private SignedAuthRequestUrlBuilder urlBuilder = new SignedAuthRequestUrlBuilder();
@Before
public void prepare() throws NoSuchAlgorithmException, InvalidKeySpecException {
RSAKey key = new RSAKey(new Base64URL(n), new Base64URL(e), new Base64URL(d), KeyUse.SIGNATURE, null, new Algorithm(alg), kid, null, null, null);
Map<String, JWK> keys = Maps.newHashMap();
keys.put("client", key);
signingAndValidationService = new DefaultJwtSigningAndValidationService(keys);
signingAndValidationService.setDefaultSignerKeyId("client");