

    return new ResponseEntity<Object>(exceptionResponse, HttpStatus.NOT_FOUND);
}

}
我下面这个教程，如果它的任何帮助：https://www.baeldung.com/global-error-handler-in-a-spring-rest-api