RxJava, RxJava 2, Reactor : Etat de l’art des Reactive Streams en Java

2017 sera l’année des Reactive Streams en Java : RxJava est largement utilisé sur Android ou côté backend à travers Hystrix. RxJava 2 vient tout juste de sortir et va pouvoir profiter du chemin déjà tracé par sa précédente version. Pivotal pousse Reactor qui sera disponible dans le framework Spring version 5.

Qu’apportes ces différentes implémentations, en terme d’API ou de performances ? En quoi sont-elles différentes ? Faut-il migrer sur RxJava 2 tout de suite ? Reactor va-t’il remplacer RxJava et se limite t'il au framework Spring ?

Cette conférence fera un bref historique des ces bibliothèques avant de faire une comparaison des APIs, performances et cas d’utilisation de ces Reactive Streams.

Devoxx France ( Paris ) - 6 Avril 2017

Transcript

1. RxJava, RxJava 2, Reactor
   État de l’art des Reactive Streams sur la JVM
   

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2. David
   Wursteisen
   

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4. Écrire du code asynchrone : 

   ça craint
   

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5. Future
   ExecutorService ex = Executors.newCachedThreadPool();

   Future future = ex.submit(() -> longProcessing());

   String result = future.get();
   Appel bloquant
   

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6. Future
   Future> future1 = /* ... */

   Future> future2 = /* ... */

   Future> future3 = /* ... */

   Future> future4 = /* ... */

   Future> future5 = /* ... */
   Orchestration
   optimale ?
   

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7. Callback
   RemoteService service = buildRemoteService();

   service.getUser(id -> {

   service.getData(id, data -> {

   service.getSomething(data, whut -> {
   service.neverEndingCallBack(whut, () -> {
   });
   });

   });

   });
   Callback Hell
   

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8. Relationship Status:

   it’s complicated
   

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9. Le problème
   du code synchrone
   

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10. Synchrone
    Attente de la réponse
    Appelant
    Appelé
    

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11. Impacte le temps
    de réponse
    Serveur lent
    

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12. Il y a toujours
    un truc qui ne
    marche pas
    ça m’énerve !
    

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14. Ça ne
    marche pas !
    ça a planté ?
    dans le
    doute, reboot
    

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15. Asynchrone
    Appelant
    Appelé
    Traitement continu
    

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16. L’asynchrone permet de profiter
    du temps d’attente
    

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17. Impact minimum
    sur le temps de
    réponse
    

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19. Écrire du code asynchrone
    facilement ?
    

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20. Émergence 

    de différentes approches
    

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21. 2
    Reactive Streams
    

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22. Reactive Streams
    API Reactive Streams
    RxJava 2 Reactor
    Interface
    Implémentation
    

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23. L’API Reactive Streams est 

    un pont 

    entre les implémentations
    

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24. Contrat Reactive Streams
    onSubscribe onNext onError
    onComplete
    

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25. RxJava n’est
    pas compatible 

    avec Reactive Streams
    (il faut alors utiliser un adapteur : RxJavaReactiveStreams)
    https://github.com/ReactiveX/RxJavaReactiveStreams
    

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26. onNext * ( onError | onComplete )
    

    onNext * ( onError | onCompleted )
    RxJava
    Reactive Streams
    

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27. onNext * ( onError | onComplete )
    

    onNext * ( onError | onCompleted )
    RxJava
    Reactive Streams
    Nom différent
    

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28. Reactor
    peut utiliser
    RxJava 2
    et réciproquement
    

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29. Approche
    commune
    

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30. API pour manipuler 

    des événements de manière
    synchrone ou asynchrone
    à travers un flux d’événements
    

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32. Map ( ⃝ →
    ⬛)
    

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35. remoteApi.people(1).flatMap(luke -> {
    

    Observable vehicles = Observable.from(luke.getVehiclesIds())

    .flatMap(remoteApi::vehicle)

    .map(vehicle -> luke.getName() + " can drive " + vehicle.getName());

    

    Observable starships = Observable.from(luke.getStarshipsIds())

    .flatMap(remoteApi::starship)

    .map(starship -> luke.getName() + " can fly with " + starship.getName());

    

    return Observable.merge(vehicles, starships);
    

    }).subscribe(System.out::println);
    

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36. remoteApi.people(1).flatMap(luke -> {
    

    Observable vehicles = Observable.from(luke.getVehiclesIds())

    .flatMap(remoteApi::vehicle)

    .map(vehicle -> luke.getName() + " can drive " + vehicle.getName());

    

    Observable starships = Observable.from(luke.getStarshipsIds())

    .flatMap(remoteApi::starship)

    .map(starship -> luke.getName() + " can fly with " + starship.getName());

    

    return Observable.merge(vehicles, starships);
    

    }).subscribe(System.out::println);
    

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37. remoteApi.people(1).flatMap(luke -> {
    

    Observable vehicles = Observable.from(luke.getVehiclesIds())

    .flatMap(remoteApi::vehicle)

    .map(vehicle -> luke.getName() + " can drive " + vehicle.getName());

    

    Observable starships = Observable.from(luke.getStarshipsIds())

    .flatMap(remoteApi::starship)

    .map(starship -> luke.getName() + " can fly with " + starship.getName());

    

    return Observable.merge(vehicles, starships);
    

    }).subscribe(System.out::println);
    Push du résultat
    

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38. remoteApi.people(1).flatMap(luke -> {
    

    Observable vehicles = Observable.from(luke.getVehiclesIds())

    .flatMap(remoteApi::vehicle)

    .map(vehicle -> luke.getName() + " can drive " + vehicle.getName());

    

    Observable starships = Observable.from(luke.getStarshipsIds())

    .flatMap(remoteApi::starship)

    .map(starship -> luke.getName() + " can fly with " + starship.getName());

    

    return Observable.merge(vehicles, starships);
    

    }).subscribe(System.out::println);
    Récupération des
    véhicules de Luke
    Récupération des
    vaisseaux de Luke
    

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39. remoteApi.people(1).flatMap(luke -> {
    

    Observable vehicles = Observable.from(luke.getVehiclesIds())

    .flatMap(remoteApi::vehicle)

    .map(vehicle -> luke.getName() + " can drive " + vehicle.getName());

    

    Observable starships = Observable.from(luke.getStarshipsIds())

    .flatMap(remoteApi::starship)

    .map(starship -> luke.getName() + " can fly with " + starship.getName());

    

    return Observable.merge(vehicles, starships);
    

    }).subscribe(System.out::println);
    Flux 

    d’événements
    Flux 

    d’événements
    

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40. remoteApi.people(1).flatMap(luke -> {
    

    Observable vehicles = Observable.from(luke.getVehiclesIds())

    .flatMap(remoteApi::vehicle)

    .map(vehicle -> luke.getName() + " can drive " + vehicle.getName());

    

    Observable starships = Observable.from(luke.getStarshipsIds())

    .flatMap(remoteApi::starship)

    .map(starship -> luke.getName() + " can fly with " + starship.getName());

    

    return Observable.merge(vehicles, starships);
    

    }).subscribe(System.out::println);
    Fusion des 2 flux
    

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41. remoteApi.people(1).flatMap(luke -> {
    

    Observable vehicles = Observable.from(luke.getVehiclesIds())

    .flatMap(remoteApi::vehicle)

    .map(vehicle -> luke.getName() + " can drive " + vehicle.getName());

    

    Observable starships = Observable.from(luke.getStarshipsIds())

    .flatMap(remoteApi::starship)

    .map(starship -> luke.getName() + " can fly with " + starship.getName());

    

    return Observable.merge(vehicles, starships);
    

    }).subscribe(System.out::println);
    Déclenche l’exécution du
    code
    

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42. remoteApi.people(1).flatMap(luke -> {
    

    Observable vehicles = Observable.from(luke.getVehiclesIds())

    .flatMap(remoteApi::vehicle)

    .map(vehicle -> luke.getName() + " can drive " + vehicle.getName());

    

    Observable starships = Observable.from(luke.getStarshipsIds())

    .flatMap(remoteApi::starship)

    .map(starship -> luke.getName() + " can fly with " + starship.getName());

    

    return Observable.merge(vehicles, starships);
    

    }).subscribe(System.out::println);
    Flux 

    d’événements
    

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44. Button btn = new Button();

    btn.setText("Click Me");

    

    JavaFx.fromClick(btn) 

    .observeOn(Schedulers.io()) 

    .switchMap(evt -> remoteApi.getData())

    .observeOn(javaFx()) 

    .doOnNext(value -> btn.setText("Data: " + value))

    .subscribe();
    

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45. Button btn = new Button();

    btn.setText("Click Me");

    

    JavaFx.fromClick(btn) // Observable

    .observeOn(Schedulers.io())

    .switchMap(evt -> remoteApi.getData())

    .observeOn(javaFx()) 

    .doOnNext(value -> btn.setText("Data: " + value))

    .subscribe();
    Écoute des clicks
    

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46. Button btn = new Button();

    btn.setText("Click Me");

    

    JavaFx.fromClick(btn) // Observable

    .observeOn(Schedulers.io())

    .switchMap(evt -> remoteApi.getData())

    .observeOn(javaFx()) 

    .doOnNext(value -> btn.setText("Data: " + value))

    .subscribe();
    Changement du
    contexte d’exécution
    

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47. Button btn = new Button();

    btn.setText("Click Me");

    

    JavaFx.fromClick(btn) // Observable

    .observeOn(Schedulers.io())

    .switchMap(evt -> remoteApi.getData()) // Observable

    .observeOn(javaFx()) 

    .doOnNext(value -> btn.setText("Data: " + value))

    .subscribe();
    Appel asynchrone
    d’un web service
    

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48. Button btn = new Button();

    btn.setText("Click Me");

    

    JavaFx.fromClick(btn) // Observable

    .observeOn(Schedulers.io())

    .switchMap(evt -> remoteApi.getData()) // Observable

    .observeOn(javaFx()) 

    .doOnNext(value -> btn.setText("Data: " + value))

    .subscribe();
    Changement du
    contexte d’exécution
    

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49. Button btn = new Button();

    btn.setText("Click Me");

    

    JavaFx.fromClick(btn) // Observable

    .observeOn(Schedulers.io())

    .switchMap(evt -> remoteApi.getData()) // Observable

    .observeOn(javaFx()) 

    .doOnNext(value -> btn.setText("Data: " + value))

    .subscribe();
    Changement au niveau
    de l’UI
    

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50. Button btn = new Button();

    btn.setText("Click Me");

    

    JavaFx.fromClick(btn) // Observable

    .observeOn(Schedulers.io())

    .switchMap(evt -> remoteApi.getData()) // Observable

    .observeOn(javaFx()) 

    .doOnNext(value -> btn.setText("Data: " + value))

    .subscribe();
    Flux 

    d’événements
    

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51. Button btn = new Button();

    btn.setText("Click Me");

    

    ExecutorService io = Executors.newSingleThreadExecutor();

    btn.setOnAction(evt -> {

    io.submit(() -> {

    remoteApi.getData(data -> {

    Platform.runLater(() -> {

    btn.setText(data);

    });

    });

    });

    });
    Sac de noeud
    Structure pyramidale
    

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52. Grâce à RxJava
    et Reactor
    …
    

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53. Écrire du code asynchrone : 

    ça craint
    

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54. Il était une fois…
    

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55. Création des 

    Reactive Extensions
    Création de RxJava
    Participation active
    Reprise de 

    RxJava & RxJava 2
    Création de Reactor
    Participation à Reactor
    

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56. RxJava 

    est une technologie 

    éprouvée
    

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57. Reactor

    profite de l’expérience de 

    RxJava
    (et vice versa)
    

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58. Types d’objet
    

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59. Observable
    

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65. Single
    

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67. Completable
    

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69. RxJava
    Contrat Backpressure
    Observable [N] Oui
    Single [1] Non
    Completable [0] Non
    Ajouté après coup
    Appel Web
    service
    Processus
    d’arrière plan
    

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70. Écouter une websocket, pour
    c h a q u e c o m m a n d e r e ç u e ,
    composer une réponse à partir de
    3 webservices différents, puis
    exécuter 2 jobs séquentiellement ?
    

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71. Écouter une websocket, pour
    c h a q u e c o m m a n d e r e ç u e ,
    composer une réponse à partir de
    3 webservices différents, puis
    exécuter 2 jobs séquentiellement ?
    

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72. Écouter une websocket, pour
    c h a q u e c o m m a n d e r e ç u e ,
    composer une réponse à partir de
    3 webservices différents, puis
    exécuter 2 jobs séquentiellement ?
    

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73. Écouter une websocket, pour
    c h a q u e c o m m a n d e r e ç u e ,
    composer une réponse à partir de
    3 webservices différents, puis
    exécuter 2 jobs séquentiellement ?
    

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74. websocket("/topics/cmd")

    .observeOn(Schedulers.io())

    .switchMap(cmd ->

    Single.zip(

    api.getActions(),

    api.getScore(),

    api.getUserData(),

    this::composeResult).toObservable())

    .observeOn(Schedulers.computation())

    .concatMap(result -> updateDb(result).andThen(getLastResults()))

    .subscribe(last -> System.out.println("last results -> " + last));
    

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75. websocket("/topics/cmd")

    .observeOn(Schedulers.io())

    .switchMap(cmd ->

    Single.zip(

    api.getActions(),

    api.getScore(),

    api.getUserData(),

    this::composeResult).toObservable())

    .observeOn(Schedulers.computation())

    .concatMap(result -> updateDb(result).andThen(getLastResults()))

    .subscribe(last -> System.out.println("last results -> " + last));
    Écoute de la websocket
    Observable
    

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76. websocket("/topics/cmd")

    .observeOn(Schedulers.io())

    .switchMap(cmd ->

    Single.zip(

    api.getActions(),

    api.getScore(),

    api.getUserData(),

    this::composeResult).toObservable())

    .observeOn(Schedulers.computation())

    .concatMap(result -> updateDb(result).andThen(getLastResults()))

    .subscribe(last -> System.out.println("last results -> " + last));
    Composition d’une réponse à
    partir de 3 webservices
    Single
    

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77. websocket("/topics/cmd")

    .observeOn(Schedulers.io())

    .switchMap(cmd ->

    Single.zip(

    api.getActions(),

    api.getScore(),

    api.getUserData(),

    this::composeResult).toObservable())

    .observeOn(Schedulers.computation())

    .concatMap(result -> updateDb(result).andThen(getLastResults()))

    .subscribe(last -> System.out.println("last results -> " + last));
    Completable
    Exécuter 2 jobs
    

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78. websocket("/topics/cmd")

    .observeOn(Schedulers.io())

    .switchMap(cmd ->

    Single.zip(

    api.getActions(),

    api.getScore(),

    api.getUserData(),

    this::composeResult).toObservable())

    .observeOn(Schedulers.computation())

    .concatMap(result -> updateDb(result).andThen(getLastResults()))

    .subscribe(last -> System.out.println("last results -> " + last));
    Écoute de la websocket
    Observable Composition d’une réponse à
    partir de 3 webservices
    Single
    Completable
    Exécuter 2 jobs
    

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79. RxJava 2
    Contrat Backpressure
    Observable [N] Non
    Single [1] Non
    Completable [0] Non
    Maybe [0|1] Non Nouveau !
    Concept
    « similaire » à
    Optional
    

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80. Maybe
    

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82. Backpressure
    avec RxJava 2
    

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83. Consommateur
    

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84. Consommateur
    ça déborde !
    

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85. backpressure
    

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86. MissingBackpressureException ?
    

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87. acceptedIntent

    .filter(intent -> !intent.getBooleanExtra("UpdatePhoneMode", false))

    .concatMap(intent -> approximatedEngine.detectCurrentPlace())

    .doOnNext(score -> Log.info(TAG, "Scan completed with result " + score))

    .concatMap(this::detectSleepMode)

    .concatMap((score) -> isNewPlace(score.getScore().getPlace()).map(p -> score))

    .doOnNext((p) -> Log.info(TAG, "Current place found is : " + p))

    .subscribe()
    

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88. acceptedIntent

    .filter(intent -> !intent.getBooleanExtra("UpdatePhoneMode", false))
    .onBackpressureDrop()

    .concatMap(intent -> approximatedEngine.detectCurrentPlace())

    .doOnNext(score -> Log.info(TAG, "Scan completed with result " + score))

    .onBackpressureDrop()
    .concatMap(this::detectSleepMode)

    .onBackpressureDrop()

    .concatMap((score) -> isNewPlace(score.getScore().getPlace()).map(p -> score))

    .doOnNext((p) -> Log.info(TAG, "Current place found is : " + p))

    .subscribe()
    Ajouté dans un
    moment de
    panique
    

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89. RxJava 2
    Contrat Backpressure
    Observable [N] Non
    Single [1] Non
    Completable [0] Non
    Maybe [0|1] Non Nouveau !
    Concept
    « similaire » à
    Optional
    

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90. RxJava 2
    Contrat Backpressure
    Observable [N] Non
    Single [1] Non
    Completable [0] Non
    Maybe [0|1] Non
    Flowable [N] Oui
    Nouveau !
    Observable avec 

    back pressure
    Concept
    « similaire » à
    Optional
    

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91. Observable
    → moins de 1000 éléments
    → Gestion d’élément d’interface graphique
    → Remplacement de Stream Java
    Flowable
    → plus de 10 000 éléments
    → contrôle de l’émission de données
    → Flux réseau avec contrôle de débit
    

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92. Que propose
    Reactor ?
    

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93. Flux
    Mono
    Maximum 1 élément
    

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94. Reactor
    Contrat Backpressure
    Flux [N] Oui
    Mono [0|1] Oui
    Identique à
    Flowable
    Flux avec 

    au maximum 

    1 élément
    

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95. Types d’objets et

    Reactive Streams
    

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96. Publisher
    Flux Flowable
    Reactive Streams
    

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97. Flux.range(1, 10)

    .flatMap(i -> Flux.just(1))

    .subscribe();
    

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98. Flux.range(1, 10)

    .flatMap(i -> Flux.just(1))

    .subscribe();
    Publisher
    

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99. Flux.range(1, 10)

    .flatMap(i -> Flowable.just(1))

    .subscribe();
    Publisher
    RxJava 2
    

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100. Flowable.defer(() -> Flux.range(1, 10))

     .subscribe(System.out::println);
     RxJava 2 Reactor
     

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101. Flux.defer(() -> Flowable.range(1, 10))

     .subscribe(System.out::println);
     RxJava 2
     Reactor
     

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102. Encore plus de possibilités
     avec reactor-addons
     https://github.com/reactor/reactor-addons
     

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103. Observable.range(1, 10)

     .to(obs -> RxJava2Adapter.observableToFlux(obs, BackpressureStrategy.BUFFER))

     .checkpoint()

     .subscribe();
     Maybe.empty()

     .to(maybe -> RxJava2Adapter.maybeToMono(maybe))

     .checkpoint()

     .subscribe();
     Single.just(1)

     .to(single -> RxJava2Adapter.singleToMono(single))

     .checkpoint()

     .subscribe();
     Observable → Flux
     Single → Mono
     Maybe → Mono
     

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104. RxJava2Adapter.monoToFlowable(Mono.just(1))

     .timestamp()

     .subscribe();

     

     RxJava2Adapter.fluxToFlowable(Flux.range(1, 10))

     .timestamp()

     .subscribe();
     Mono → Flowable
     Flux → Flowable
     

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105. P o u v o i r u t i l i s e r u n e
     biblio t hèq ue utilisant
     RxJava 2 dans son projet
     Reactor
     (et vice versa)
     

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106. Opérateurs
     

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107. Catalogue
     conséquent et homogène
     

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108. all amb ambArray ambWith any as awaitOnSubscribe blockFirst blockFirstMillis blockLast blockLastMillis
     blockingFirst blockingForEach blockingIterable blockingLast blockingLatest blockingMostRecent blockingNext
     blockingSingle blockingSubscribe buffer bufferMillis bufferSize bufferTimeout bufferTimeoutMillis bufferUntil
     bufferWhile cache cacheWithInitialCapacity cancelOn cast checkpoint collect collectInto collectList collectMap
     collectMultimap collectSortedList combineLatest combineLatestDelayError compose concat concatArray
     concatArrayDelayError concatArrayEager concatDelayError concatEager concatMap concatMapDelayError
     concatMapEager concatMapEagerDelayError concatMapIterable concatWith contains count create debounce
     defaultIfEmpty defer delay delayElements delayElementsMillis delayMillis delaySubscription delaySubscriptionMillis
     dematerialize distinct distinctUntilChanged doAfterNext doAfterTerminate doFinally doOnCancel doOnComplete
     doOnEach doOnError doOnLifecycle doOnNext doOnRequest doOnSubscribe doOnTerminate elapsed elementAt
     elementAtOrError empty equals error filter first firstElement firstEmitting firstEmittingWith firstOrError flatMap
     flatMapCompletable flatMapIterable flatMapMaybe flatMapSequential flatMapSingle forEach forEachWhile from
     fromArray fromCallable fromFuture fromIterable fromPublisher fromStream generate getClass getPrefetch groupBy
     groupJoin handle hasElement hasElements hashCode hide ignoreElements interval intervalMillis intervalRange
     isEmpty join just last lastElement lastOrError lift limitRate log map mapError materialize merge mergeArray
     mergeArrayDelayError mergeDelayError mergeSequential mergeWith never next notify notifyAll observeOn ofType
     onBackpressureBuffer onBackpressureDrop onBackpressureError onBackpressureLatest onErrorResumeNext
     onErrorResumeWith onErrorReturn onErrorReturnItem onExceptionResumeNext onTerminateDetach parallel publish
     publishNext publishOn range rangeLong rebatchRequests reduce reduceWith repeat repeatUntil repeatWhen
     replay replayMillis retry retryUntil retryWhen safeSubscribe sample sampleFirst sampleFirstMillis sampleMillis
     sampleTimeout scan scanWith sequenceEqual serialize share single singleElement singleOrEmpty singleOrError
     skip skipLast skipMillis skipUntil skipUntilOther skipWhile sort sorted startWith startWithArray strict subscribe
     subscribeOn subscribeWith switchIfEmpty switchMap switchMapDelayError switchOnError switchOnNext
     switchOnNextDelayError take takeLast takeMillis takeUntil takeUntilOther takeWhile test then thenEmpty thenMany
     throttleFirst throttleLast throttleWithTimeout timeInterval timeout timeoutMillis timer timestamp to toFuture toIterable
     toList toMap toMultimap toObservable toSortedList toStream toString transform unsafeCreate unsubscribeOn using
     wait window windowMillis windowTimeout windowTimeoutMillis windowUntil windowWhile withLatestFrom zip
     zipArray zipIterable zipWith zipWithIterable
     

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109. RxJava RxJava 2 Reactor
     flatMap flatMap flatMap
     Émission d’aucune,
     une ou plusieurs
     valeurs
     amb amb firstEmitting
     Émission des valeurs
     du flux répondant en
     premier
     … … … …
     debounce debounce N/A
     Ignore les
     événements pendant
     un laps de temps
     

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110. RxJava RxJava 2 Reactor
     flatMap flatMap flatMap
     Émission d’aucune,
     une ou plusieurs
     valeurs
     amb amb firstEmitting
     Émission des valeurs
     du flux répondant en
     premier
     … … … …
     debounce debounce N/A
     Ignore les
     événements pendant
     un laps de temps
     Renommage
     

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111. L’ensemble des opérateurs
     couvre
     de nombreuses situations
     

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112. Nota bene
     

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113. https://github.com/ReactiveX/RxJava/wiki/Implementing-custom-operators-(draft)
     writing operators is hard
     when one writes an operator, the Observable
     protocol, unsubscription, backpressure and
     concurrency have to be taken into account and
     adhered to the letter
     

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114. Écrire un opérateur avec RxJava 2 est
     plus complexe
     qu’avec RxJava
     

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115. Rendre son application
     Reactive
     

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116. -Jake Wharton
     « Unless you can model your entire system
     synchronously, a single asynchronous source
     breaks imperative programming »
     

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117. -Jake Wharton
     « Unless you can model your entire system
     synchronously, a single asynchronous source
     breaks imperative programming »
     

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118. Reactive
     Reactive
     API Synchrone
     Callback
     Reactive
     Reactive
     

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119. Utilisation de
     Factory
     

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120. RxJava

     RxJava 2
     Reactor
     Flowable.just Flux.just
     Émission d’une valeur
     existante
     Flowable.defer Flux.defer
     Émission tardive d’un
     Observable
     Flowable.fromCallable Mono.fromCallable
     Émission à partir d’un appel
     de fonction
     Flowable.create Flux.create
     Contrôle manuel de l’émission
     des événements
     Flowable.using Flux.using Gestion d’une ressource
     Flowable.fromPublisher Flux.from
     Utilisation d’un Publisher
     (Reactive Streams)
     Flowable.generate Flux.generate
     Utilisation d’un générateur de
     valeurs
     

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121. RxJava

     RxJava 2
     Reactor
     Flowable.just Flux.just
     Émission d’une valeur
     existante
     Flowable.defer Flux.defer
     Émission tardive d’un
     Observable
     Flowable.fromCallable Mono.fromCallable
     Émission à partir d’un appel
     de fonction
     Flowable.create Flux.create
     Contrôle manuel de l’émission
     des événements
     Flowable.using Flux.using Gestion d’une ressource
     Flowable.fromPublisher Flux.from
     Utilisation d’un Publisher
     (Reactive Streams)
     Flowable.generate Flux.generate
     Utilisation d’un générateur de
     valeurs
     

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122. RxJava

     RxJava 2
     Reactor
     Flowable.just Flux.just
     Émission d’une valeur
     existante
     Flowable.defer Flux.defer
     Émission tardive d’un
     Observable
     Flowable.fromCallable Mono.fromCallable
     Émission à partir d’un appel
     de fonction
     Flowable.create Flux.create
     Contrôle manuel de l’émission
     des événements
     Flowable.using Flux.using Gestion d’une ressource
     Flowable.fromPublisher Flux.from
     Utilisation d’un Publisher
     (Reactive Streams)
     Flowable.generate Flux.generate
     Utilisation d’un générateur de
     valeurs
     

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123. RxJava

     RxJava 2
     Reactor
     Flowable.just Flux.just
     Émission d’une valeur
     existante
     Flowable.defer Flux.defer
     Émission tardive d’un
     Observable
     Flowable.fromCallable Mono.fromCallable
     Émission à partir d’un appel
     de fonction
     Flowable.create Flux.create
     Contrôle manuel de l’émission
     des événements
     Flowable.using Flux.using Gestion d’une ressource
     Flowable.fromPublisher Flux.from
     Utilisation d’un Publisher
     (Reactive Streams)
     Flowable.generate Flux.generate
     Utilisation d’un générateur de
     valeurs
     

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124. RxJava

     RxJava 2
     Reactor
     Flowable.just Flux.just
     Émission d’une valeur
     existante
     Flowable.defer Flux.defer
     Émission tardive d’un
     Observable
     Flowable.fromCallable Mono.fromCallable
     Émission à partir d’un appel
     de fonction
     Flowable.create Flux.create
     Contrôle manuel de l’émission
     des événements
     Flowable.using Flux.using Gestion d’une ressource
     Flowable.fromPublisher Flux.from
     Utilisation d’un Publisher
     (Reactive Streams)
     Flowable.generate Flux.generate
     Utilisation d’un générateur de
     valeurs
     

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125. exemple
     d’encapsulation
     

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126. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis")

     private String redis() throws InterruptedException {

     CountDownLatch latch = new CountDownLatch(1);

     AtomicReference result = new AtomicReference<>();

     this.connection.subscribe((message, pattern) -> {

     result.set(message.toString());

     latch.countDown();

     }, TOPIC_NAME);

     latch.await();

     return result.get();

     }
     }
     

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127. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis")

     private String redis() throws InterruptedException {

     CountDownLatch latch = new CountDownLatch(1);

     AtomicReference result = new AtomicReference<>();

     this.connection.subscribe((message, pattern) -> {

     result.set(message.toString());

     latch.countDown();

     }, TOPIC_NAME);

     latch.await();

     return result.get();

     }
     }
     Écoute de Redis
     

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128. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis")

     private String redis() throws InterruptedException {

     CountDownLatch latch = new CountDownLatch(1);

     AtomicReference result = new AtomicReference<>();

     this.connection.subscribe((message, pattern) -> {

     result.set(message.toString());

     latch.countDown();

     }, TOPIC_NAME);

     latch.await();

     return result.get();

     }
     }
     Code de synchronisation
     Code de synchronisation
     

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129. Étape 1
     Encapsuler
     

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130. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis")

     private String redis() throws InterruptedException {

     

     String result = Flowable.create(sub -> {

     this.connection.subscribe((message, pattern) -> {

     sub.onNext(message.toString());

     sub.onComplete();

     }, TOPIC_NAME);

     }, BackpressureStrategy.BUFFER)

     .blockingFirst();

     return result;

     }
     }
     

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131. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis")

     private String redis() throws InterruptedException {

     

     String result = Flowable.create(sub -> {

     this.connection.subscribe((message, pattern) -> {

     sub.onNext(message.toString());

     sub.onComplete();

     }, TOPIC_NAME);

     }, BackpressureStrategy.BUFFER)

     .blockingFirst();

     return result;

     }
     }
     Encapsulation
     Synchronisation
     Contract Reactive
     

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132. Étape 2
     Asynchrone
     

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133. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis")

     private DeferredResult redis() throws InterruptedException {

     

     DeferredResult result = new DeferredResult<>(10_000l);

     

     Flowable.create(sub -> {

     this.connection.subscribe((message, pattern) -> {

     sub.onNext(message.toString());

     sub.onComplete();

     }, TOPIC_NAME);

     }, BackpressureStrategy.BUFFER)

     .subscribe(result::setResult);

     

     return result;

     }
     

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134. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis")

     private DeferredResult redis() throws InterruptedException {

     

     DeferredResult result = new DeferredResult<>(10_000l);

     

     Flowable.create(sub -> {

     this.connection.subscribe((message, pattern) -> {

     sub.onNext(message.toString());

     sub.onComplete();

     }, TOPIC_NAME);

     }, BackpressureStrategy.BUFFER)

     .subscribe(result::setResult);

     

     return result;

     } Résultat tardif
     Utilisation de DeferredResult
     

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135. Étape 3
     Reactive Streams
     

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136. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis", produces = MediaType.TEXT_EVENT_STREAM_VALUE)

     private Flux redis() throws InterruptedException {

     

     Flowable rxjava = Flowable.create(sub -> {

     this.connection.subscribe((message, pattern) -> sub.onNext(message.toString()),
     TOPIC_NAME);

     }, BackpressureStrategy.BUFFER);

     

     return Flux.defer(() -> rxjava);

     }
     }
     

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137. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis", produces = MediaType.TEXT_EVENT_STREAM_VALUE)

     private Flux redis() throws InterruptedException {

     

     Flowable rxjava = Flowable.create(sub -> {

     this.connection.subscribe((message, pattern) -> sub.onNext(message.toString()),
     TOPIC_NAME);

     }, BackpressureStrategy.BUFFER);

     

     return Flux.defer(() -> rxjava);

     }
     }
     RxJava 2 → Flux
     Flux → SSE
     

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138. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis", produces = MediaType.TEXT_EVENT_STREAM_VALUE)

     private Publisher redis() throws InterruptedException {

     return Flowable.create(sub -> {

     this.connection.subscribe((message, pattern) -> sub.onNext(message.toString()),
     TOPIC_NAME);

     }, BackpressureStrategy.BUFFER);

     

     }
     

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139. @RestController

     public class HelloController {

     

     private static final byte[] TOPIC_NAME = "topic".getBytes();

     

     @RequestMapping(value = "/redis", produces = MediaType.TEXT_EVENT_STREAM_VALUE)

     private Publisher redis() throws InterruptedException {

     return Flowable.create(sub -> {

     this.connection.subscribe((message, pattern) -> sub.onNext(message.toString()),
     TOPIC_NAME);

     }, BackpressureStrategy.BUFFER);

     

     }
     Publisher
     

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140. View Slide

141. Migrer son application
     Reactive
     depuis RxJava
     

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142. rx.Observable io.reactivex.Observable
     rx.Single
     rx.Completable io.reactivex.Completable
     io.reactivex.Single
     RxJava RxJava 2
     package différent
     

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143. RxJavaInterop.toV2Observable(rx.Observable.just(1, 2, 3))

     .firstElement()

     .subscribe();

     

     RxJavaInterop.toV1Observable(io.reactivex.Observable.just(1, 2, 3), 

     BackpressureStrategy.DROP)

     .first()

     .subscribe();
     https://github.com/akarnokd/RxJava2Interop
     RxJava → RxJava 2
     RxJava 2 → RxJava
     

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144. Reactive Streams
     n’ acceptent pas
     de valeur null
     (sauf Maybe.fromCallable)
     

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145. Observable.just(null);

     

     Single.just(null);

     

     Observable.fromCallable(() -> null)

     .subscribe(System.out::println, Throwable::printStackTrace);

     

     Observable.just(1).map(v -> null)

     .subscribe(System.out::println, Throwable::printStackTrace);
     NullPointerException
     NullPointerException
     NullPointerException
     N
     ullPointerException
     

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146. Reactor se base sur
     Java 8 tandis que
     RxJava 2 utilise Java 6
     

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147. Reactor se base sur
     Java 8 tandis que
     RxJava 2 utilise Java 6
     

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148. Flux.interval(Duration.of(1, ChronoUnit.SECONDS))

     .map(i -> String.valueOf(i))

     .subscribe();
     

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149. Flux.interval(Duration.of(1, ChronoUnit.SECONDS))

     .map(i -> String.valueOf(i))

     .subscribe();
     java.time.Duration
     java.util.Function
     

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150. Flux.fromStream(stream)

     .map(i -> "value -> " + String.valueOf(i))

     .toStream()

     .forEach(System.out::println);
     

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151. Flux.fromStream(stream)

     .map(i -> "value -> " + String.valueOf(i))

     .toStream()

     .forEach(System.out::println);
     Conversion Stream Java 8 en Flux
     Conversion Flux en Stream Java 8
     

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152. Reactor se base sur
     Java 8 tandis que
     RxJava 2 utilise Java 6
     

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153. Reactor se base sur
     Java 8 tandis que
     RxJava 2 utilise Java 6
     

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154. rx.Action1
     rx.Func1
     RxJava RxJava 2
     rx.Func2
     rx.Func3
     rx.Action2
     io.reactivex.functions.Consumer
     io.reactivex.functions.Function
     io.reactivex.functions.BiFunction
     io.reactivex.functions.Function3
     io.reactivex.functions.BiConsumer
     Suivre les conventions Java 8
     

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155. Observable.interval(1, TimeUnit.SECONDS)

     .map(i -> String.valueOf(i))

     .subscribe();
     

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156. Observable.interval(1, TimeUnit.SECONDS)

     .map(i -> String.valueOf(i))

     .subscribe();
     java.util.concurrent.TimeUnit
     

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157. Observable.interval(1, TimeUnit.SECONDS)

     .map(i -> String.valueOf(i))

     .subscribe();
     io.reactivex.functions.Function
     

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158. Asynchrone
     gestion de contexte d’exécution
     

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159. Schedulers
     Rethink cette partie là
     

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160. Scheduler 

     (Pool de Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

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161. Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     Scheduler 

     (Pool de Thread)
     

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162. Tâche 1 Tâche 2
     Tâche 3
     Tâche 4
     Scheduler 

     (Pool de Thread)
     

     View Slide

163. Tâche 1 Tâche 2
     Tâche 3
     Tâche 4
     Scheduler 

     (Pool de Thread)
     

     View Slide

164. Tâche 1 Tâche 2
     Tâche 3 Tâche 4
     Scheduler 

     (Pool de Thread)
     

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165. Tâche 1
     Tâche 2
     Tâche 3 Tâche 4
     Scheduler 

     (Pool de Thread)
     

     View Slide

166. Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     Scheduler 

     (Pool de Thread)
     

     View Slide

167. Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     Scheduler 

     (Pool de Thread)
     

     View Slide

168. Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     Scheduler 

     (Pool de Thread)
     

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169. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

     View Slide

170. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

     View Slide

171. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

     View Slide

172. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

     View Slide

173. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

     View Slide

174. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

     View Slide

175. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

     View Slide

176. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

     View Slide

177. Scheduler 

     (Single Thread)
     Tâche 1
     Tâche 2
     Tâche 3
     Tâche 4
     

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178. java.lang.IllegalStateException: 

     Not on the main thread
     NetworkOnMainThreadException
     

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179. JavaFx.fromClick(btn) 

     .observeOn(Schedulers.io())

     .switchMap(evt -> remoteApi.getData())

     .observeOn(Schedulers.computation())

     .flatMap(data -> intensiveComputation(data))

     .observeOn(javaFx())

     .doOnNext(value -> btn.setText("Data: " + value)) 

     .subscribe();
     

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180. JavaFx.fromClick(btn) 

     .observeOn(Schedulers.io())

     .switchMap(evt -> remoteApi.getData())

     .observeOn(Schedulers.computation())

     .flatMap(data -> intensiveComputation(data))

     .observeOn(javaFx())

     .doOnNext(value -> btn.setText("Data: " + value)) 

     .subscribe();
     entrée/sortie
     calculs
     Thread graphique
     

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181. RxJava RxJava 2 Reactor Description
     io() io() elastic()
     Pool de Thread qui
     grossit au besoin
     computation() computation() parallel() Pool fini de Thread
     single() single() single() Pool de 1 Thread
     immediate() immediate()
     Execute la tâche
     immédiatement
     trampoline() trampoline()
     Ajoute la tâche dans
     une file d’attente
     avant de l’executer
     

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182. RxJava RxJava 2 Reactor Description
     io() io() elastic()
     Pool de Thread qui
     grossit au besoin
     computation() computation() parallel() Pool fini de Thread
     single() single() single() Pool de 1 Thread
     immediate() immediate()
     Execute la tâche
     immédiatement
     trampoline() trampoline()
     Ajoute la tâche dans
     une file d’attente
     avant de l’executer
     

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183. RxJava RxJava 2 Reactor Description
     io() io() elastic()
     Pool de Thread qui
     grossit au besoin
     computation() computation() parallel() Pool fini de Thread
     single() single() single() Pool de 1 Thread
     immediate() immediate()
     Execute la tâche
     immédiatement
     trampoline() trampoline()
     Ajoute la tâche dans
     une file d’attente
     avant de l’executer
     

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184. RxJava RxJava 2 Reactor Description
     io() io() elastic()
     Pool de Thread qui
     grossit au besoin
     computation() computation() parallel() Pool fini de Thread
     single() single() single() Pool de 1 Thread
     immediate() immediate()
     Execute la tâche
     immédiatement
     trampoline() trampoline()
     Ajoute la tâche dans
     une file d’attente
     avant de l’executer
     

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185. RxJava RxJava 2 Reactor Description
     io() io() elastic()
     Pool de Thread qui
     grossit au besoin
     computation() computation() parallel() Pool fini de Thread
     single() single() single() Pool de 1 Thread
     immediate() immediate()
     Execute la tâche
     immédiatement
     trampoline() trampoline()
     Ajoute la tâche dans
     une file d’attente
     avant de l’executer
     Absent pour votre
     bien
     

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186. RxJava RxJava 2 Reactor Description
     io() io() elastic()
     Pool de Thread qui
     grossit au besoin
     computation() computation() parallel() Pool fini de Thread
     single() single() single() Pool de 1 Thread
     immediate() immediate()
     Execute la tâche
     immédiatement
     trampoline() trampoline()
     Ajoute la tâche dans
     une file d’attente
     avant de l’executer
     

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187. Reactor
     nommage technique
     

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188. RxJava
     nommage fonctionnel
     

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189. Backpressure
     

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190. Consommateur
     ça déborde !
     

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191. Flowable.range(1, 100000)

     .subscribe(new Subscriber() {

     

     private Subscription source;

     

     @Override

     public void onSubscribe(Subscription s) {

     this.source = s;

     this.source.request(1);

     }

     

     @Override

     public void onNext(Integer o) {

     longComputation(o);

     this.source.request(1);

     }

     });
     

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192. Flowable.range(1, 100000)

     .subscribe(new Subscriber() {

     

     private Subscription source;

     

     @Override

     public void onSubscribe(Subscription s) {

     this.source = s;

     this.source.request(1);

     }

     

     @Override

     public void onNext(Integer o) {

     longComputation(o);

     this.source.request(1);

     }

     });
     Garder la référence de
     l’abonnement
     Demander l’émission des
     éléments suivants
     Demande l’émission
     des premiers
     éléments
     

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193. Flowable.range(1, 100000)

     .subscribe(new Subscriber() {

     

     private Subscription source;

     

     @Override

     public void onSubscribe(Subscription s) {

     this.source = s;

     this.source.request(1);

     }

     

     @Override

     public void onNext(Integer o) {

     longComputation(o);

     this.source.request(1);

     }

     });
     Contrôle de l’émission
     

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194. source()

     .subscribe(new Subscriber() {

     

     private Subscription source;

     

     @Override

     public void onSubscribe(Subscription s) {

     this.source = s;

     this.source.request(1);

     }

     

     @Override

     public void onNext(Integer o) {

     longComputation(o);

     this.source.request(1);

     }

     });
     Kafka JDBC
     Fichier
     

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195. La mécanique est
     identique
     avec Reactor
     (merci les Reactive Streams)
     

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196. Debug
     Rajouter stack insignifiant
     

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197. rx.exceptions.OnErrorNotImplementedException: Sequence contains too many elements
     at rx.internal.util.InternalObservableUtils$ErrorNotImplementedAction.call(InternalObservableUtils.java:
     386)
     at rx.internal.util.InternalObservableUtils$ErrorNotImplementedAction.call(InternalObservableUtils.java:
     383)
     at rx.internal.util.ActionSubscriber.onError(ActionSubscriber.java:44)
     at rx.observers.SafeSubscriber._onError(SafeSubscriber.java:153)
     at rx.observers.SafeSubscriber.onError(SafeSubscriber.java:115)
     at rx.internal.operators.OperatorSingle$ParentSubscriber.onNext(OperatorSingle.java:97)
     at rx.internal.operators.OnSubscribeRange$RangeProducer.slowPath(OnSubscribeRange.java:90)
     at rx.internal.operators.OnSubscribeRange$RangeProducer.request(OnSubscribeRange.java:68)
     at rx.Subscriber.setProducer(Subscriber.java:211)
     at rx.internal.operators.OnSubscribeRange.call(OnSubscribeRange.java:38)
     Stacktrace inexploitable
     

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198. RxJavaHooks.enableAssemblyTracking();
     […]
     Caused by: rx.exceptions.AssemblyStackTraceException: Assembly trace:
     at rx.Observable.create(Observable.java:100)
     at rx.Observable.lift(Observable.java:237)
     at rx.Observable.single(Observable.java:9330)
     at rxjava2.BasicExampleTest.stacktrace(BasicExampleTest.java:225)
     rx.Observable.range(1, 100)

     .single()

     .subscribe();
     

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199. enableTracing n’est
     pas encore supporté
     par RxJava 2
     (pour cela, il faut utiliser RxJava2Extensions)
     https://github.com/akarnokd/RxJava2Extensions
     

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200. Hooks.onOperator(providedHook -> providedHook.operatorStacktrace());

     

     Flux.just(1, 2, 3)

     .single()

     .subscribe(System.out::println, Throwable::printStackTrace);
     

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201. Hooks.onOperator(providedHook -> providedHook.operatorStacktrace());

     

     Flux.just(1, 2, 3)

     .single()

     .subscribe(System.out::println, Throwable::printStackTrace);
     

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202. Flux.range(1, 100)

     .single()

     .checkpoint("label")

     .subscribe(…);
     

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203. Flux.range(1, 100)

     .single()

     .checkpoint("label")

     .subscribe(…);
     

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204. Flux.range(1, 100)

     .single()

     .checkpoint("label")

     .subscribe(…);
     Assembly trace from producer [reactor.core.publisher.MonoSingle], described as [label] :
     reactor.core.publisher.Mono.checkpoint(Mono.java:1304)
     rxjava2.BasicExampleTest.stacktraceReactor(BasicExampleTest.java:236)
     Error has been observed by the following operator(s):
     |_ Mono.checkpoint(BasicExampleTest.java:236)
     

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205. Attention
     dégradation des
     performances !
     

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206. Performance
     

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207. Génération
     3 4 5+
     Fusion
     RxJava 2
     Reactor
     

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208. Attention
     Slides conceptuels
     

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209. Sans fusion
     

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210. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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211. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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212. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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213. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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214. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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215. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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216. Avec fusion
     

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217. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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218. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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219. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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220. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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221. Transform (
     ⬛ → ⃝ )
     Transform ( ⃝ →
     ⬛)
     

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222. La fusion
     diminue
     la consommation mémoire et
     augmente
     les performances
     

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223. for (int x = 0; x < 10_000; x++) {

     

     Observable.interval(10, TimeUnit.MILLISECONDS)

     .takeWhile(i -> take.get())

     .flatMap(i -> Observable.range(1, 100))

     .subscribe();

     }
     

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224. RxJava 2 RxJava
     Reactor
     

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225. http://akarnokd.blogspot.fr/2016/12/the-reactive-scrabble-benchmarks.html
     Stream Java 8
     RxJava 2 / Reactor
     RxJava
     Décembre 2016
     

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226. Stream Java 8
     RxJava 2 / Reactor
     RxJava
     https://twitter.com/akarnokd/status/844555409012740096
     Mars 2017
     

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227. RxJava 2 : 

     streams performants
     pour Android
     

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228. Reactor & RxJava 2 : 

     streams performants
     pour serveur web
     

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229. Ecosystème
     

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230. Communauté Sponsor
     RxJava Grande
     Anciennement Netflix

     Maintenant Community
     RxJava 2 Grande Community
     Reactor En croissance Pivotal
     

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231. RxJava RxJava 2 Reactor
     Retrofit Oui Oui Non
     RxAndroid Oui Oui Non
     Realm Oui Non Non
     Hystrix Oui Non Non
     Couchbase Oui Non Non
     MongoDB Oui Non Non
     Spring Data 2.0 Oui Non Oui
     Reactor IPC Non Non Oui
     WebFlux Non Oui Oui
     Android Spring
     

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232. RxJava RxJava 2 Reactor
     Retrofit Oui Oui Non
     RxAndroid Oui Oui Non
     Realm Oui Non Non
     Hystrix Oui Non Non
     Couchbase Oui Non Non
     MongoDB Oui Non Non
     Spring Data 2.0 Oui Non Oui
     Reactor IPC Non Non Oui
     WebFlux Non Oui Oui
     Android Spring
     

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233. We are aggressively 

     migrating our internal code to
     RxJava 2
     https://github.com/uber/AutoDispose
     

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234. RxJava RxJava 2 Reactor
     Retrofit Oui Oui Non
     RxAndroid Oui Oui Non
     Realm Oui Non Non
     Hystrix Oui Non Non
     Couchbase Oui Non Non
     MongoDB Oui Non Non
     Spring Data 2.0 Oui Non Oui
     Reactor IPC Non Non Oui
     WebFlux Non Oui Oui
     Android Spring
     genre pourquoi si tu as une stack spring se forcer a faire
     du rx2 si le support reactor est meilleur)?
     

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235. Forte inertie
     pour migrer
     

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236. Migrer vers
     RxJava 2 ou Reactor
     

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237. RxJava RxJava 2 Reactor
     Retrofit Oui Oui Non
     RxAndroid Oui Oui Non
     Realm Oui Non Non
     Hystrix Oui Non Non
     Couchbase Oui Non Non
     MongoDB Oui Non Non
     Spring Data 2.0 Oui Non Oui
     Reactor IPC Non Non Oui
     WebFlux Non Oui Oui
     Android Spring
     

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238. Spring 5 va accelerer
     l’adoption de Reactor
     

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239. View Slide

240. View Slide

241. Android
     RxJava 2
     

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242. Backend
     RxJava 2
     

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243. Spring
     Reactor
     

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244. 2017
     l’année des Reactive Streams
     

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245. Merci pour votre attention
     On reste en contact ?
     david.wursteisen@gmail.com
     @dwursteisen
     http://blog.soat.fr
     RefCard RxJava 2 bientôt disponible !
     

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