### Question:
AdorsysIntegServiceProvider implements AccountInformationServiceProvider, PaymentInitiationServiceProvider, Oauth2ServiceProvider { @Override public Oauth2Service getOauth2Service(Aspsp aspsp, HttpClientFactory httpClientFactory, Pkcs12KeyStore keyStore) { HttpClient httpClient = httpClientFactory.getHttpClient(getAdapterId()); return new AdorsysIntegOauth2Service(aspsp, httpClient, new BaseOauth2Api<>(httpClient, AuthorisationServerMetaData.class)); }  @Override PaymentInitiationService getPaymentInitiationService(Aspsp aspsp,
                                                                HttpClientFactory httpClientFactory,
                                                                Pkcs12KeyStore keyStore,
                                                                LinksRewriter linksRewriter); @Override AccountInformationService getAccountInformationService(Aspsp aspsp,
                                                                  HttpClientFactory httpClientFactory,
                                                                  Pkcs12KeyStore keyStore,
                                                                  LinksRewriter linksRewriter); @Override Oauth2Service getOauth2Service(Aspsp aspsp, HttpClientFactory httpClientFactory, Pkcs12KeyStore keyStore); @Override String getAdapterId();  }### Answer:
@Test void getOauth2Service() { Oauth2Service actualService = provider.getOauth2Service(null, httpClientFactory, null); assertThat(actualService) .isNotNull() .isInstanceOf(AdorsysIntegOauth2Service.class); }