Android Studio 3.0.0-beta1——NoClassDefFoundError

'com.android.tools.build:gradle:3.0.0-beta1'

java.lang.IllegalStateException: Fatal Exception thrown on Scheduler.Worker thread.
    at rx.android.schedulers.LooperScheduler$ScheduledAction.run(LooperScheduler.java:114)
    at android.os.Handler.handleCallback(Handler.java:746)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:148)
    at android.app.ActivityThread.main(ActivityThread.java:5443)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
    Caused by: rx.exceptions.OnErrorFailedException: Error occurred when trying to propagate error to Observer.onError
    at rx.observers.SafeSubscriber._onError(SafeSubscriber.java:187)
    at rx.observers.SafeSubscriber.onError(SafeSubscriber.java:115)
    at rx.internal.operators.OperatorObserveOn$ObserveOnSubscriber.checkTerminated(OperatorObserveOn.java:273)
    at rx.internal.operators.OperatorObserveOn$ObserveOnSubscriber.call(OperatorObserveOn.java:216)
    at rx.android.schedulers.LooperScheduler$ScheduledAction.run(LooperScheduler.java:107)
    at android.os.Handler.handleCallback(Handler.java:746) 
    at android.os.Handler.dispatchMessage(Handler.java:95) 
    at android.os.Looper.loop(Looper.java:148) 
    at android.app.ActivityThread.main(ActivityThread.java:5443) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 
    Caused by: rx.exceptions.CompositeException: 2 exceptions occurred. 
    at rx.observers.SafeSubscriber._onError(SafeSubscriber.java:187) 
    at rx.observers.SafeSubscriber.onError(SafeSubscriber.java:115) 
    at rx.internal.operators.OperatorObserveOn$ObserveOnSubscriber.checkTerminated(OperatorObserveOn.java:273) 
    at rx.internal.operators.OperatorObserveOn$ObserveOnSubscriber.call(OperatorObserveOn.java:216) 
    at rx.android.schedulers.LooperScheduler$ScheduledAction.run(LooperScheduler.java:107) 
    at android.os.Handler.handleCallback(Handler.java:746) 
    at android.os.Handler.dispatchMessage(Handler.java:95) 
    at android.os.Looper.loop(Looper.java:148) 
    at android.app.ActivityThread.main(ActivityThread.java:5443) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 
    Caused by: rx.exceptions.CompositeException$CompositeExceptionCausalChain: Chain of Causes for CompositeException In Order Received =>
    at android.util.Log.getStackTraceString(Log.java:522)
    at com.android.internal.os.RuntimeInit.Clog_e(RuntimeInit.java:61)
    at com.android.internal.os.RuntimeInit.-wrap0(RuntimeInit.java)
    at com.android.internal.os.RuntimeInit$UncaughtHandler.uncaughtException(RuntimeInit.java:86)
    at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:693)
    at java.lang.ThreadGroup.uncaughtException(ThreadGroup.java:690)
    at rx.android.schedulers.LooperScheduler$ScheduledAction.run(LooperScheduler.java:118)
    at android.os.Handler.handleCallback(Handler.java:746) 
    at android.os.Handler.dispatchMessage(Handler.java:95) 
    at android.os.Looper.loop(Looper.java:148) 
    at android.app.ActivityThread.main(ActivityThread.java:5443) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:728) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 
    Caused by: retrofit2.adapter.rxjava.HttpException: HTTP 401 Unauthorized
    at retrofit2.adapter.rxjava.OperatorMapResponseToBodyOrError$1.onNext(OperatorMapResponseToBodyOrError.java:43)
    at retrofit2.adapter.rxjava.OperatorMapResponseToBodyOrError$1.onNext(OperatorMapResponseToBodyOrError.java:38)
    at retrofit2.adapter.rxjava.RxJavaCallAdapterFactory$RequestArbiter.request(RxJavaCallAdapterFactory.java:173)
    at rx.internal.operators.OperatorSubscribeOn$SubscribeOnSubscriber$1.request(OperatorSubscribeOn.java:109)
    at rx.Subscriber.setProducer(Subscriber.java:211)
    at rx.internal.operators.OperatorSubscribeOn$SubscribeOnSubscriber.setProducer(OperatorSubscribeOn.java:105)
    at rx.Subscriber.setProducer(Subscriber.java:205)
    at retrofit2.adapter.rxjava.RxJavaCallAdapterFactory$CallOnSubscribe.call(RxJavaCallAdapterFactory.java:152)
    at retrofit2.adapter.rxjava.RxJavaCallAdapterFactory$CallOnSubscribe.call(RxJavaCallAdapterFactory.java:138)
    at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
    at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
    at rx.Observable.unsafeSubscribe(Observable.java:10346)
    at rx.internal.operators.OperatorSubscribeOn$SubscribeOnSubscriber.call(OperatorSubscribeOn.java:100)
    at rx.internal.schedulers.CachedThreadScheduler$EventLoopWorker$1.call(CachedThreadScheduler.java:230)
    at rx.internal.schedulers.ScheduledAction.run(ScheduledAction.java:55)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:423)
    at java.util.concurrent.FutureTask.run(FutureTask.java:237)
    at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
    at java.lang.Thread.run(Thread.java:818)
    Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Lcom/google/devtools/build/android/desugar/runtime/ThrowableExtension;

• 所有错误处理程序都已针对RxJava调用进行了适当设置。
• Android sdk构建工具v26.0.1
• 尝试清洁、重建等