小编Sam*_* T.的帖子

public class UserRepository {
private final Webservice webservice;
private final UserDao userDao;
private final Executor executor;

@Inject
public UserRepository(Webservice webservice, UserDao userDao, Executor executor) {
    this.webservice = webservice;
    this.userDao = userDao;
    this.executor = executor;
}

public LiveData<User> getUser(String userId) {
    refreshUser(userId);
    // Returns a LiveData object directly from the database.
    return userDao.load(userId);
}

private void refreshUser(final String userId) {
    // Runs in a background thread.
    executor.execute(() -> {
        // Check if user data was fetched recently.
        boolean userExists = userDao.hasUser(FRESH_TIMEOUT); …