Renamed OnSubscribe/Subscriber, moved anonymous class to static class, added --stacktrace to gradle build to capture build crash

.travis.yml

@@ -18,4 +18,4 @@ before_install:
 install:
   - ./gradlew
 script:
-  - ./gradlew assembleRelease
+  - ./gradlew assembleRelease --stacktrace

app/src/main/java/acr/browser/lightning/activity/BrowserActivity.java

@@ -110,8 +110,8 @@ import acr.browser.lightning.dialog.LightningDialogBuilder;
 import acr.browser.lightning.fragment.BookmarksFragment;
 import acr.browser.lightning.fragment.TabsFragment;
 import acr.browser.lightning.object.SearchAdapter;
+import acr.browser.lightning.react.OnSubscribe;
 import acr.browser.lightning.react.Schedulers;
-import acr.browser.lightning.react.Subscriber;
 import acr.browser.lightning.receiver.NetworkReceiver;
 
 import com.anthonycr.grant.PermissionsManager;
@@ -360,7 +360,7 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
         }
 
         mTabsManager.initializeTabs(this, getIntent(), isIncognito())
-                .subscribe(new Subscriber<Void>() {
+                .subscribe(new OnSubscribe<Void>() {
                     @Override
                     public void onNext(Void item) {}
 

app/src/main/java/acr/browser/lightning/activity/IncognitoActivity.java

@@ -11,7 +11,7 @@ import android.webkit.CookieSyncManager;
 import acr.browser.lightning.R;
 import acr.browser.lightning.react.Action;
 import acr.browser.lightning.react.Observable;
-import acr.browser.lightning.react.OnSubscribe;
+import acr.browser.lightning.react.Subscriber;
 
 @SuppressWarnings("deprecation")
 public class IncognitoActivity extends BrowserActivity {
@@ -20,13 +20,13 @@ public class IncognitoActivity extends BrowserActivity {
     public Observable<Void> updateCookiePreference() {
         return Observable.create(new Action<Void>() {
             @Override
-            public void onSubscribe(@NonNull OnSubscribe<Void> onSubscribe) {
+            public void onSubscribe(@NonNull Subscriber<Void> subscriber) {
                 CookieManager cookieManager = CookieManager.getInstance();
                 if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
                     CookieSyncManager.createInstance(IncognitoActivity.this);
                 }
                 cookieManager.setAcceptCookie(mPreferences.getIncognitoCookiesEnabled());
-                onSubscribe.onComplete();
+                subscriber.onComplete();
             }
         });
     }

app/src/main/java/acr/browser/lightning/activity/MainActivity.java

@@ -11,7 +11,7 @@ import android.webkit.CookieSyncManager;
 import acr.browser.lightning.R;
 import acr.browser.lightning.react.Action;
 import acr.browser.lightning.react.Observable;
-import acr.browser.lightning.react.OnSubscribe;
+import acr.browser.lightning.react.Subscriber;
 
 @SuppressWarnings("deprecation")
 public class MainActivity extends BrowserActivity {
@@ -20,13 +20,13 @@ public class MainActivity extends BrowserActivity {
     public Observable<Void> updateCookiePreference() {
         return Observable.create(new Action<Void>() {
             @Override
-            public void onSubscribe(@NonNull OnSubscribe<Void> onSubscribe) {
+            public void onSubscribe(@NonNull Subscriber<Void> subscriber) {
                 CookieManager cookieManager = CookieManager.getInstance();
                 if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
                     CookieSyncManager.createInstance(MainActivity.this);
                 }
                 cookieManager.setAcceptCookie(mPreferences.getCookiesEnabled());
-                onSubscribe.onComplete();
+                subscriber.onComplete();
             }
         });
     }

app/src/main/java/acr/browser/lightning/activity/ReadingActivity.java

@@ -1,14 +1,12 @@
 package acr.browser.lightning.activity;
 
 import android.animation.ObjectAnimator;
-import android.app.Activity;
 import android.app.ProgressDialog;
 import android.content.DialogInterface;
 import android.content.DialogInterface.OnClickListener;
 import android.content.Intent;
 import android.graphics.PorterDuff;
 import android.graphics.drawable.ColorDrawable;
-import android.os.AsyncTask;
 import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
@@ -23,8 +21,6 @@ import android.widget.SeekBar;
 import android.widget.SeekBar.OnSeekBarChangeListener;
 import android.widget.TextView;
 
-import java.lang.ref.WeakReference;
-
 import javax.inject.Inject;
 
 import acr.browser.lightning.R;
@@ -34,8 +30,8 @@ import acr.browser.lightning.preference.PreferenceManager;
 import acr.browser.lightning.react.Action;
 import acr.browser.lightning.react.Observable;
 import acr.browser.lightning.react.OnSubscribe;
-import acr.browser.lightning.react.Schedulers;
 import acr.browser.lightning.react.Subscriber;
+import acr.browser.lightning.react.Schedulers;
 import acr.browser.lightning.react.Subscription;
 import acr.browser.lightning.reading.HtmlFetcher;
 import acr.browser.lightning.reading.JResult;
@@ -151,7 +147,7 @@ public class ReadingActivity extends AppCompatActivity {
             getSupportActionBar().setTitle(Utils.getDomainName(mUrl));
         mPageLoaderSubscription = loadPage(mUrl).subscribeOn(Schedulers.worker())
                 .observeOn(Schedulers.main())
-                .subscribe(new Subscriber<ReaderInfo>() {
+                .subscribe(new OnSubscribe<ReaderInfo>() {
                     @Override
                     public void onStart() {
                         mProgressDialog = new ProgressDialog(ReadingActivity.this);
@@ -194,20 +190,20 @@ public class ReadingActivity extends AppCompatActivity {
     private static Observable<ReaderInfo> loadPage(@NonNull final String url) {
         return Observable.create(new Action<ReaderInfo>() {
             @Override
-            public void onSubscribe(@NonNull OnSubscribe<ReaderInfo> onSubscribe) {
+            public void onSubscribe(@NonNull Subscriber<ReaderInfo> subscriber) {
                 HtmlFetcher fetcher = new HtmlFetcher();
                 try {
                     JResult result = fetcher.fetchAndExtract(url, 2500, true);
-                    onSubscribe.onNext(new ReaderInfo(result.getTitle(), result.getText()));
+                    subscriber.onNext(new ReaderInfo(result.getTitle(), result.getText()));
                 } catch (Exception e) {
-                    onSubscribe.onError(new Throwable("Encountered exception"));
+                    subscriber.onError(new Throwable("Encountered exception"));
                     e.printStackTrace();
                 } catch (OutOfMemoryError e) {
                     System.gc();
-                    onSubscribe.onError(new Throwable("Out of memory"));
+                    subscriber.onError(new Throwable("Out of memory"));
                     e.printStackTrace();
                 }
-                onSubscribe.onComplete();
+                subscriber.onComplete();
             }
         });
     }

app/src/main/java/acr/browser/lightning/activity/TabsManager.java

@@ -25,8 +25,8 @@ import acr.browser.lightning.constant.Constants;
 import acr.browser.lightning.preference.PreferenceManager;
 import acr.browser.lightning.react.Action;
 import acr.browser.lightning.react.OnSubscribe;
-import acr.browser.lightning.react.Schedulers;
 import acr.browser.lightning.react.Subscriber;
+import acr.browser.lightning.react.Schedulers;
 import acr.browser.lightning.utils.FileUtils;
 import acr.browser.lightning.react.Observable;
 import acr.browser.lightning.view.LightningView;
@@ -66,14 +66,14 @@ public class TabsManager {
                                                         final boolean incognito) {
         return Observable.create(new Action<Void>() {
             @Override
-            public void onSubscribe(@NonNull final OnSubscribe<Void> onSubscribe) {
+            public void onSubscribe(@NonNull final Subscriber<Void> subscriber) {
 
 
                 // If incognito, only create one tab, do not handle intent
                 // in order to protect user privacy
                 if (incognito && mTabList.isEmpty()) {
                     newTab(activity, null, true);
-                    onSubscribe.onComplete();
+                    subscriber.onComplete();
                     return;
                 }
 
@@ -85,7 +85,7 @@ public class TabsManager {
                 mTabList.clear();
                 mCurrentTab = null;
                 if (mPreferenceManager.getRestoreLostTabsEnabled()) {
-                    restoreLostTabs(url, activity, onSubscribe);
+                    restoreLostTabs(url, activity, subscriber);
                 }
 
             }
@@ -94,9 +94,9 @@ public class TabsManager {
     }
 
     private void restoreLostTabs(final String url, final Activity activity,
-                                 final OnSubscribe onSubscribe) {
+                                 final Subscriber subscriber) {
         restoreState().subscribeOn(Schedulers.worker())
-                .observeOn(Schedulers.main()).subscribe(new Subscriber<Bundle>() {
+                .observeOn(Schedulers.main()).subscribe(new OnSubscribe<Bundle>() {
             @Override
             public void onNext(Bundle item) {
                 LightningView tab = newTab(activity, "", false);
@@ -127,7 +127,7 @@ public class TabsManager {
                 if (mTabList.size() == 0) {
                     newTab(activity, null, false);
                 }
-                onSubscribe.onComplete();
+                subscriber.onComplete();
             }
         });
     }
@@ -331,17 +331,17 @@ public class TabsManager {
     private Observable<Bundle> restoreState() {
         return Observable.create(new Action<Bundle>() {
             @Override
-            public void onSubscribe(@NonNull OnSubscribe<Bundle> onSubscribe) {
+            public void onSubscribe(@NonNull Subscriber<Bundle> subscriber) {
                 Bundle savedState = FileUtils.readBundleFromStorage(mApp, BUNDLE_STORAGE);
                 if (savedState != null) {
                     Log.d(Constants.TAG, "Restoring previous WebView state now");
                     for (String key : savedState.keySet()) {
                         if (key.startsWith(BUNDLE_KEY)) {
-                            onSubscribe.onNext(savedState.getBundle(key));
+                            subscriber.onNext(savedState.getBundle(key));
                         }
                     }
                 }
-                onSubscribe.onComplete();
+                subscriber.onComplete();
             }
         });
     }

app/src/main/java/acr/browser/lightning/react/Action.java

@@ -4,13 +4,13 @@ import android.support.annotation.NonNull;
 
 public interface Action<T> {
     /**
-     * Should be overridden to send the onSubscribe
+     * Should be overridden to send the subscriber
-     * events such as {@link OnSubscribe#onNext(Object)}
+     * events such as {@link Subscriber#onNext(Object)}
-     * or {@link OnSubscribe#onComplete()}.
+     * or {@link Subscriber#onComplete()}.
      *
-     * @param onSubscribe the onSubscribe that is sent in
+     * @param subscriber the subscriber that is sent in
      *                   when the user of the Observable
      *                   subscribes.
      */
-    void onSubscribe(@NonNull OnSubscribe<T> onSubscribe);
+    void onSubscribe(@NonNull Subscriber<T> subscriber);
 }

app/src/main/java/acr/browser/lightning/react/Observable.java

@@ -39,7 +39,7 @@ public class Observable<T> {
      * must not be null.
      *
      * @param action the Action to perform
-     * @param <T>    the type that will be emitted to the subscriber
+     * @param <T>    the type that will be emitted to the onSubscribe
      * @return a valid non-null Observable.
      */
     @NonNull
@@ -49,7 +49,7 @@ public class Observable<T> {
     }
 
     /**
-     * Tells the Observable what Executor that the subscriber
+     * Tells the Observable what Executor that the onSubscribe
      * work should run on.
      *
      * @param subscribeExecutor the Executor to run the work on.
@@ -61,7 +61,7 @@ public class Observable<T> {
     }
 
     /**
-     * Tells the Observable what Executor the subscriber should observe
+     * Tells the Observable what Executor the onSubscribe should observe
      * the work on.
      *
      * @param observerExecutor the Executor to run to callback on.
@@ -80,7 +80,7 @@ public class Observable<T> {
         executeOnSubscriberThread(new Runnable() {
             @Override
             public void run() {
-                mAction.onSubscribe(new OnSubscribe<T>(null) {
+                mAction.onSubscribe(new Subscriber<T>() {
                     @Override
                     public void unsubscribe() {}
 
@@ -88,7 +88,7 @@ public class Observable<T> {
                     public void onComplete() {}
 
                     @Override
-                    public void start() {}
+                    public void onStart() {}
 
                     @Override
                     public void onError(@NonNull Throwable throwable) {}
@@ -102,73 +102,27 @@ public class Observable<T> {
 
     /**
      * Immediately subscribes to the Observable and starts
-     * sending events from the Observable to the {@link Subscriber}.
+     * sending events from the Observable to the {@link OnSubscribe}.
      *
-     * @param subscriber the class that wishes to receive onNext and
+     * @param onSubscribe the class that wishes to receive onNext and
-     *                   onComplete callbacks from the Observable.
+     *                    onComplete callbacks from the Observable.
      */
-    public Subscription subscribe(@NonNull Subscriber<T> subscriber) {
+    public Subscription subscribe(@NonNull OnSubscribe<T> onSubscribe) {
 
-        Preconditions.checkNonNull(subscriber);
+        Preconditions.checkNonNull(onSubscribe);
 
-        final OnSubscribe<T> onSubscribe = new OnSubscribe<T>(subscriber) {
+        final Subscriber<T> subscriber = new SubscriberImpl<>(onSubscribe, this);
 
-            @Override
+        subscriber.onStart();
-            public void unsubscribe() {
-                setSubscriber(null);
-            }
-
-            private boolean mOnCompleteExecuted = false;
-
-            @Override
-            public void onComplete() {
-                Subscriber<T> subscription = getSubscriber();
-                if (!mOnCompleteExecuted && subscription != null) {
-                    mOnCompleteExecuted = true;
-                    executeOnObserverThread(new OnCompleteRunnable<>(subscription));
-                } else {
-                    Log.e(TAG, "onComplete called more than once");
-                    throw new RuntimeException("onComplete called more than once");
-                }
-            }
-
-            @Override
-            public void start() {
-                Subscriber<T> subscription = getSubscriber();
-                executeOnObserverThread(new OnStartRunnable<>(subscription));
-            }
-
-            @Override
-            public void onError(@NonNull final Throwable throwable) {
-                Subscriber<T> subscription = getSubscriber();
-                if (!mOnCompleteExecuted && subscription != null) {
-                    mOnCompleteExecuted = true;
-                    executeOnObserverThread(new OnErrorRunnable<>(subscription, throwable));
-                } else {
-                    Log.e(TAG, "onComplete already called");
-                    throw new RuntimeException("onComplete already called");
-                }
-            }
 
-            @Override
-            public void onNext(final T item) {
-                Subscriber<T> subscription = getSubscriber();
-                if (!mOnCompleteExecuted && subscription != null) {
-                    executeOnObserverThread(new OnNextRunnable<>(subscription, item));
-                } else {
-                    Log.e(TAG, "onComplete has been already called, onNext should not be called");
-                    throw new RuntimeException("onNext should not be called after onComplete has been called");
-                }
-            }
-        };
         executeOnSubscriberThread(new Runnable() {
-
             @Override
             public void run() {
-                mAction.onSubscribe(onSubscribe);
+                mAction.onSubscribe(subscriber);
             }
         });
-        return onSubscribe;
+
+        return subscriber;
     }
 
     private void executeOnObserverThread(@NonNull Runnable runnable) {
@@ -187,55 +141,111 @@ public class Observable<T> {
         }
     }
 
+    private static class SubscriberImpl<T> implements Subscriber<T> {
+
+        @Nullable private OnSubscribe<T> mOnSubscribe;
+        @NonNull private Observable<T> mObservable;
+        private boolean mOnCompleteExecuted = false;
+
+        public SubscriberImpl(@NonNull OnSubscribe<T> onSubscribe, @NonNull Observable<T> observable) {
+            mOnSubscribe = onSubscribe;
+            mObservable = observable;
+        }
+
+        @Override
+        public void unsubscribe() {
+            mOnSubscribe = null;
+        }
+
+        @Override
+        public void onComplete() {
+            if (!mOnCompleteExecuted && mOnSubscribe != null) {
+                mOnCompleteExecuted = true;
+                mObservable.executeOnObserverThread(new OnCompleteRunnable<>(mOnSubscribe));
+            } else {
+                Log.e(TAG, "onComplete called more than once");
+                throw new RuntimeException("onComplete called more than once");
+            }
+        }
+
+        @Override
+        public void onStart() {
+            if (mOnSubscribe != null) {
+                mObservable.executeOnObserverThread(new OnStartRunnable<>(mOnSubscribe));
+            }
+        }
+
+        @Override
+        public void onError(@NonNull final Throwable throwable) {
+            if (!mOnCompleteExecuted && mOnSubscribe != null) {
+                mOnCompleteExecuted = true;
+                mObservable.executeOnObserverThread(new OnErrorRunnable<>(mOnSubscribe, throwable));
+            } else {
+                Log.e(TAG, "onComplete already called");
+                throw new RuntimeException("onComplete already called");
+            }
+        }
+
+        @Override
+        public void onNext(final T item) {
+            if (!mOnCompleteExecuted && mOnSubscribe != null) {
+                mObservable.executeOnObserverThread(new OnNextRunnable<>(mOnSubscribe, item));
+            } else {
+                Log.e(TAG, "onComplete has been already called, onNext should not be called");
+                throw new RuntimeException("onNext should not be called after onComplete has been called");
+            }
+        }
+    }
+
     private static class OnCompleteRunnable<T> implements Runnable {
-        private final Subscriber<T> subscriber;
+        private final OnSubscribe<T> onSubscribe;
 
-        public OnCompleteRunnable(Subscriber<T> subscriber) {this.subscriber = subscriber;}
+        public OnCompleteRunnable(OnSubscribe<T> onSubscribe) {this.onSubscribe = onSubscribe;}
 
         @Override
         public void run() {
-            subscriber.onComplete();
+            onSubscribe.onComplete();
         }
     }
 
     private static class OnNextRunnable<T> implements Runnable {
-        private final Subscriber<T> subscriber;
+        private final OnSubscribe<T> onSubscribe;
         private final T item;
 
-        public OnNextRunnable(Subscriber<T> subscriber, T item) {
+        public OnNextRunnable(OnSubscribe<T> onSubscribe, T item) {
-            this.subscriber = subscriber;
+            this.onSubscribe = onSubscribe;
             this.item = item;
         }
 
         @Override
         public void run() {
-            subscriber.onNext(item);
+            onSubscribe.onNext(item);
         }
     }
 
     private static class OnErrorRunnable<T> implements Runnable {
-        private final Subscriber<T> subscriber;
+        private final OnSubscribe<T> onSubscribe;
         private final Throwable throwable;
 
-        public OnErrorRunnable(Subscriber<T> subscriber, Throwable throwable) {
+        public OnErrorRunnable(OnSubscribe<T> onSubscribe, Throwable throwable) {
-            this.subscriber = subscriber;
+            this.onSubscribe = onSubscribe;
             this.throwable = throwable;
         }
 
         @Override
         public void run() {
-            subscriber.onError(throwable);
+            onSubscribe.onError(throwable);
         }
     }
 
     private static class OnStartRunnable<T> implements Runnable {
-        private final Subscriber<T> subscriber;
+        private final OnSubscribe<T> onSubscribe;
 
-        public OnStartRunnable(Subscriber<T> subscriber) {this.subscriber = subscriber;}
+        public OnStartRunnable(OnSubscribe<T> onSubscribe) {this.onSubscribe = onSubscribe;}
 
         @Override
         public void run() {
-            subscriber.onStart();
+            onSubscribe.onStart();
         }
     }
 }

app/src/main/java/acr/browser/lightning/react/OnSubscribe.java

@@ -3,25 +3,7 @@ package acr.browser.lightning.react;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 
-public abstract class OnSubscribe<T> implements Subscription {
+public abstract class OnSubscribe<T> {
-
-    @Nullable private Subscriber<T> mSubscriber;
-
-    public OnSubscribe(@Nullable Subscriber<T> subscriber) {
-        mSubscriber = subscriber;
-        start();
-    }
-
-    public abstract void start();
-
-    @Nullable
-    public Subscriber<T> getSubscriber() {
-        return mSubscriber;
-    }
-
-    public void setSubscriber(@Nullable Subscriber<T> subscriber) {
-        mSubscriber = subscriber;
-    }
 
     /**
      * Called when the observable
@@ -35,7 +17,13 @@ public abstract class OnSubscribe<T> implements Subscription {
      * @param throwable an optional throwable that could
      *                  be sent.
      */
-    public abstract void onError(@NonNull Throwable throwable);
+    public void onError(@NonNull Throwable throwable) {}
+
+    /**
+     * Called before the observer begins
+     * to process and emit items or complete.
+     */
+    public void onStart() {}
 
     /**
      * Called when the Observer emits an
@@ -46,14 +34,14 @@ public abstract class OnSubscribe<T> implements Subscription {
      * @param item the item that has been emitted,
      *             can be null.
      */
-    public abstract void onNext(@Nullable T item);
+    public void onNext(@Nullable T item) {}
 
     /**
      * This method is called when the observer is
      * finished sending the subscriber events. It
      * is guaranteed that no other methods will be
-     * called on the Subscriber after this method
+     * called on the OnSubscribe after this method
      * has been called.
      */
-    public abstract void onComplete();
+    public void onComplete() {}
 }

app/src/main/java/acr/browser/lightning/react/Subscriber.java

@@ -3,7 +3,17 @@ package acr.browser.lightning.react;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
 
-public abstract class Subscriber<T> {
+public interface Subscriber<T> extends Subscription {
+
+    /**
+     * Called immediately upon subscribing
+     * and before the Observable begins
+     * emitting items. This should not be
+     * called by the creator of the Observable
+     * and is rather called internally by the
+     * Observable class itself.
+     */
+    void onStart();
 
     /**
      * Called when the observable
@@ -17,13 +27,7 @@ public abstract class Subscriber<T> {
      * @param throwable an optional throwable that could
      *                  be sent.
      */
-    public void onError(@NonNull Throwable throwable) {}
+    void onError(@NonNull Throwable throwable);
-
-    /**
-     * Called before the observer begins
-     * to process and emit items or complete.
-     */
-    public void onStart() {}
 
     /**
      * Called when the Observer emits an
@@ -34,14 +38,14 @@ public abstract class Subscriber<T> {
      * @param item the item that has been emitted,
      *             can be null.
      */
-    public void onNext(@Nullable T item) {}
+    void onNext(@Nullable T item);
 
     /**
      * This method is called when the observer is
      * finished sending the subscriber events. It
      * is guaranteed that no other methods will be
-     * called on the Subscriber after this method
+     * called on the OnSubscribe after this method
      * has been called.
      */
-    public void onComplete() {}
+    void onComplete();
 }

app/src/main/java/acr/browser/lightning/view/LightningView.java

@@ -55,8 +55,8 @@ import acr.browser.lightning.preference.PreferenceManager;
 import acr.browser.lightning.react.Action;
 import acr.browser.lightning.react.Observable;
 import acr.browser.lightning.react.Schedulers;
-import acr.browser.lightning.react.OnSubscribe;
 import acr.browser.lightning.react.Subscriber;
+import acr.browser.lightning.react.OnSubscribe;
 import acr.browser.lightning.utils.ProxyUtils;
 import acr.browser.lightning.utils.ThemeUtils;
 import acr.browser.lightning.utils.UrlUtils;
@@ -375,7 +375,7 @@ public class LightningView {
 
         getPathObservable("appcache")
                 .subscribeOn(Schedulers.worker())
-                .subscribe(new Subscriber<File>() {
+                .subscribe(new OnSubscribe<File>() {
                     @Override
                     public void onNext(File item) {
                         settings.setAppCachePath(item.getPath());
@@ -387,7 +387,7 @@ public class LightningView {
 
         getPathObservable("geolocation")
                 .subscribeOn(Schedulers.worker())
-                .subscribe(new Subscriber<File>() {
+                .subscribe(new OnSubscribe<File>() {
                     @Override
                     public void onNext(File item) {
                         settings.setGeolocationDatabasePath(item.getPath());
@@ -399,7 +399,7 @@ public class LightningView {
 
         getPathObservable("databases")
                 .subscribeOn(Schedulers.worker())
-                .subscribe(new Subscriber<File>() {
+                .subscribe(new OnSubscribe<File>() {
                     @Override
                     public void onNext(File item) {
                         if (API < Build.VERSION_CODES.KITKAT) {
@@ -417,10 +417,10 @@ public class LightningView {
     private Observable<File> getPathObservable(final String subFolder) {
         return Observable.create(new Action<File>() {
             @Override
-            public void onSubscribe(@NonNull OnSubscribe<File> onSubscribe) {
+            public void onSubscribe(@NonNull Subscriber<File> subscriber) {
                 File file = BrowserApp.get(mActivity).getDir(subFolder, 0);
-                onSubscribe.onNext(file);
+                subscriber.onNext(file);
-                onSubscribe.onComplete();
+                subscriber.onComplete();
             }
         });
     }