### Question:
CommandAuthorizationRepository { public CommandAuthorization find(String chargingStationId, String userIdentity, Class commandClass) { CommandAuthorizationId id = new CommandAuthorizationId(chargingStationId, userIdentity, commandClass); EntityManager em = getEntityManager(); try { return em.find(CommandAuthorization.class, id); } finally { em.close(); } }  CommandAuthorization find(String chargingStationId, String userIdentity, Class commandClass); CommandAuthorization createOrUpdate(String chargingStationId, String userIdentity, Class commandClass); void remove(String chargingStationId, String userIdentity, Class commandClass); void setEntityManagerFactory(EntityManagerFactory entityManagerFactory);  }### Answer:
@Test public void findAuthorizationEmptyRepository() { CommandAuthorization commandAuthorization = commandAuthorizationRepository.find(CHARGING_STATION_ID.getId(), USER_IDENTITY.getId(), COMMAND_CLASS); assertNull(commandAuthorization); }