Десериализовать список пользовательских объектов из файла json с помощью Reactive X на Android (RxJava, Kotlin) - PullRequest
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Десериализовать список пользовательских объектов из файла json с помощью Reactive X на Android (RxJava, Kotlin)

0 голосов
/ 04 октября 2018

Я работаю с Reactive X на Android.

Когда я вызываю эту наблюдаемую: 

fun getTalks() : Observable<List<Talk>> {
    return Observable.create<List<Talk>> {
        val text = resources.openRawResource(R.raw.sample).bufferedReader().use { it.readText() }
        val mapper = jacksonObjectMapper()
        mapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
        mapper.readValue(text)
    }
}

A получаю ошибку во время выполнения 

2018-10-04 15:28:19.314 28269-28269/io.bdx.speaktimer W/Java7Support: Unable to load JDK7 types (annotations, java.nio.file.Path): no Java7 support added
2018-10-04 15:28:19.421 28269-28290/io.bdx.speaktimer E/TalksActivity: com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot deserialize instance of `kotlin.Unit` out of START_ARRAY token
 at [Source: (StringReader); line: 1, column: 1]
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err: io.reactivex.exceptions.CompositeException: 1 exceptions occurred. 
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.internal.observers.LambdaObserver.onError(LambdaObserver.java:80)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.checkTerminated(ObservableObserveOn.java:281)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.drainNormal(ObservableObserveOn.java:172)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.internal.operators.observable.ObservableObserveOn$ObserveOnObserver.run(ObservableObserveOn.java:255)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.internal.schedulers.ScheduledRunnable.run(ScheduledRunnable.java:66)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.internal.schedulers.ScheduledRunnable.call(ScheduledRunnable.java:57)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at java.util.concurrent.FutureTask.run(FutureTask.java:266)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:301)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at java.lang.Thread.run(Thread.java:764)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:   ComposedException 1 :
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot deserialize instance of `kotlin.Unit` out of START_ARRAY token
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:  at [Source: (StringReader); line: 1, column: 1]
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.fasterxml.jackson.databind.DeserializationContext.reportInputMismatch(DeserializationContext.java:1343)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.fasterxml.jackson.databind.DeserializationContext.handleUnexpectedToken(DeserializationContext.java:1139)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.fasterxml.jackson.databind.DeserializationContext.handleUnexpectedToken(DeserializationContext.java:1093)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromArray(BeanDeserializerBase.java:1461)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeOther(BeanDeserializer.java:185)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:161)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4013)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3023)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.bdx.speaktimer.TalksActivity$getTalks$1.subscribe(TalksActivity.kt:108)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.internal.operators.observable.ObservableCreate.subscribeActual(ObservableCreate.java:40)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.Observable.subscribe(Observable.java:12090)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.internal.operators.observable.ObservableSubscribeOn$SubscribeTask.run(ObservableSubscribeOn.java:96)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at io.reactivex.android.schedulers.HandlerScheduler$ScheduledRunnable.run(HandlerScheduler.java:119)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at android.os.Handler.handleCallback(Handler.java:790)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:99)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at android.os.Looper.loop(Looper.java:164)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at android.app.ActivityThread.main(ActivityThread.java:6494)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at java.lang.reflect.Method.invoke(Native Method)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
2018-10-04 15:28:19.423 28269-28290/io.bdx.speaktimer W/System.err:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)

Вот мой файл sample.json 

[
{
    "@class": "voxxrin.companion.domain.Presentation",
    "creationDate": null,
    "updateDate": "2018-09-24T21:13:16.567Z",
    "eventId": "bdxio18",
    "title": "Faut-il pousser mémé dans les applis ?",
    "summary": "<p>Je me présente Arthur Retrou - UX Designer. J'adore ma grand-mère pourtant je ne compte plus les appels pour l'aider à démarrer un Skype. En effet, nos parents et grand-parents investissent de plus en plus les applications, mais pas sans difficultés.\nÀ travers la création de plusieurs interfaces pour personnes âgées, je me suis confronté aux problématiques de cette silver économie. Avec des conseils simples et des astuces de design applicables à tout types de projets, je dévoile non sans humour les secrets pour concevoir des maquettes ergonomiques et adaptées.</p>\n",
    "speakers": [
        {
            "@class": "voxxrin.companion.domain.Speaker",
            "creationDate": null,
            "updateDate": "2018-09-24T21:13:12.966Z",
            "eventId": "bdxio18",
            "name": "Arthur Retrou",
            "firstName": "Arthur",
            "lastName": "Retrou",
            "company": "Dernier Cri",
            "bio": "Arthur Retrou, designer UX chez Dernier Cri. J'habite Lille et j'adore les barbecues, la paëlla, la pâte à prout et les festoches !",
            "avatarUrl": "https://scontent-cdg2-1.xx.fbcdn.net/v/t31.0-8/19055828_10212723864355964_5048654608666975793_o.jpg?_nc_cat=0&oh=815b0264049195fc01fa468831ea4883&oe=5C0AD6A9",
            "twitterId": "@derniercriio",
            "uuid": "c00a15663283cc47dea309484913dd47c5c7b93c",
            "_id": "5ba95365e4b0b618af601b1b"
        }
    ],
    "location": {
        "@class": "voxxrin.companion.domain.Room",
        "creationDate": null,
        "updateDate": "2018-09-24T21:13:10.855Z",
        "eventId": "bdxio18",
        "name": "N/C",
        "fullName": "N/C",
        "_id": "5ba95365e4b0b618af601b19"
    },
    "from": "2018-11-09T09:00:00.000Z",
    "to": "2018-11-09T10:00:00.000Z",
    "kind": "Conference",
    "externalId": "IZA-1897",
    "favorite": false,
    "reminded": false,
    "favoriteCount": 3,
    "remindMeCount": 2,
    "releasedContents": [],
    "_id": "5ba95366e4b0b618af601b50"
},
{
    "@class": "voxxrin.companion.domain.Presentation",
    "creationDate": null,
    "updateDate": "2018-09-24T21:13:16.685Z",
    "eventId": "bdxio18",
    "title": "Développeurs, n'estimez plus vos tâches ! #noEstimates",
    "summary": "<p>On le sait tous, estimer est à la fois difficile et coûteux et combien de fois vos tâches ont pris plus de temps que prévues? L'estimation est aujourd'hui l'une des méthodes de prédilection pour la prise de décision ainsi que l'évaluation des dates de release de nos projets... mais aujourd'hui il existe une alternative: ne plus estimer ses tâches!</p>\n<p>Venez découvrir ce retour d'expérience sur la mise en place du #noEstimates sur une équipe de développement depuis plus d'un an. Vous verrez quelles sont les clés ainsi que les outils nécessaires à sa mise en place.</p>\n",
    "speakers": [
        {
            "@class": "voxxrin.companion.domain.Speaker",
            "creationDate": null,
            "updateDate": "2018-09-24T21:13:13.197Z",
            "eventId": "bdxio18",
            "name": "Julien Topçu",


...


            "firstName": "Elvina",
            "lastName": "Valieva",
            "company": "PeopleDoc",
            "bio": "Loves JavaScript and Open Source.",
            "avatarUrl": "https://avatars2.githubusercontent.com/u/8288415?s=400&u=2886b74b0c6ad5838fa885a7980d90f749f830a5&v=4",
            "twitterId": "elvinanananana",
            "uuid": "df03db8f7736c82c3e7b35efffb9b9e73f857e33",
            "_id": "5ba95366e4b0b618af601b4f"
        }
    ],
    "location": {
        "@class": "voxxrin.companion.domain.Room",
        "creationDate": null,
        "updateDate": "2018-09-24T21:13:10.855Z",
        "eventId": "bdxio18",
        "name": "N/C",
        "fullName": "N/C",
        "_id": "5ba95365e4b0b618af601b19"
    },
    "from": "2018-11-09T19:00:00.000Z",
    "to": "2018-11-09T20:00:00.000Z",
    "kind": "Lightning talk",
    "externalId": "OWS-5521",
    "favorite": false,
    "reminded": false,
    "favoriteCount": 2,
    "remindMeCount": 1,
    "releasedContents": [],
    "_id": "5ba95366e4b0b618af601b7a"
}
]

Я видел этот ответ https://stackoverflow.com/a/50492616/2683000, который советует обернуть мой контент внутри объекта, но я не могу, потому что я только читаю файлы.

Есть идеи?

РЕДАКТИРОВАТЬ

Список переговоров (List<Talk>) представляет собой список этого объекта: 

import java.io.Serializable

data class Talk(
    val eventId: String,
    val title: String,
    val summary: String,
    val from: String,
    val to: String
) : Serializable

1 Ответ

0 голосов
/ 13 октября 2018

Я наконец нашел решение.

Проблема заключалась в том, чтобы сказать Джексону, что именно следует ожидать с typeFactory.

Вот как десериализовать ArrayList пользовательских объектов: 

val text = resources.openRawResource(R.raw.sample).bufferedReader().use { it.readText() }
val typeFactory = mapper.typeFactory
val collectionType = typeFactory.constructCollectionType(ArrayList::class.java, Talk::class.java)
val resultList = mapper.readValue<List<Talk>>(text, collectionType)
...