private RewardNetworkImpl rewardNetwork;
@Before
public void setUp() {
// create stubs to facilitate fast in-memory testing with dummy data and no external dependencies
AccountMapper accountRepo = new StubAccountRepository();
RestaurantMapper restaurantRepo = new StubRestaurantRepository();
RewardRepository rewardRepo = new StubRewardRepository();
// setup the object being tested by handing what it needs to work
rewardNetwork = new RewardNetworkImpl(accountRepo, restaurantRepo, rewardRepo);