@Test
public void getUserName_Success(){

ring username = "testuser";
ring email = "testUser@t-mobile.com";
sponse responsemock = getMockResponse(HttpStatus.OK, true, username);
irectoryUser directoryUser = new DirectoryUser();
     directoryUser.setDisplayName("testUser");
     directoryUser.setGivenName("testUser");
     directoryUser.setUserEmail("testUser@t-mobile.com");
     directoryUser.setUserId("testuser01");
     directoryUser.setUserName("testuser");
     List<DirectoryUser> persons = new ArrayList<>();
     persons.add(directoryUser);
     DirectoryObjects users = new DirectoryObjects();
     DirectoryObjectsList usersList = new DirectoryObjectsList();
     usersList.setValues(persons.toArray(new DirectoryUser[persons.size()]));
     users.setData(usersList);
     ResponseEntity<DirectoryObjects> responseEntity1 = ResponseEntity.status(HttpStatus.OK).body(users);
     when(directoryService.searchByUPN(directoryUser.getUserEmail())).thenReturn(responseEntity1);
ring originalUserName = oidcUtil.getUserName(email);
sertEquals(originalUserName, responsemock.getResponse().toString());
}