### Question:
UserService { public Set<String> listNamesByTeams(Set<Long> teamIds, Status status, Role role) throws ShepherException { return userBiz.listNames(teamIds, status, role); }  User get(long id); User get(String name); User create(String name); User createIfNotExist(String name); List<User> listByTeams(Set<Long> teams, Status status, Role role); Set<String> listNamesByTeams(Set<Long> teamIds, Status status, Role role);  }### Answer:
@Test public void testListNamesByTeams() throws Exception { Set<Long> teams = new HashSet<>(); teams.add(1L); teams.add(2L); Set<String> names = userService.listNamesByTeams(teams, Status.AGREE, Role.MEMBER); Assert.assertNotNull(names); Assert.assertEquals(3, names.size()); }