### Question:
SantanderOauth2Service implements Oauth2Service, PkceOauth2Extension { @Override public List<ValidationError> validateGetAuthorizationRequestUri(Map<String, String> headers, Parameters parameters) { List<ValidationError> validationErrors = new ArrayList<>(); if (parameters.getScaOAuthLink() == null) { validationErrors.add(ValidationError.required(Parameters.SCA_OAUTH_LINK)); } if (parameters.getPaymentId() == null && parameters.getConsentId() == null) { validationErrors.add(ValidationError.required(Parameters.CONSENT_ID + " or " + Parameters.PAYMENT_ID)); } return validationErrors; } SantanderOauth2Service(Oauth2Service oauth2Service); static SantanderOauth2Service create(Aspsp aspsp, HttpClient httpClient, Pkcs12KeyStore keyStore); @Override URI getAuthorizationRequestUri(Map<String, String> headers, Parameters parameters); @Override List<ValidationError> validateGetAuthorizationRequestUri(Map<String, String> headers, Parameters parameters); @Override TokenResponse getToken(Map<String, String> headers, Parameters parameters);  }### Answer:
@Test void validateGetAuthorizationRequestUri() { List<ValidationError> validationErrors = oauth2Service.validateGetAuthorizationRequestUri(Collections.emptyMap(), new Parameters()); assertThat(validationErrors).containsExactly(ValidationError.required(Parameters.SCA_OAUTH_LINK), ValidationError.required(Parameters.CONSENT_ID + " or " + Parameters.PAYMENT_ID)); }