java.lang.IllegalStateException：從不正確的線程訪問域。領域對象只能在創建它們的線程上訪問

Question

我想通過將使用領域的改造observable返回的服務調用的響應保存到本地數據庫，試圖將改造2與RxJava和領域相結合。所以我得到一個異常說Realm從不正確的線程訪問。 這裏是我的代碼：

徑1：

restApi.userEntityList() 
      .map(userEntityDataMapper::transformAllToRealm) 
      .doOnNext(userRealmModels -> { 
       if (userRealmModels != null){ 
        mRealm = Realm.getInstance(mContext); 
        mRealm.asObservable() 
          .map(realm -> mRealm.copyToRealmOrUpdate(userEntity)) 
          .subscribe(new Subscriber<Object>() { 
           @Override 
           public void onCompleted() { 

           } 

           @Override 
           public void onError(Throwable e) { 
            e.printStackTrace(); 
           } 

           @Override 
           public void onNext(Object o) { 
            Log.d("RealmManager", "user added!"); 
           } 
          }); 
       }}) 
      .map(userEntityDataMapper::transformAll) 
      .subscribeOn(Schedulers.io()) 
      .observeOn(AndroidSchedulers.mainThread()) 
      .subscribe(new Subscriber<List<User>>() { 
       @Override 
       public void onCompleted() { 
        hideViewLoading(); 
       } 

       @Override 
       public void onError(Throwable e) { 
        hideViewLoading(); 
        showErrorMessage(new DefaultErrorBundle((Exception) e)); 
        showViewRetry(); 
       } 

       @Override 
       public void onNext(List<User> users) { 
        showUsersCollectionInView(users); 
       } 
      }); 

開拓者2：

restApi.userEntityList() 
      .map(userEntityDataMapper::transformAllToRealm) 
      .doOnNext(userRealmModels -> { 
       if (userRealmModels != null) { 
        mRealm = Realm.getInstance(mContext); 
        mRealm.beginTransaction(); 
        mRealm.copyToRealmOrUpdate(userEntity); 
        mRealm.commitTransaction(); 
       } 
      }) 
      .map(userEntityDataMapper::transformAll) 
      .subscribeOn(Schedulers.io()) 
      .observeOn(AndroidSchedulers.mainThread()) 
      .subscribe(new Subscriber<List<User>>() { 
       @Override 
       public void onCompleted() { 
        hideViewLoading(); 
       } 

       @Override 
       public void onError(Throwable e) { 
        hideViewLoading(); 
        showErrorMessage(new DefaultErrorBundle((Exception) e)); 
        showViewRetry(); 
       } 

       @Override 
       public void onNext(List<User> users) { 
        showUsersCollectionInView(users); 
       } 
      }); 

的logcat：

W/System.err: java.lang.IllegalStateException: Realm access from incorrect thread. Realm objects can only be accessed on the thread they were created. 
at io.realm.BaseRealm.checkIfValid(BaseRealm.java:349) 
at io.realm.BaseRealm.commitTransaction(BaseRealm.java:291) 
at io.realm.Realm.commitTransaction(Realm.java:108) 
at com.zeyad.cleanarchitecturet.data.db.RealmManagerImpl.put(RealmManagerImpl.java:66) 
at com.zeyad.cleanarchitecturet.data.db.RealmManagerImpl.putAll(RealmManagerImpl.java:91) 
at com.zeyad.cleanarchitecturet.data.repository.datasource.CloudUserDataStore$2.call(CloudUserDataStore.java:36) 
at com.zeyad.cleanarchitecturet.data.repository.datasource.CloudUserDataStore$2.call(CloudUserDataStore.java:32) 
at rx.Observable$11.onNext(Observable.java:4445) 
at rx.internal.operators.OperatorDoOnEach$1.onNext(OperatorDoOnEach.java:80) 
at rx.internal.operators.OperatorMap$1.onNext(OperatorMap.java:54) 
at rx.internal.operators.OperatorMerge$MergeSubscriber.emitScalar(OperatorMerge.java:477) 
at rx.internal.operators.OperatorMerge$MergeSubscriber.tryEmit(OperatorMerge.java:435) 
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:228) 
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:142) 
at rx.internal.operators.OperatorMap$1.onNext(OperatorMap.java:54) 
at retrofit.RxJavaCallAdapterFactory$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$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$2.call(Observable.java:162) 
at rx.Observable$2.call(Observable.java:154) 
at rx.Observable.unsafeSubscribe(Observable.java:8098) 
at rx.internal.operators.OperatorSubscribeOn$1$1.call(OperatorSubscribeOn.java:62) 
at rx.internal.schedulers.ScheduledAction.run(ScheduledAction.java:55) 
at rx.schedulers.ExecutorScheduler$ExecutorSchedulerWorker.run(ExecutorScheduler.java:98) 
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113) 
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588) 
at java.lang.Thread.run(Thread.java:818) 
Caused by: rx.exceptions.OnErrorThrowable$OnNextValue: OnError while emitting onNext value: java.util.ArrayList.class 
at rx.exceptions.Exceptions.throwOrReport(Exceptions.java:187) 
at rx.internal.operators.OperatorDoOnEach$1.onNext(OperatorDoOnEach.java:82) 
... 29 more 

Answer 1

我發現瞭如何解決它。要將服務器響應從改進2保存到領域，然後傳遞到用戶界面。

Retrofit.Builder() 
      .baseUrl(RestApi.API_BASE_URL) 
      .client(okHttpClient) 
      .callbackExecutor(new JobExecutor()) 
      .addConverterFactory(GsonConverterFactory.create(new GsonBuilder() 
        .setExclusionStrategies(new ExclusionStrategy() { 
         @Override 
         public boolean shouldSkipField(FieldAttributes f) { 
          return f.getDeclaringClass().equals(RealmObject.class); 
         } 

         @Override 
         public boolean shouldSkipClass(Class<?> clazz) { 
          return false; 
         } 
        }).create())) 
      .addCallAdapterFactory(RxJavaCallAdapterFactory.create()) 
      .build(); 

然後：

restApi.userRealmList() 
    .doOnNext(userRealmModels -> { 
     if (userRealmModels != null) { 
      Realm realm = Realm.getInstance(mContext); 
      realm.beginTransaction(); 
      realm.copyToRealmOrUpdate(userRealmModels); 
      realm.commitTransaction(); 
      realm.close(); 
     }}) 
    .map(userEntityDataMapper::transformAll) 
    .subscribeOn(Schedulers.io()) 
    .observeOn(AndroidSchedulers.mainThread()) 
    .subscribe(new Subscriber<List<User>>() { 
     @Override 
     public void onCompleted() { 
      hideViewLoading(); 
     } 

     @Override 
     public void onError(Throwable e) { 
      hideViewLoading(); 
      showErrorMessage(new DefaultErrorBundle((Exception) e)); 
      showViewRetry(); 
     } 

     @Override 
     public void onNext(List<User> users) { 
      showUsersCollectionInView(users); 
     } 
    }); 

Answer 2

我想你已經使用主線程創建的域對象和您正在另一個或後臺線程中使用它。如果是這樣，那麼在創建它們的同一個線程中使用它們。 即

((Activity)mContext).runOnUiThread(new Runnable() { 
    @Override 
    public void run() { 
     // You code of realm goes here 
     if (userRealmModels != null) { 
       mRealm = Realm.getInstance(mContext); 
       mRealm.beginTransaction(); 
       mRealm.copyToRealmOrUpdate(userEntity); 
       mRealm.commitTransaction(); 
     } 
    } 
});