khunzohn

class FetchMacsUseCase constructor(
    private val productRepository: ProductRepository
) {
    fun run(): Observable<MacsPartialState> {
        return productRepository.fetchMacs()
            .toObservable()
            .map { MacsPartialState.MacsResult(it) }
            .cast(MacsPartialState::class.java)
            .startWith(MacsPartialState.LoadingMacs)
            .onErrorReturn { error -> MacsPartialState.LoadMacsError(error) }

khunzohn

data class MovieResponse(
    val errorCode: Int?,
    val errorMessage: String?,
    val results: List<MovieData>
)

khunzohn

viewModelScope.launch {
    try {
        val movies = movieService.getUpcomingMovies()
    } catch (e: Exception) {
        //...
    }
}

khunzohn

interface MovieService {
    @GET("movie/now_playing")
    suspend fun getUpcomingMovies(@Query("api_key") apiKey: String): Response<MovieResponse>
}

khunzohn

interface MovieService {

    @GET("movie/now_playing")
    suspend fun getUpcomingMovies(@Query("api_key") apiKey: String): Response<MovieResponse>
}

khunzohn

public void getUser(String userId) {
  getView().showLoading(“fetching user…”);
  
  Subscription sub = userRepository.getUser(userId) 
    .subscribeOn(Schedulers.io())
    .observeOn(AndroidScheduler.mainThread())
    .subscribe(user -> {
        getView().stopLoading();
        getView().render(user);
    },e->{

khunzohn

public final class User {
    public final String id;
    public final String name;
    public final Throwable error; // the reason for failing to fetch will be stored here
    public final State state; //either of SUCCESS,PROGRESS,ERROR enum
    
    public User(Throwable error, State state, String id, String name) {
        this.error = error;
        this.state = state;
        this.id = id;

khunzohn

override fun onCreate(savedInstanceState : Bundle?) {
    setContentView(R.layout.activity_upload)

    val digit = 2
    val wordTwo: String = digit.mapToWord() // return "Two"
}

khunzohn

fun Int.mapToWord(): String {
  val word: String
  when (this) { // this refers to Int with its scope limited to the method level
    0 -> word = "Zero"
    1 -> word = "One"
    2 -> word = "Two"
    // 3,4,5,6,7,8,9
    else -> word = "Invalid Digit Range"
  }
  return word

khunzohn

public class Utils { 
   public static String mapDigitToWord(int digit) throws DigitRangeException {
    if(digit < 0 || digit > 9)
      throw new DigitRangeException();
    
    switch (digit) {
      case 0: return "Zero";
      case 1: return "One";
      // case 2,3,...9
      default: return "";