### Question:
UserApi { public void updateUser(String username, User body) throws RestClientException { Object postBody = body; if (username == null) { throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'username' when calling updateUser"); } if (body == null) { throw new HttpClientErrorException(HttpStatus.BAD_REQUEST, "Missing the required parameter 'body' when calling updateUser"); } final Map<String, Object> uriVariables = new HashMap<String, Object>(); uriVariables.put("username", username); String path = UriComponentsBuilder.fromPath("/user/{username}").buildAndExpand(uriVariables).toUriString(); final MultiValueMap<String, String> queryParams = new LinkedMultiValueMap<String, String>(); final HttpHeaders headerParams = new HttpHeaders(); final MultiValueMap<String, Object> formParams = new LinkedMultiValueMap<String, Object>(); final String[] accepts = { "application/xml", "application/json" }; final List<MediaType> accept = apiClient.selectHeaderAccept(accepts); final String[] contentTypes = { }; final MediaType contentType = apiClient.selectHeaderContentType(contentTypes); String[] authNames = new String[] { }; ParameterizedTypeReference<Void> returnType = new ParameterizedTypeReference<Void>() {}; apiClient.invokeAPI(path, HttpMethod.PUT, queryParams, postBody, headerParams, formParams, accept, contentType, authNames, returnType); } UserApi(); @Autowired  UserApi(ApiClient apiClient); ApiClient getApiClient(); void setApiClient(ApiClient apiClient); void createUser(User body); void createUsersWithArrayInput(List<User> body); void createUsersWithListInput(List<User> body); void deleteUser(String username); User getUserByName(String username); String loginUser(String username, String password); void logoutUser(); void updateUser(String username, User body);  }### Answer:
@Test public void updateUserTest() { String username = null; User body = null; api.updateUser(username, body); }