Beobachtbar ist.empty() bewirkt, dass java.util.NoSuchElementException: die Sequenz enthält keine Elemente
Ich bin mit Retrofit-2.0.0-beta2 mit RxJava 1.0.14. Ich handle Fehler dieser Art, denn ich muss zum ausführen von code in doFinally:
.onErrorResumeNext(Observable.empty());
Aber wenn ich eine http-Antwort mit einem Fehler (401 zum Beispiel) meine app stürzt ab, ohne meine Klassen in dem stack-trace. Nichts schlimmes passiert, wenn die Verwendung Observable.never
. Hier der volle stack-trace:
java.lang.IllegalStateException: Exception thrown on Scheduler.Worker thread. Add `onError` handling.
at rx.internal.schedulers.ScheduledAction.run (ScheduledAction.java:60)
at android.os.Handler.handleCallback (Handler.java:739)
at android.os.Handler.dispatchMessage (Handler.java:95)
at android.os.Looper.loop (Looper.java:135)
at android.app.ActivityThread.main (ActivityThread.java:5221)
at java.lang.reflect.Method.invoke (Unknown source)
at java.lang.reflect.Method.invoke (Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:694)
rx.exceptions.OnErrorNotImplementedException: Sequence contains no elements
at rx.Observable$27.onError (Observable.java:7535)
at rx.observers.SafeSubscriber._onError (SafeSubscriber.java:154)
at rx.observers.SafeSubscriber.onError (SafeSubscriber.java:111)
at rx.internal.operators.OperatorDoOnEach$1.onError (OperatorDoOnEach.java:70)
at rx.internal.operators.OperatorDoOnEach$1.onError (OperatorDoOnEach.java:70)
at rx.internal.operators.OperatorDoOnEach$1.onError (OperatorDoOnEach.java:70)
at rx.internal.operators.OperatorObserveOn$ObserveOnSubscriber.pollQueue (OperatorObserveOn.java:197)
at rx.internal.operators.OperatorObserveOn$ObserveOnSubscriber$2.call (OperatorObserveOn.java:170)
at rx.internal.schedulers.ScheduledAction.run (ScheduledAction.java:55)
at android.os.Handler.handleCallback (Handler.java:739)
at android.os.Handler.dispatchMessage (Handler.java:95)
at android.os.Looper.loop (Looper.java:135)
at android.app.ActivityThread.main (ActivityThread.java:5221)
at java.lang.reflect.Method.invoke (Unknown source)
at java.lang.reflect.Method.invoke (Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:694)
java.util.NoSuchElementException: Sequence contains no elements
at rx.internal.operators.OperatorSingle$ParentSubscriber.onCompleted (OperatorSingle.java:131)
at rx.internal.operators.OperatorTake$1.onCompleted (OperatorTake.java:53)
at rx.Observable$EmptyHolder$1.call (Observable.java:1077)
at rx.Observable$EmptyHolder$1.call (Observable.java:1074)
at rx.Observable.unsafeSubscribe (Observable.java:7710)
at rx.internal.operators.OperatorOnErrorResumeNextViaObservable$1.onError (OperatorOnErrorResumeNextViaObservable.java:76)
at rx.internal.operators.OperatorDoOnEach$1.onError (OperatorDoOnEach.java:70)
at rx.internal.operators.OperatorSubscribeOn$1$1$1.onError (OperatorSubscribeOn.java:71)
at rx.observers.SerializedObserver.onError (SerializedObserver.java:159)
at rx.observers.SerializedSubscriber.onError (SerializedSubscriber.java:79)
at rx.internal.operators.OperatorTakeUntil$1.onError (OperatorTakeUntil.java:49)
at rx.internal.operators.OperatorMerge$MergeSubscriber.reportError (OperatorMerge.java:239)
at rx.internal.operators.OperatorMerge$MergeSubscriber.checkTerminate (OperatorMerge.java:774)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emitLoop (OperatorMerge.java:532)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emit (OperatorMerge.java:521)
at rx.internal.operators.OperatorMerge$InnerSubscriber.onError (OperatorMerge.java:808)
at rx.Observable$ThrowObservable$1.call (Observable.java:9600)
at rx.Observable$ThrowObservable$1.call (Observable.java:9590)
at rx.Observable.unsafeSubscribe (Observable.java:7710)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext (OperatorMerge.java:231)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext (OperatorMerge.java:140)
at rx.internal.operators.OperatorMap$1.onNext (OperatorMap.java:55)
at retrofit.RxJavaCallAdapterFactory$CallOnSubscribe.call (RxJavaCallAdapterFactory.java:113)
at retrofit.RxJavaCallAdapterFactory$CallOnSubscribe.call (RxJavaCallAdapterFactory.java:88)
at rx.Observable$2.call (Observable.java:162)
at rx.Observable$2.call (Observable.java:154)
at rx.Observable$2.call (Observable.java:162)
at rx.Observable$2.call (Observable.java:154)
at rx.Observable$2.call (Observable.java:162)
at rx.Observable$2.call (Observable.java:154)
at rx.Observable.unsafeSubscribe (Observable.java:7710)
at rx.internal.operators.OperatorSubscribeOn$1$1.call (OperatorSubscribeOn.java:62)
at rx.internal.schedulers.ScheduledAction.run (ScheduledAction.java:55)
at java.util.concurrent.Executors$RunnableAdapter.call (Executors.java:422)
at java.util.concurrent.FutureTask.run (FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201 (ScheduledThreadPoolExecutor.java:152)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run (ScheduledThreadPoolExecutor.java:265)
at java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1112)
at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:587)
at java.lang.Thread.run (Thread.java:818)
Dank,
Anton
Du musst angemeldet sein, um einen Kommentar abzugeben.
Aus der stack-trace,
Dies entspricht
take(1).single()
die auch diefirst()
Bequemlichkeit Betreiber. Ich vermute, Sie sind mit dem letzteren, aber beide erfordern mindestens ein element.Mithilfe
empty()
erstellen Sie eine beobachtbare keine Elemente, die gegen den Vertrag der downstream-Betreiber. Entweder Strahlen ein Standard-Element in deronErrorResumeNext
beobachten oder ändern Sie Ihre downstream-code zur Unterstützung von streams, keine Elemente.Observable.concat(mDatabaseObs, mRetrofitObs, mLastObs).onErrorReturn(throwable -> new ArrayList<MyObject>()) .first(data -> data != null && !data.isEmpty())
Nach meinem Verständnis sollte dies nur Strahlen eine leere Liste, wenn mRetrofitObs wirft einen Fehler, den ersten finden diese leere Liste und wechseln zum nächsten.