### Question:
AdminBasicInfoServiceImpl implements AdminBasicInfoService { @Override public Response modifyConfig(Config c, HttpHeaders headers) { HttpEntity requestEntity = new HttpEntity(c, headers); ResponseEntity<Response> re = restTemplate.exchange( configs, HttpMethod.PUT, requestEntity, Response.class); return re.getBody(); }  @Override Response getAllContacts(HttpHeaders headers); @Override Response deleteContact(String contactsId, HttpHeaders headers); @Override Response modifyContact(Contacts mci, HttpHeaders headers); @Override Response addContact(Contacts c, HttpHeaders headers); @Override Response getAllStations(HttpHeaders headers); @Override Response addStation(Station s, HttpHeaders headers); @Override Response deleteStation(Station s, HttpHeaders headers); @Override Response modifyStation(Station s, HttpHeaders headers); @Override Response getAllTrains(HttpHeaders headers); @Override Response addTrain(TrainType t, HttpHeaders headers); @Override Response deleteTrain(String id, HttpHeaders headers); @Override Response modifyTrain(TrainType t, HttpHeaders headers); @Override Response getAllConfigs(HttpHeaders headers); @Override Response addConfig(Config c, HttpHeaders headers); @Override Response deleteConfig(String name, HttpHeaders headers); @Override Response modifyConfig(Config c, HttpHeaders headers); @Override Response getAllPrices(HttpHeaders headers); @Override Response addPrice(PriceInfo pi, HttpHeaders headers); @Override Response deletePrice(PriceInfo pi, HttpHeaders headers); @Override Response modifyPrice(PriceInfo pi, HttpHeaders headers);  }### Answer:
@Test public void testModifyConfig() { Config c = new Config(); HttpEntity<Config> requestEntity = new HttpEntity<>(c, headers); Mockito.when(restTemplate.exchange( "http: HttpMethod.PUT, requestEntity, Response.class)).thenReturn(re); response = adminBasicInfoService.modifyConfig(c, headers); Assert.assertEquals(new Response<>(null, null, null), response); }