APIExceptionHandler_handleBadRequest.java

    @ExceptionHandler(NotFoundException.class)
    public ResponseEntity<HttpClientErrorException> handleNotFound(NotFoundException ex, WebRequest req) {
        ProblemDetail p = ProblemDetail.forStatus(ex.getStatusCode());
        URI type = new DefaultUriBuilderFactory()
                .uriString("https://yoursite.acme.com/not-found/{error-code}")
                .build(Map.of("error-code", ex.getErrorCode()));
        p.setDetail(ex.getStatusText());
        p.setTitle("Object not found");
        p.setType(type);
        p.setProperty("hint", "hint-value");
        return ResponseEntity.of(p).build();
    }