RxJava - Getting Started

Les applications sont de plus en plus interconnectées. Une architecture type WOA (Web Oriented Archiecture) et l’utilisation des micros-services nécessitent de faire de plus en plus d’appel à différents services web. Comment composer un résultat à partir de ces différents services, sans avoir à ce soucier de l’ordre dans lequel les serveurs vont répondre ?

RxJava offre une manière élégante de faire de l’asynchrone et de la composition au sein de son application. Nous vous exposerons les concepts de Rx (Reactive eXtension) avant de vous montrer une mise en application.

David Wursteisen - Brice Dutheil / Human Talks Paris / 9 septembre 2014

Video link of this presentation : https://parleys.com/play/5496fd23e4b0c9badd302bd7/chapter0/about

Transcript

1. RxJava
   Getting Started
   Brice Dutheil / David Wursteisen
   

   View Slide

2. Brice Dutheil
   @BriceDutheil
   Indep, Devoxx France,
   Hackergarten Paris
   Qui sommes nous ?
   David Wursteisen
   @dwursteisen
   

   View Slide

3. Il était une fois...
   

   View Slide

4. Il était une fois...
   

   View Slide

5. Systèmes distribués
   

   View Slide

6. Systèmes distribués
   

   View Slide

7. Systèmes distribués
   

   View Slide

8. Systèmes distribués
   

   View Slide

9. Systèmes distribués
   The Internet
   

   View Slide

10. Systèmes distribués
    

    View Slide

11. Systèmes distribués
    

    View Slide

12. RxJava
    

    View Slide

13. Obervable
    

    View Slide

14. Obervable
    

    View Slide

15. Obervable
    

    View Slide

16. Obervable
    

    View Slide

17. Observable
    Observable.from(1, 2, 3, 4)
    

    View Slide

18. Observable
    Observable.from(1, 2, 3, 4)
    Observable.from(asyncTask.getFuture())
    

    View Slide

19. Observable
    Observable.from(1, 2, 3, 4)
    Observable.from(asyncTask.getFuture())
    Observable.range(1, 4400)
    

    View Slide

20. Observable
    Observable.from(1, 2, 3, 4)
    Observable.from(asyncTask.getFuture())
    Observable.range(1, 4400)
    Observable.timer(0, 5, TimeUnit.SECONDS)
    

    View Slide

21. Observable
    Observable.from(1, 2, 3, 4)
    Observable.from(asyncTask.getFuture())
    Observable.range(1, 4400)
    Observable.timer(0, 5, TimeUnit.SECONDS)
    Observable.create(...)
    

    View Slide

22. Observable
    Observable.from(1, 2, 3, 4)
    Observable.from(asyncTask.getFuture())
    Observable.range(1, 4400)
    Observable.timer(0, 5, TimeUnit.SECONDS)
    Observable.create(...)
    Observable.from(anIterable)
    Observable.just(73)
    Observable.error(new Exception())
    Observable.empty()
    ...
    

    View Slide

23. Observable
    Observable
    Observable
    Observable
    

    View Slide

24. Subscriber
    Observable.range(1, 4400)
    

    View Slide

25. Subscriber
    Observable.range(1, 4400)
    .subscribe(
    onNext
    )
    

    View Slide

26. Subscriber
    Observable.range(1, 4400)
    .subscribe(
    System.out::println
    )
    

    View Slide

27. Subscriber
    Observable.range(1, 4400)
    .subscribe(
    System.out::println,
    onError
    )
    

    View Slide

28. Subscriber
    Observable.range(1, 4400)
    .subscribe(
    System.out::println,
    System.err::println
    )
    

    View Slide

29. Subscriber
    Observable.range(1, 4400)
    .subscribe(
    System.out::println,
    System.err::println,
    onCompleted
    )
    

    View Slide

30. Subscriber
    Observable.range(1, 4400)
    .subscribe(
    System.out::println,
    System.err::println,
    () -> System.out.println(“finished”)
    )
    

    View Slide

31. Diagrammes Marble
    

    View Slide

32. Diagrammes Marble
    

    View Slide

33. Diagrammes Marble
    

    View Slide

34. Diagrammes Marble
    

    View Slide

35. Diagrammes Marble
    

    View Slide

36. Diagrammes Marble
    

    View Slide

37. Diagrammes Marble
    

    View Slide

38. Diagrammes Marble
    

    View Slide

39. Opérateurs
    Observable.from(1, 2, 3, 4)
    

    View Slide

40. Opérateurs
    Observable.from(1, 2, 3, 4)
    .filter(predicate)
    

    View Slide

41. Opérateurs
    Observable.from(1, 2, 3, 4)
    .filter((i) -> (i % 2) == 0)
    

    View Slide

42. Opérateurs
    Observable.from(1, 2, 3, 4)
    .filter((i) -> (i % 2) == 0)
    .subscribe(System.out::println)
    

    View Slide

43. Opérateurs
    Observable.from(1, 2, 3, 4)
    .filter((i) -> (i % 2) == 0)
    .subscribe(System.out::println)
    

    View Slide

44. Opérateurs
    Observable.from(1, 2, 3, 4)
    .filter((i) -> (i % 2) == 0)
    .subscribe(System.out::println)
    2
    

    View Slide

45. Opérateurs
    Observable.from(1, 2, 3, 4)
    .filter((i) -> (i % 2) == 0)
    .subscribe(System.out::println)
    2
    4
    

    View Slide

46. Opérateurs
    Observable.from(1, 2, 3, 4)
    .take(2)
    .subscribe(System.out::println);
    

    View Slide

47. Opérateurs
    Observable.from(1, 2, 3, 4)
    .take(2)
    .subscribe(System.out::println);
    1
    2
    

    View Slide

48. Opérateurs
    Observable.from(1, 2, 3, 4)
    .map((i) -> i * 10)
    .subscribe(System.out::println);
    

    View Slide

49. Opérateurs
    Observable.from(1, 2, 3, 4)
    .map((i) -> i * 10)
    .subscribe(System.out::println);
    10
    20
    30
    40
    

    View Slide

50. Composition
    

    View Slide

51. Composition
    

    View Slide

52. Composition
    

    View Slide

53. Composition
    couleurs
    formes
    

    View Slide

54. Programmation synchrone
    observableReadingSynchronously(“strings.txt”)
    .take(10)
    .delay(1, SECONDS)
    .map(parse())
    .map(n -> “=> ” + n))
    .subscribe(to_the_view())
    

    View Slide

55. Programmation synchrone
    main
    

    View Slide

56. Programmation synchrone
    observableReadingSynchronously(“strings.txt”)
    .take(10)
    .delay(1, SECONDS)
    .map(parse())
    .map(n -> “=> ” + n))
    .subscribe(to_the_view())
    

    View Slide

57. Programmation asynchrone
    Computation
    IO
    UI
    main
    source
    

    View Slide

58. Programmation asynchrone
    Computation
    IO
    UI
    main
    source
    ...
    .subscribeOn(Schedulers.io())
    

    View Slide

59. Programmation asynchrone
    Computation
    IO
    UI
    main
    source
    .take(...)
    .subscribeOn(Schedulers.io())
    

    View Slide

60. Programmation asynchrone
    Computation
    IO
    UI
    main
    .delay(..., Schedulers.computation())
    

    View Slide

61. Programmation asynchrone
    Computation
    IO
    UI
    main
    .delay(..., Schedulers.computation())
    .map(...)
    

    View Slide

62. Programmation asynchrone
    Computation
    IO
    UI
    main
    .observeOn(Schedulers.from(...))
    .map(...)
    

    View Slide

63. Programmation asynchrone
    Computation
    IO
    UI
    main
    .observeOn(Schedulers.from(...))
    .map(...)
    .subscribe(...)
    

    View Slide

64. Programmation asynchrone
    observableReadingSynchronously(“strings.txt”)
    .subscribeOn(scheduler)
    .take(10)
    .delay(1, SECONDS, scheduler)
    .map(parse())
    .observeOn(scheduler)
    .map(n -> “=> ” + n))
    .subscribe(to_the_view())
    

    View Slide

65. Programmation asynchrone
    observableReadingSynchronously(“strings.txt”)
    .subscribeOn(Schedulers.io())
    .take(10)
    .delay(1, SECONDS, Schedulers.computation())
    .map(parse())
    .observeOn(Schedulers.from(uiExecutor()))
    .map(n -> “=> ” + n))
    .subscribe(to_the_view())
    

    View Slide

66. Aller plus loin
    Séquence
    finie & infinie
    Unsubscribe
    BackPressure
    Reactive Streams
    Hot & Cold
    observable
    

    View Slide

67. Aller plus loin
    Séquence
    finie & infinie
    Unsubscribe
    BackPressure
    Reactive Streams
    Hot & Cold
    observable
    

    View Slide

68. Aller plus loin
    Séquence
    finie & infinie
    Unsubscribe
    BackPressure
    Reactive Streams
    Hot & Cold
    observable
    

    View Slide

69. Aller plus loin
    Séquence
    finie & infinie
    Unsubscribe
    BackPressure
    Reactive Streams
    Hot & Cold
    observable
    

    View Slide

70. Aller plus loin
    Séquence
    finie & infinie
    Unsubscribe
    BackPressure
    Reactive Streams
    Hot & Cold
    observable
    

    View Slide

71. Aller plus loin
    Séquence
    finie & infinie
    Unsubscribe
    BackPressure
    Reactive Streams
    Hot & Cold
    observable
    

    View Slide

72. Questions ?
    

    View Slide