Code improvements

* Replace unchecked casts with checked casts
 * remove Utility.finViewById
 * Fix return activity checking
 * Create UserAction enum
 * Fix typos
 * Add instrumented test for error info
 * ErrorInfo make fields final
 * Log exception using logger
 * Add inherited annotations
 * Resolve deprecation warnings
 * Remove unused methods from utility
 * Reformat code
 * Remove unused methods from Utility and improve getFileExt
 * Create OnScrollBelowItemsListener

.github/CONTRIBUTING.md

@@ -5,7 +5,7 @@ READ THIS GUIDELINES CAREFULLY BEFORE CONTRIBUTING.
 
 ## Crash reporting
 
-Do not report crashes in the GitHub issue tracker. NewPipe has an automated crash report system that will ask you to send a report if a crash occures.
+Do not report crashes in the GitHub issue tracker. NewPipe has an automated crash report system that will ask you to send a report if a crash occurs.
 
 ## Issue reporting/feature request
 

app/build.gradle

@@ -10,6 +10,8 @@ android {
         targetSdkVersion 25
         versionCode 35
         versionName "0.9.8"
+
+        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }
     buildTypes {
         release {
@@ -31,6 +33,11 @@ android {
 }
 
 dependencies {
+    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2') {
+        exclude module: 'support-annotations'
+    }
+
+
     testCompile 'junit:junit:4.12'
     testCompile 'org.mockito:mockito-core:1.10.19'
     testCompile 'org.json:json:20160810'

app/src/androidTest/java/org/schabi/newpipe/report/ErrorInfoTest.java

@@ -0,0 +1,37 @@
+package org.schabi.newpipe.report;
+
+import android.os.Parcel;
+import android.support.test.filters.LargeTest;
+import android.support.test.runner.AndroidJUnit4;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.schabi.newpipe.R;
+import org.schabi.newpipe.report.ErrorActivity.ErrorInfo;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Instrumented tests for {@link ErrorInfo}
+ */
+@RunWith(AndroidJUnit4.class)
+@LargeTest
+public class ErrorInfoTest {
+
+    @Test
+    public void errorInfo_testParcelable() {
+        ErrorInfo info = ErrorInfo.make(UserAction.USER_REPORT, "youtube", "request", R.string.general_error);
+        // Obtain a Parcel object and write the parcelable object to it:
+        Parcel parcel = Parcel.obtain();
+        info.writeToParcel(parcel, 0);
+        parcel.setDataPosition(0);
+        ErrorInfo infoFromParcel = ErrorInfo.CREATOR.createFromParcel(parcel);
+
+        assertEquals(UserAction.USER_REPORT, infoFromParcel.userAction);
+        assertEquals("youtube", infoFromParcel.serviceName);
+        assertEquals("request", infoFromParcel.request);
+        assertEquals(R.string.general_error, infoFromParcel.message);
+
+        parcel.recycle();
+    }
+}

app/src/main/java/org/schabi/newpipe/App.java

@@ -14,6 +14,7 @@ import org.acra.sender.ReportSenderFactory;
 import org.schabi.newpipe.extractor.NewPipe;
 import org.schabi.newpipe.report.AcraReportSenderFactory;
 import org.schabi.newpipe.report.ErrorActivity;
+import org.schabi.newpipe.report.UserAction;
 import org.schabi.newpipe.settings.SettingsActivity;
 import org.schabi.newpipe.util.ThemeHelper;
 
@@ -59,7 +60,7 @@ public class App extends Application {
         } catch(ACRAConfigurationException ace) {
             ace.printStackTrace();
             ErrorActivity.reportError(this, ace, null, null,
-                    ErrorActivity.ErrorInfo.make(ErrorActivity.SEARCHED,"none",
+                    ErrorActivity.ErrorInfo.make(UserAction.SEARCHED,"none",
                             "Could not initialize ACRA crash report", R.string.app_ui_crash));
         }
 

app/src/main/java/org/schabi/newpipe/ImageErrorLoadingListener.java

@@ -9,6 +9,7 @@ import com.nostra13.universalimageloader.core.listener.ImageLoadingListener;
 
 import org.schabi.newpipe.extractor.NewPipe;
 import org.schabi.newpipe.report.ErrorActivity;
+import org.schabi.newpipe.report.UserAction;
 
 /**
  * Created by Christian Schabesberger on 01.08.16.
@@ -49,7 +50,7 @@ public class ImageErrorLoadingListener implements ImageLoadingListener {
     public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
         ErrorActivity.reportError(context,
                 failReason.getCause(), null, rootView,
-                ErrorActivity.ErrorInfo.make(ErrorActivity.LOAD_IMAGE,
+                ErrorActivity.ErrorInfo.make(UserAction.LOAD_IMAGE,
                         NewPipe.getNameOfService(serviceId), imageUri,
                         R.string.could_not_load_image));
     }

app/src/main/java/org/schabi/newpipe/download/DownloadActivity.java

@@ -35,7 +35,6 @@ import us.shandian.giga.service.DownloadManagerService;
 import us.shandian.giga.ui.fragment.AllMissionsFragment;
 import us.shandian.giga.ui.fragment.MissionsFragment;
 import us.shandian.giga.util.CrashHandler;
-import us.shandian.giga.util.Utility;
 
 public class DownloadActivity extends AppCompatActivity implements AdapterView.OnItemClickListener {
 
@@ -125,11 +124,11 @@ public class DownloadActivity extends AppCompatActivity implements AdapterView.O
         // Create the view
         LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
         View v = inflater.inflate(R.layout.dialog_url, null);
-        final EditText name = Utility.findViewById(v, R.id.file_name);
+        final EditText name = (EditText) v.findViewById(R.id.file_name);
-        final TextView tCount = Utility.findViewById(v, R.id.threads_count);
+        final TextView tCount = (TextView) v.findViewById(R.id.threads_count);
-        final SeekBar threads = Utility.findViewById(v, R.id.threads);
+        final SeekBar threads = (SeekBar) v.findViewById(R.id.threads);
-        final Toolbar toolbar = Utility.findViewById(v, R.id.toolbar);
+        final Toolbar toolbar = (Toolbar) v.findViewById(R.id.toolbar);
-        final RadioButton audioButton = (RadioButton) Utility.findViewById(v, R.id.audio_button);
+        final RadioButton audioButton = (RadioButton) v.findViewById(R.id.audio_button);
 
 
         threads.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {

app/src/main/java/org/schabi/newpipe/download/DownloadDialog.java

@@ -253,7 +253,7 @@ public class DownloadDialog extends DialogFragment implements RadioGroup.OnCheck
     }
 
     /**
-     * #143 #44 #42 #22: make shure that the filename does not contain illegal chars.
+     * #143 #44 #42 #22: make sure that the filename does not contain illegal chars.
      * This should fix some of the "cannot download" problems.
      */
     private String createFileName(String fileName) {

app/src/main/java/org/schabi/newpipe/fragments/channel/ChannelFragment.java

@@ -26,6 +26,7 @@ import org.schabi.newpipe.R;
 import org.schabi.newpipe.extractor.InfoItem;
 import org.schabi.newpipe.extractor.channel.ChannelInfo;
 import org.schabi.newpipe.fragments.BaseFragment;
+import org.schabi.newpipe.fragments.search.OnScrollBelowItemsListener;
 import org.schabi.newpipe.info_list.InfoItemBuilder;
 import org.schabi.newpipe.info_list.InfoListAdapter;
 import org.schabi.newpipe.util.Constants;
@@ -245,25 +246,14 @@ public class ChannelFragment extends BaseFragment implements ChannelExtractorWor
         });
 
         channelVideosList.clearOnScrollListeners();
-        channelVideosList.addOnScrollListener(new RecyclerView.OnScrollListener() {
+        channelVideosList.addOnScrollListener(new OnScrollBelowItemsListener() {
             @Override
-            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+            public void onScrolledDown(RecyclerView recyclerView) {
-                int pastVisiblesItems, visibleItemCount, totalItemCount;
+                if ((currentChannelWorker == null || !currentChannelWorker.isRunning()) && hasNextPage && !isLoading.get()) {
-                super.onScrolled(recyclerView, dx, dy);
-                //check for scroll down
-                if (dy > 0) {
-                    LinearLayoutManager layoutManager = (LinearLayoutManager) channelVideosList.getLayoutManager();
-
-                    visibleItemCount = layoutManager.getChildCount();
-                    totalItemCount = layoutManager.getItemCount();
-                    pastVisiblesItems = layoutManager.findFirstVisibleItemPosition();
-
-                    if ((visibleItemCount + pastVisiblesItems) >= totalItemCount && (currentChannelWorker == null || !currentChannelWorker.isRunning()) && hasNextPage && !isLoading.get()) {
                     pageNumber++;
                     loadMoreVideos();
                 }
             }
-            }
         });
 
         headerRssButton.setOnClickListener(new View.OnClickListener() {

app/src/main/java/org/schabi/newpipe/fragments/detail/VideoDetailFragment.java

@@ -61,6 +61,7 @@ import org.schabi.newpipe.player.MainVideoPlayer;
 import org.schabi.newpipe.player.PlayVideoActivity;
 import org.schabi.newpipe.player.PopupVideoPlayer;
 import org.schabi.newpipe.report.ErrorActivity;
+import org.schabi.newpipe.report.UserAction;
 import org.schabi.newpipe.util.Constants;
 import org.schabi.newpipe.util.Localization;
 import org.schabi.newpipe.util.NavigationHelper;
@@ -578,7 +579,7 @@ public class VideoDetailFragment extends BaseFragment implements StreamExtractor
             imageLoader.displayImage(info.thumbnail_url, thumbnailImageView, displayImageOptions, new SimpleImageLoadingListener() {
                 @Override
                 public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
-                    ErrorActivity.reportError(activity, failReason.getCause(), null, activity.findViewById(android.R.id.content), ErrorActivity.ErrorInfo.make(ErrorActivity.LOAD_IMAGE, NewPipe.getNameOfService(currentStreamInfo.service_id), imageUri, R.string.could_not_load_thumbnails));
+                    ErrorActivity.reportError(activity, failReason.getCause(), null, activity.findViewById(android.R.id.content), ErrorActivity.ErrorInfo.make(UserAction.LOAD_IMAGE, NewPipe.getNameOfService(currentStreamInfo.service_id), imageUri, R.string.could_not_load_thumbnails));
                 }
             });
         } else thumbnailImageView.setImageResource(R.drawable.dummy_thumbnail_dark);

app/src/main/java/org/schabi/newpipe/fragments/search/OnScrollBelowItemsListener.java

@@ -0,0 +1,33 @@
+package org.schabi.newpipe.fragments.search;
+
+import android.support.v7.widget.LinearLayoutManager;
+import android.support.v7.widget.RecyclerView;
+
+/**
+ * Recycler view scroll listener which calls the method {@link #onScrolledDown(RecyclerView)}
+ * if the view is scrolled below the last item.
+ */
+public abstract class OnScrollBelowItemsListener extends RecyclerView.OnScrollListener {
+
+    @Override
+    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+        super.onScrolled(recyclerView, dx, dy);
+        //check for scroll down
+        if (dy > 0) {
+            int pastVisibleItems, visibleItemCount, totalItemCount;
+            LinearLayoutManager layoutManager = (LinearLayoutManager) recyclerView.getLayoutManager();
+            visibleItemCount = recyclerView.getLayoutManager().getChildCount();
+            totalItemCount = recyclerView.getLayoutManager().getItemCount();
+            pastVisibleItems = layoutManager.findFirstVisibleItemPosition();
+            if ((visibleItemCount + pastVisibleItems) >= totalItemCount) {
+                onScrolledDown(recyclerView);
+            }
+        }
+    }
+
+    /**
+     * Called when the recycler view is scrolled below the last item.
+     * @param recyclerView the recycler view
+     */
+    public abstract void onScrolledDown(RecyclerView recyclerView);
+}

app/src/main/java/org/schabi/newpipe/fragments/search/SearchFragment.java

@@ -242,19 +242,10 @@ public class SearchFragment extends BaseFragment implements SuggestionWorker.OnS
     protected void initListeners() {
         super.initListeners();
         resultRecyclerView.clearOnScrollListeners();
-        resultRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
+        resultRecyclerView.addOnScrollListener(new OnScrollBelowItemsListener() {
             @Override
-            public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+            public void onScrolledDown(RecyclerView recyclerView) {
-                int pastVisiblesItems, visibleItemCount, totalItemCount;
+                if(!isLoading.get()) {
-                super.onScrolled(recyclerView, dx, dy);
-                //check for scroll down
-                if (dy > 0) {
-                    LinearLayoutManager layoutManager = (LinearLayoutManager) resultRecyclerView.getLayoutManager();
-                    visibleItemCount = resultRecyclerView.getLayoutManager().getChildCount();
-                    totalItemCount = resultRecyclerView.getLayoutManager().getItemCount();
-                    pastVisiblesItems = layoutManager.findFirstVisibleItemPosition();
-
-                    if ((visibleItemCount + pastVisiblesItems) >= totalItemCount && !isLoading.get()) {
                     pageNumber++;
                     recyclerView.post(new Runnable() {
                         @Override
@@ -265,10 +256,10 @@ public class SearchFragment extends BaseFragment implements SuggestionWorker.OnS
                     search(searchQuery, pageNumber);
                 }
             }
-            }
         });
     }
 
+
     @Override
     protected void reloadContent() {
         if (DEBUG) Log.d(TAG, "reloadContent() called");

app/src/main/java/org/schabi/newpipe/info_list/InfoListAdapter.java

@@ -155,7 +155,7 @@ public class InfoListAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolde
 
     @Override
     public void onBindViewHolder(RecyclerView.ViewHolder holder, int i) {
-        //god damen f*** ANDROID SH**
+        //god damn f*** ANDROID SH**
         if(holder instanceof InfoItemHolder) {
             if(header != null) {
                 i--;

app/src/main/java/org/schabi/newpipe/report/AcraReportSender.java

@@ -1,6 +1,7 @@
 package org.schabi.newpipe.report;
 
 import android.content.Context;
+import android.support.annotation.NonNull;
 
 import org.acra.collector.CrashReportData;
 import org.acra.sender.ReportSender;
@@ -30,9 +31,9 @@ import org.schabi.newpipe.R;
 public class AcraReportSender implements ReportSender {
 
     @Override
-    public void send(Context context, CrashReportData report) throws ReportSenderException {
+    public void send(@NonNull Context context, @NonNull CrashReportData report) throws ReportSenderException {
         ErrorActivity.reportError(context, report,
-                ErrorActivity.ErrorInfo.make(ErrorActivity.UI_ERROR,"none",
+                ErrorActivity.ErrorInfo.make(UserAction.UI_ERROR,"none",
                         "App crash, UI failure", R.string.app_ui_crash));
     }
 }

app/src/main/java/org/schabi/newpipe/report/AcraReportSenderFactory.java

@@ -1,6 +1,7 @@
 package org.schabi.newpipe.report;
 
 import android.content.Context;
+import android.support.annotation.NonNull;
 
 import org.acra.config.ACRAConfiguration;
 import org.acra.sender.ReportSender;
@@ -28,7 +29,8 @@ import org.schabi.newpipe.report.AcraReportSender;
  */
 
 public class AcraReportSenderFactory implements ReportSenderFactory {
-    public ReportSender create(Context context, ACRAConfiguration config) {
+    @NonNull
+    public ReportSender create(@NonNull Context context, @NonNull ACRAConfiguration config) {
         return new AcraReportSender();
     }
 }

app/src/main/java/org/schabi/newpipe/report/ErrorActivity.java

@@ -11,6 +11,8 @@ import android.os.Handler;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.preference.PreferenceManager;
+import android.support.annotation.Nullable;
+import android.support.annotation.StringRes;
 import android.support.design.widget.Snackbar;
 import android.support.v4.app.NavUtils;
 import android.support.v7.app.ActionBar;
@@ -71,24 +73,7 @@ public class ErrorActivity extends AppCompatActivity {
     // BUNDLE TAGS
     public static final String ERROR_INFO = "error_info";
     public static final String ERROR_LIST = "error_list";
-    // MESSAGE ID
+
-    public static final int SEARCHED = 0;
-    public static final int REQUESTED_STREAM = 1;
-    public static final int GET_SUGGESTIONS = 2;
-    public static final int SOMETHING_ELSE = 3;
-    public static final int USER_REPORT = 4;
-    public static final int LOAD_IMAGE = 5;
-    public static final int UI_ERROR = 6;
-    public static final int REQUESTED_CHANNEL = 7;
-    // MESSAGE STRING
-    public static final String SEARCHED_STRING = "searched";
-    public static final String REQUESTED_STREAM_STRING = "requested stream";
-    public static final String GET_SUGGESTIONS_STRING = "get suggestions";
-    public static final String SOMETHING_ELSE_STRING = "something";
-    public static final String USER_REPORT_STRING = "user report";
-    public static final String LOAD_IMAGE_STRING = "load image";
-    public static final String UI_ERROR_STRING = "ui error";
-    public static final String REQUESTED_CHANNEL_STRING = "requested channel";
     public static final String ERROR_EMAIL_ADDRESS = "crashreport@newpipe.schabi.org";
     public static final String ERROR_EMAIL_SUBJECT = "Exception in NewPipe " + BuildConfig.VERSION_NAME;
     Thread globIpRangeThread;
@@ -105,11 +90,11 @@ public class ErrorActivity extends AppCompatActivity {
     private TextView errorMessageView;
 
     public static void reportUiError(final AppCompatActivity activity, final Throwable el) {
-        reportError(activity, el, activity.getClass(), null, ErrorInfo.make(UI_ERROR, "none", "", R.string.app_ui_crash));
+        reportError(activity, el, activity.getClass(), null, ErrorInfo.make(UserAction.UI_ERROR, "none", "", R.string.app_ui_crash));
     }
 
     public static void reportError(final Context context, final List<Throwable> el,
-                                   final Class returnAcitivty, View rootView, final ErrorInfo errorInfo) {
+                                   final Class returnActivity, View rootView, final ErrorInfo errorInfo) {
 
         if (rootView != null) {
             Snackbar.make(rootView, R.string.error_snackbar_message, Snackbar.LENGTH_LONG)
@@ -118,7 +103,7 @@ public class ErrorActivity extends AppCompatActivity {
                         @Override
                         public void onClick(View v) {
                             ActivityCommunicator ac = ActivityCommunicator.getCommunicator();
-                            ac.returnActivity = returnAcitivty;
+                            ac.returnActivity = returnActivity;
                             Intent intent = new Intent(context, ErrorActivity.class);
                             intent.putExtra(ERROR_INFO, errorInfo);
                             intent.putExtra(ERROR_LIST, elToSl(el));
@@ -128,7 +113,7 @@ public class ErrorActivity extends AppCompatActivity {
                     }).show();
         } else {
             ActivityCommunicator ac = ActivityCommunicator.getCommunicator();
-            ac.returnActivity = returnAcitivty;
+            ac.returnActivity = returnActivity;
             Intent intent = new Intent(context, ErrorActivity.class);
             intent.putExtra(ERROR_INFO, errorInfo);
             intent.putExtra(ERROR_LIST, elToSl(el));
@@ -138,34 +123,34 @@ public class ErrorActivity extends AppCompatActivity {
     }
 
     public static void reportError(final Context context, final Throwable e,
-                                   final Class returnAcitivty, View rootView, final ErrorInfo errorInfo) {
+                                   final Class returnActivity, View rootView, final ErrorInfo errorInfo) {
         List<Throwable> el = null;
         if(e != null) {
             el = new Vector<>();
             el.add(e);
         }
-        reportError(context, el, returnAcitivty, rootView, errorInfo);
+        reportError(context, el, returnActivity, rootView, errorInfo);
     }
 
     // async call
     public static void reportError(Handler handler, final Context context, final Throwable e,
-                                   final Class returnAcitivty, final View rootView, final ErrorInfo errorInfo) {
+                                   final Class returnActivity, final View rootView, final ErrorInfo errorInfo) {
 
         List<Throwable> el = null;
         if(e != null) {
             el = new Vector<>();
             el.add(e);
         }
-        reportError(handler, context, el, returnAcitivty, rootView, errorInfo);
+        reportError(handler, context, el, returnActivity, rootView, errorInfo);
     }
 
     // async call
     public static void reportError(Handler handler, final Context context, final List<Throwable> el,
-                                   final Class returnAcitivty, final View rootView, final ErrorInfo errorInfo) {
+                                   final Class returnActivity, final View rootView, final ErrorInfo errorInfo) {
         handler.post(new Runnable() {
             @Override
             public void run() {
-                reportError(context, el, returnAcitivty, rootView, errorInfo);
+                reportError(context, el, returnActivity, rootView, errorInfo);
             }
         });
     }
@@ -232,7 +217,7 @@ public class ErrorActivity extends AppCompatActivity {
         errorInfo = intent.getParcelableExtra(ERROR_INFO);
         errorList = intent.getStringArrayExtra(ERROR_LIST);
 
-                //importand add gurumeditaion
+        // important add guru meditation
         addGuruMeditaion();
         currentTimeStamp = getCurrentTimeStamp();
 
@@ -250,7 +235,7 @@ public class ErrorActivity extends AppCompatActivity {
         });
         reportButton.setEnabled(false);
 
-        globIpRangeThread = new Thread(new IpRagneRequester());
+        globIpRangeThread = new Thread(new IpRangeRequester());
         globIpRangeThread.start();
 
         // normal bugreport
@@ -308,17 +293,30 @@ public class ErrorActivity extends AppCompatActivity {
         return text;
     }
 
+    /**
+     * Get the checked activity.
+     * @param returnActivity the activity to return to
+     * @return the casted return activity or null
+     */
+    @Nullable
+    static Class<? extends Activity> getReturnActivity(Class<?> returnActivity) {
+        Class<? extends Activity> checkedReturnActivity = null;
+        if (returnActivity != null){
+            if (Activity.class.isAssignableFrom(returnActivity)) {
+                checkedReturnActivity = returnActivity.asSubclass(Activity.class);
+            } else {
+                checkedReturnActivity = MainActivity.class;
+            }
+        }
+        return checkedReturnActivity;
+    }
+
     private void goToReturnActivity() {
-        if (returnActivity == null) {
+        Class<? extends Activity> checkedReturnActivity = getReturnActivity(returnActivity);
+        if (checkedReturnActivity == null) {
             super.onBackPressed();
         } else {
-            Intent intent;
+            Intent intent = new Intent(this, checkedReturnActivity);
-            if (returnActivity != null &&
-                    returnActivity.isAssignableFrom(Activity.class)) {
-                intent = new Intent(this, returnActivity);
-            } else {
-                intent = new Intent(this, MainActivity.class);
-            }
             intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
             NavUtils.navigateUpTo(this, intent);
         }
@@ -376,26 +374,11 @@ public class ErrorActivity extends AppCompatActivity {
         return "";
     }
 
-    private String getUserActionString(int userAction) {
+    private String getUserActionString(UserAction userAction) {
-        switch (userAction) {
+        if(userAction == null) {
-            case REQUESTED_STREAM:
-                return REQUESTED_STREAM_STRING;
-            case SEARCHED:
-                return SEARCHED_STRING;
-            case GET_SUGGESTIONS:
-                return GET_SUGGESTIONS_STRING;
-            case SOMETHING_ELSE:
-                return SOMETHING_ELSE_STRING;
-            case USER_REPORT:
-                return USER_REPORT_STRING;
-            case LOAD_IMAGE:
-                return LOAD_IMAGE_STRING;
-            case UI_ERROR:
-                return UI_ERROR_STRING;
-            case REQUESTED_CHANNEL:
-                return REQUESTED_CHANNEL_STRING;
-            default:
             return "Your description is in another castle.";
+        } else {
+            return userAction.getMessage();
         }
     }
 
@@ -444,28 +427,28 @@ public class ErrorActivity extends AppCompatActivity {
                 return new ErrorInfo[size];
             }
         };
-        public int userAction;
+        final public UserAction userAction;
-        public String request;
+        final public String request;
-        public String serviceName;
+        final public String serviceName;
-        public int message;
+        @StringRes
+        final public int message;
 
-        public ErrorInfo() {
+        private ErrorInfo(UserAction userAction, String serviceName, String request, @StringRes int message) {
+            this.userAction = userAction;
+            this.serviceName = serviceName;
+            this.request = request;
+            this.message = message;
         }
 
         protected ErrorInfo(Parcel in) {
-            this.userAction = in.readInt();
+            this.userAction = UserAction.valueOf(in.readString());
             this.request = in.readString();
             this.serviceName = in.readString();
             this.message = in.readInt();
         }
 
-        public static ErrorInfo make(int userAction, String serviceName, String request, int message) {
+        public static ErrorInfo make(UserAction userAction, String serviceName, String request, @StringRes int message) {
-            ErrorInfo info = new ErrorInfo();
+            return new ErrorInfo(userAction, serviceName, request, message);
-            info.userAction = userAction;
-            info.serviceName = serviceName;
-            info.request = request;
-            info.message = message;
-            return info;
         }
 
         @Override
@@ -475,14 +458,14 @@ public class ErrorActivity extends AppCompatActivity {
 
         @Override
         public void writeToParcel(Parcel dest, int flags) {
-            dest.writeInt(this.userAction);
+            dest.writeString(this.userAction.name());
             dest.writeString(this.request);
             dest.writeString(this.serviceName);
             dest.writeInt(this.message);
         }
     }
 
-    private class IpRagneRequester implements Runnable {
+    private class IpRangeRequester implements Runnable {
         Handler h = new Handler();
         public void run() {
             String ipRange = "none";
@@ -493,17 +476,16 @@ public class ErrorActivity extends AppCompatActivity {
                 ipRange = Parser.matchGroup1("([0-9]*\\.[0-9]*\\.)[0-9]*\\.[0-9]*", ip)
                         + "0.0";
             } catch(Throwable e) {
-                Log.d(TAG, "Error while error: could not get iprange");
+                Log.w(TAG, "Error while error: could not get iprange", e);
-                e.printStackTrace();
             } finally {
-                h.post(new IpRageReturnRunnable(ipRange));
+                h.post(new IpRangeReturnRunnable(ipRange));
             }
         }
     }
 
-    private class IpRageReturnRunnable implements Runnable {
+    private class IpRangeReturnRunnable implements Runnable {
         String ipRange;
-        public IpRageReturnRunnable(String ipRange) {
+        public IpRangeReturnRunnable(String ipRange) {
             this.ipRange = ipRange;
         }
         public void run() {

app/src/main/java/org/schabi/newpipe/report/UserAction.java

@@ -0,0 +1,26 @@
+package org.schabi.newpipe.report;
+
+/**
+ * The user actions that can cause an error.
+ */
+public enum UserAction {
+    SEARCHED("searched"),
+    REQUESTED_STREAM("requested stream"),
+    GET_SUGGESTIONS("get suggestions"),
+    SOMETHING_ELSE("something"),
+    USER_REPORT("user report"),
+    LOAD_IMAGE("load image"),
+    UI_ERROR("ui error"),
+    REQUESTED_CHANNEL("requested channel");
+
+
+    private final String message;
+
+    UserAction(String message) {
+        this.message = message;
+    }
+
+    public String getMessage() {
+        return message;
+    }
+}

app/src/main/java/org/schabi/newpipe/settings/NewPipeSettings.java

@@ -72,9 +72,7 @@ public class NewPipeSettings {
     public static String getVideoDownloadPath(Context context) {
         SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
         final String key = context.getString(R.string.download_path_key);
-        String downloadPath = prefs.getString(key, Environment.DIRECTORY_MOVIES);
+        return prefs.getString(key, Environment.DIRECTORY_MOVIES);
-
-        return downloadPath;
     }
 
     public static File getAudioDownloadFolder(Context context) {
@@ -84,9 +82,7 @@ public class NewPipeSettings {
     public static String getAudioDownloadPath(Context context) {
         SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
         final String key = context.getString(R.string.download_path_audio_key);
-        String downloadPath = prefs.getString(key, Environment.DIRECTORY_MUSIC);
+        return prefs.getString(key, Environment.DIRECTORY_MUSIC);
-
-        return downloadPath;
     }
 
     private static File getFolder(Context context, int keyID, String defaultDirectoryName) {

app/src/main/java/org/schabi/newpipe/workers/ChannelExtractorWorker.java

@@ -12,6 +12,8 @@ import org.schabi.newpipe.report.ErrorActivity;
 
 import java.io.IOException;
 
+import static org.schabi.newpipe.report.UserAction.REQUESTED_CHANNEL;
+
 /**
  * Extract {@link ChannelInfo} with {@link ChannelExtractor} from the given url of the given service
  *
@@ -67,7 +69,7 @@ public class ChannelExtractorWorker extends ExtractorWorker {
         ChannelExtractor extractor = getService().getChannelExtractorInstance(url, pageNumber);
         channelInfo = ChannelInfo.getInfo(extractor);
 
-        if (!channelInfo.errors.isEmpty()) handleErrorsDuringExtraction(channelInfo.errors, ErrorActivity.REQUESTED_CHANNEL);
+        if (!channelInfo.errors.isEmpty()) handleErrorsDuringExtraction(channelInfo.errors, REQUESTED_CHANNEL);
 
         if (callback != null && channelInfo != null && !isInterrupted()) getHandler().post(new Runnable() {
             @Override
@@ -93,7 +95,7 @@ public class ChannelExtractorWorker extends ExtractorWorker {
                 }
             });
         } else if (exception instanceof ParsingException || exception instanceof ExtractionException) {
-            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(ErrorActivity.REQUESTED_CHANNEL, getServiceName(), url, R.string.parsing_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(REQUESTED_CHANNEL, getServiceName(), url, R.string.parsing_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {
@@ -101,7 +103,7 @@ public class ChannelExtractorWorker extends ExtractorWorker {
                 }
             });
         } else {
-            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(ErrorActivity.REQUESTED_CHANNEL, getServiceName(), url, R.string.general_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(REQUESTED_CHANNEL, getServiceName(), url, R.string.general_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {

app/src/main/java/org/schabi/newpipe/workers/ExtractorWorker.java

@@ -6,6 +6,7 @@ import android.util.Log;
 import android.view.View;
 
 import org.schabi.newpipe.report.ErrorActivity;
+import org.schabi.newpipe.report.UserAction;
 
 import java.util.List;
 
@@ -59,14 +60,14 @@ public abstract class ExtractorWorker extends AbstractWorker {
      * @param errorUserAction   what action was the user performing during the error.
      *                          (One of the {@link ErrorActivity}.REQUEST_* error (message) ids)
      */
-    protected void handleErrorsDuringExtraction(List<Throwable> errorsList, int errorUserAction){
+    protected void handleErrorsDuringExtraction(List<Throwable> errorsList, UserAction errorUserAction){
         String errorString = "<error id>";
         switch (errorUserAction) {
-            case ErrorActivity.REQUESTED_STREAM:
+            case REQUESTED_STREAM:
-                errorString=  ErrorActivity.REQUESTED_STREAM_STRING;
+                errorString=  errorUserAction.getMessage();
                 break;
-            case ErrorActivity.REQUESTED_CHANNEL:
+            case REQUESTED_CHANNEL:
-                errorString=  ErrorActivity.REQUESTED_CHANNEL_STRING;
+                errorString=  errorUserAction.getMessage();
                 break;
         }
 

app/src/main/java/org/schabi/newpipe/workers/SearchWorker.java

@@ -13,10 +13,13 @@ import org.schabi.newpipe.extractor.exceptions.ReCaptchaException;
 import org.schabi.newpipe.extractor.search.SearchEngine;
 import org.schabi.newpipe.extractor.search.SearchResult;
 import org.schabi.newpipe.report.ErrorActivity;
+import org.schabi.newpipe.report.UserAction;
 
 import java.io.IOException;
 import java.util.EnumSet;
 
+import static org.schabi.newpipe.report.UserAction.*;
+
 /**
  * Return list of results based on a query
  *
@@ -106,7 +109,7 @@ public class SearchWorker extends AbstractWorker {
             });
         } else if (exception instanceof ExtractionException) {
             View rootView = getContext() instanceof Activity ? ((Activity) getContext()).findViewById(android.R.id.content) : null;
-            ErrorActivity.reportError(getHandler(), getContext(), exception, null, rootView, ErrorActivity.ErrorInfo.make(ErrorActivity.SEARCHED, getServiceName(), query, R.string.parsing_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, null, rootView, ErrorActivity.ErrorInfo.make(SEARCHED, getServiceName(), query, R.string.parsing_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {
@@ -115,7 +118,7 @@ public class SearchWorker extends AbstractWorker {
             });
         } else {
             View rootView = getContext() instanceof Activity ? ((Activity) getContext()).findViewById(android.R.id.content) : null;
-            ErrorActivity.reportError(getHandler(), getContext(), exception, null, rootView, ErrorActivity.ErrorInfo.make(ErrorActivity.SEARCHED, getServiceName(), query, R.string.general_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, null, rootView, ErrorActivity.ErrorInfo.make(SEARCHED, getServiceName(), query, R.string.general_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {

app/src/main/java/org/schabi/newpipe/workers/StreamExtractorWorker.java

@@ -10,9 +10,12 @@ import org.schabi.newpipe.extractor.services.youtube.YoutubeStreamExtractor;
 import org.schabi.newpipe.extractor.stream_info.StreamExtractor;
 import org.schabi.newpipe.extractor.stream_info.StreamInfo;
 import org.schabi.newpipe.report.ErrorActivity;
+import org.schabi.newpipe.report.UserAction;
 
 import java.io.IOException;
 
+import static org.schabi.newpipe.report.UserAction.*;
+
 /**
  * Extract {@link StreamInfo} with {@link StreamExtractor} from the given url of the given service
  *
@@ -66,7 +69,7 @@ public class StreamExtractorWorker extends ExtractorWorker {
         StreamExtractor streamExtractor = getService().getExtractorInstance(url);
         streamInfo = StreamInfo.getVideoInfo(streamExtractor);
 
-        if (streamInfo != null && !streamInfo.errors.isEmpty()) handleErrorsDuringExtraction(streamInfo.errors, ErrorActivity.REQUESTED_STREAM);
+        if (streamInfo != null && !streamInfo.errors.isEmpty()) handleErrorsDuringExtraction(streamInfo.errors, REQUESTED_STREAM);
 
         if (callback != null && getHandler() != null && streamInfo != null && !isInterrupted()) getHandler().post(new Runnable() {
             @Override
@@ -121,7 +124,7 @@ public class StreamExtractorWorker extends ExtractorWorker {
             });
         } else if (exception instanceof YoutubeStreamExtractor.DecryptException) {
             // custom service related exceptions
-            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(ErrorActivity.REQUESTED_STREAM, getServiceName(), url, R.string.youtube_signature_decryption_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(REQUESTED_STREAM, getServiceName(), url, R.string.youtube_signature_decryption_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {
@@ -131,9 +134,9 @@ public class StreamExtractorWorker extends ExtractorWorker {
         } else if (exception instanceof StreamInfo.StreamExctractException) {
             if (!streamInfo.errors.isEmpty()) {
                 // !!! if this case ever kicks in someone gets kicked out !!!
-                ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(ErrorActivity.REQUESTED_STREAM, getServiceName(), url, R.string.could_not_get_stream));
+                ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(REQUESTED_STREAM, getServiceName(), url, R.string.could_not_get_stream));
             } else {
-                ErrorActivity.reportError(getHandler(), getContext(), streamInfo.errors, MainActivity.class, null, ErrorActivity.ErrorInfo.make(ErrorActivity.REQUESTED_STREAM, getServiceName(), url, R.string.could_not_get_stream));
+                ErrorActivity.reportError(getHandler(), getContext(), streamInfo.errors, MainActivity.class, null, ErrorActivity.ErrorInfo.make(REQUESTED_STREAM, getServiceName(), url, R.string.could_not_get_stream));
             }
 
             getHandler().post(new Runnable() {
@@ -143,7 +146,7 @@ public class StreamExtractorWorker extends ExtractorWorker {
                 }
             });
         } else if (exception instanceof ParsingException) {
-            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(ErrorActivity.REQUESTED_STREAM, getServiceName(), url, R.string.parsing_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(REQUESTED_STREAM, getServiceName(), url, R.string.parsing_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {
@@ -151,7 +154,7 @@ public class StreamExtractorWorker extends ExtractorWorker {
                 }
             });
         } else {
-            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(ErrorActivity.REQUESTED_STREAM, getServiceName(), url, R.string.general_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, MainActivity.class, null, ErrorActivity.ErrorInfo.make(REQUESTED_STREAM, getServiceName(), url, R.string.general_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {

app/src/main/java/org/schabi/newpipe/workers/SuggestionWorker.java

@@ -11,10 +11,13 @@ import org.schabi.newpipe.R;
 import org.schabi.newpipe.extractor.SuggestionExtractor;
 import org.schabi.newpipe.extractor.exceptions.ExtractionException;
 import org.schabi.newpipe.report.ErrorActivity;
+import org.schabi.newpipe.report.UserAction;
 
 import java.io.IOException;
 import java.util.List;
 
+import static org.schabi.newpipe.report.UserAction.*;
+
 /**
  * Worker that get suggestions based on the query
  *
@@ -79,7 +82,7 @@ public class SuggestionWorker extends AbstractWorker {
 
         if (exception instanceof ExtractionException) {
             View rootView = getContext() instanceof Activity ? ((Activity) getContext()).findViewById(android.R.id.content) : null;
-            ErrorActivity.reportError(getHandler(), getContext(), exception, null, rootView, ErrorActivity.ErrorInfo.make(ErrorActivity.GET_SUGGESTIONS, getServiceName(), query, R.string.parsing_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, null, rootView, ErrorActivity.ErrorInfo.make(GET_SUGGESTIONS, getServiceName(), query, R.string.parsing_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {
@@ -95,7 +98,7 @@ public class SuggestionWorker extends AbstractWorker {
             });
         } else {
             View rootView = getContext() instanceof Activity ? ((Activity) getContext()).findViewById(android.R.id.content) : null;
-            ErrorActivity.reportError(getHandler(), getContext(), exception, null, rootView, ErrorActivity.ErrorInfo.make(ErrorActivity.GET_SUGGESTIONS, getServiceName(), query, R.string.general_error));
+            ErrorActivity.reportError(getHandler(), getContext(), exception, null, rootView, ErrorActivity.ErrorInfo.make(GET_SUGGESTIONS, getServiceName(), query, R.string.general_error));
             getHandler().post(new Runnable() {
                 @Override
                 public void run() {

app/src/main/java/us/shandian/giga/get/DownloadDataSource.java

@@ -9,12 +9,14 @@ public interface DownloadDataSource {
 
     /**
      * Load all missions
+     *
      * @return a list of download missions
      */
     List<DownloadMission> loadMissions();
 
     /**
-     * Add a downlaod mission to the storage
+     * Add a download mission to the storage
+     *
      * @param downloadMission the download mission to add
      * @return the identifier of the mission
      */
@@ -22,6 +24,7 @@ public interface DownloadDataSource {
 
     /**
      * Update a download mission which exists in the storage
+     *
      * @param downloadMission the download mission to update
      * @throws IllegalArgumentException if the mission was not added to storage
      */
@@ -30,6 +33,7 @@ public interface DownloadDataSource {
 
     /**
      * Delete a download mission
+     *
      * @param downloadMission the mission to delete
      */
     void deleteMission(DownloadMission downloadMission);

app/src/main/java/us/shandian/giga/get/DownloadManager.java

@@ -1,11 +1,11 @@
 package us.shandian.giga.get;
 
-public interface DownloadManager
+public interface DownloadManager {
-{
     int BLOCK_SIZE = 512 * 1024;
 
     /**
      * Start a new download mission
+     *
      * @param url      the url to download
      * @param location the location
      * @param name     the name of the file to create
@@ -16,24 +16,28 @@ public interface DownloadManager
 
     /**
      * Resume the execution of a download mission.
+     *
      * @param id the identifier of the mission to resume.
      */
     void resumeMission(int id);
 
     /**
      * Pause the execution of a download mission.
+     *
      * @param id the identifier of the mission to pause.
      */
     void pauseMission(int id);
 
     /**
      * Deletes the mission from the downloaded list but keeps the downloaded file.
+     *
      * @param id The mission identifier
      */
     void deleteMission(int id);
 
     /**
      * Get the download mission by its identifier
+     *
      * @param id the identifier of the download mission
      * @return the download mission or null if the mission doesn't exist
      */
@@ -41,6 +45,7 @@ public interface DownloadManager
 
     /**
      * Get the number of download missions.
+     *
      * @return the number of download missions.
      */
     int getCount();

app/src/main/java/us/shandian/giga/get/DownloadManagerImpl.java

@@ -18,10 +18,10 @@ import java.util.Comparator;
 import java.util.List;
 
 import us.shandian.giga.util.Utility;
+
 import static org.schabi.newpipe.BuildConfig.DEBUG;
 
-public class DownloadManagerImpl implements DownloadManager
+public class DownloadManagerImpl implements DownloadManager {
-{
     private static final String TAG = DownloadManagerImpl.class.getSimpleName();
     private final DownloadDataSource mDownloadDataSource;
 
@@ -29,6 +29,7 @@ public class DownloadManagerImpl implements DownloadManager
 
     /**
      * Create a new instance
+     *
      * @param searchLocations    the directories to search for unfinished downloads
      * @param downloadDataSource the data source for finished downloads
      */
@@ -40,18 +41,18 @@ public class DownloadManagerImpl implements DownloadManager
     @Override
     public int startMission(String url, String location, String name, boolean isAudio, int threads) {
         DownloadMission existingMission = getMissionByLocation(location, name);
-		if(existingMission != null) {
+        if (existingMission != null) {
             // Already downloaded or downloading
-			if(existingMission.finished) {
+            if (existingMission.finished) {
                 // Overwrite mission
                 deleteMission(mMissions.indexOf(existingMission));
             } else {
                 // Rename file (?)
                 try {
                     name = generateUniqueName(location, name);
-                }catch (Exception e) {
+                } catch (Exception e) {
                     Log.e(TAG, "Unable to generate unique name", e);
-                    name = System.currentTimeMillis() + name ;
+                    name = System.currentTimeMillis() + name;
                     Log.i(TAG, "Using " + name);
                 }
             }
@@ -84,7 +85,7 @@ public class DownloadManagerImpl implements DownloadManager
     @Override
     public void deleteMission(int i) {
         DownloadMission mission = getMission(i);
-		if(mission.finished) {
+        if (mission.finished) {
             mDownloadDataSource.deleteMission(mission);
         }
         mission.delete();
@@ -94,7 +95,7 @@ public class DownloadManagerImpl implements DownloadManager
     private void loadMissions(Iterable<String> searchLocations) {
         mMissions.clear();
         loadFinishedMissions();
-		for(String location: searchLocations) {
+        for (String location : searchLocations) {
             loadMissions(location);
         }
 
@@ -106,7 +107,7 @@ public class DownloadManagerImpl implements DownloadManager
      */
     private void loadFinishedMissions() {
         List<DownloadMission> finishedMissions = mDownloadDataSource.loadMissions();
-        if(finishedMissions == null) {
+        if (finishedMissions == null) {
             finishedMissions = new ArrayList<>();
         }
         // Ensure its sorted
@@ -117,10 +118,10 @@ public class DownloadManagerImpl implements DownloadManager
             }
         });
         mMissions.ensureCapacity(mMissions.size() + finishedMissions.size());
-		for(DownloadMission mission: finishedMissions) {
+        for (DownloadMission mission : finishedMissions) {
             File downloadedFile = mission.getDownloadedFile();
-			if(!downloadedFile.isFile()) {
+            if (!downloadedFile.isFile()) {
-				if(DEBUG) {
+                if (DEBUG) {
                     Log.d(TAG, "downloaded file removed: " + downloadedFile.getAbsolutePath());
                 }
                 mDownloadDataSource.deleteMission(mission);
@@ -140,7 +141,7 @@ public class DownloadManagerImpl implements DownloadManager
         if (f.exists() && f.isDirectory()) {
             File[] subs = f.listFiles();
 
-            if(subs == null) {
+            if (subs == null) {
                 Log.e(TAG, "listFiles() returned null");
                 return;
             }
@@ -158,7 +159,7 @@ public class DownloadManagerImpl implements DownloadManager
                         DownloadMission mis = new Gson().fromJson(str, DownloadMission.class);
 
                         if (mis.finished) {
-							if(!sub.delete()) {
+                            if (!sub.delete()) {
                                 Log.w(TAG, "Unable to delete .giga file: " + sub.getPath());
                             }
                             continue;
@@ -205,13 +206,16 @@ public class DownloadManagerImpl implements DownloadManager
 
     /**
      * Get a mission by its location and name
+     *
      * @param location the location
      * @param name     the name
      * @return the mission or null if no such mission exists
      */
-	private @Nullable DownloadMission getMissionByLocation(String location, String name) {
+    private
-		for(DownloadMission mission: mMissions) {
+    @Nullable
-			if(location.equals(mission.location) && name.equals(mission.name)) {
+    DownloadMission getMissionByLocation(String location, String name) {
+        for (DownloadMission mission : mMissions) {
+            if (location.equals(mission.location) && name.equals(mission.name)) {
                 return mission;
             }
         }
@@ -220,7 +224,7 @@ public class DownloadManagerImpl implements DownloadManager
 
     /**
      * Splits the filename into name and extension
-	 *
+     * <p>
      * Dots are ignored if they appear: not at all, at the beginning of the file,
      * at the end of the file
      *
@@ -229,7 +233,7 @@ public class DownloadManagerImpl implements DownloadManager
      */
     private static String[] splitName(String name) {
         int dotIndex = name.lastIndexOf('.');
-		if(dotIndex <= 0 || (dotIndex  == name.length() - 1)) {
+        if (dotIndex <= 0 || (dotIndex == name.length() - 1)) {
             return new String[]{name, ""};
         } else {
             return new String[]{name.substring(0, dotIndex), name.substring(dotIndex + 1)};
@@ -238,8 +242,9 @@ public class DownloadManagerImpl implements DownloadManager
 
     /**
      * Generates a unique file name.
-	 *
+     * <p>
      * e.g. "myname (1).txt" if the name "myname.txt" exists.
+     *
      * @param location the location (to check for existing files)
      * @param name     the name of the file
      * @return the unique file name
@@ -247,10 +252,10 @@ public class DownloadManagerImpl implements DownloadManager
      * @throws SecurityException        if the location is not readable
      */
     private static String generateUniqueName(String location, String name) {
-		if(location == null) throw new NullPointerException("location is null");
+        if (location == null) throw new NullPointerException("location is null");
-		if(name == null) throw new NullPointerException("name is null");
+        if (name == null) throw new NullPointerException("name is null");
         File destination = new File(location);
-		if(!destination.isDirectory()) {
+        if (!destination.isDirectory()) {
             throw new IllegalArgumentException("location is not a directory: " + location);
         }
         final String[] nameParts = splitName(name);
@@ -266,7 +271,7 @@ public class DownloadManagerImpl implements DownloadManager
         do {
             newName = nameParts[0] + " (" + downloadIndex + ")." + nameParts[1];
             ++downloadIndex;
-			if(downloadIndex == 1000) {  // Probably an error on our side
+            if (downloadIndex == 1000) {  // Probably an error on our side
                 throw new RuntimeException("Too many existing files");
             }
         } while (Arrays.binarySearch(existingName, newName) >= 0);
@@ -346,7 +351,7 @@ public class DownloadManagerImpl implements DownloadManager
         private final DownloadMission mMission;
 
         private MissionListener(DownloadMission mission) {
-			if(mission == null) throw new NullPointerException("mission is null");
+            if (mission == null) throw new NullPointerException("mission is null");
             // Could the mission be passed in onFinish()?
             mMission = mission;
         }

app/src/main/java/us/shandian/giga/get/DownloadMission.java

@@ -18,15 +18,16 @@ import us.shandian.giga.util.Utility;
 
 import static org.schabi.newpipe.BuildConfig.DEBUG;
 
-public class DownloadMission
+public class DownloadMission {
-{
     private static final String TAG = DownloadMission.class.getSimpleName();
 
     public interface MissionListener {
         HashMap<MissionListener, Handler> handlerStore = new HashMap<>();
 
         void onProgressUpdate(DownloadMission downloadMission, long done, long total);
+
         void onFinish(DownloadMission downloadMission);
+
         void onError(DownloadMission downloadMission, int errCode);
     }
 
@@ -84,12 +85,12 @@ public class DownloadMission
     }
 
     public DownloadMission(String name, String url, String location) {
-		if(name == null) throw new NullPointerException("name is null");
+        if (name == null) throw new NullPointerException("name is null");
-		if(name.isEmpty()) throw new IllegalArgumentException("name is empty");
+        if (name.isEmpty()) throw new IllegalArgumentException("name is empty");
-		if(url == null) throw new NullPointerException("url is null");
+        if (url == null) throw new NullPointerException("url is null");
-		if(url.isEmpty()) throw new IllegalArgumentException("url is empty");
+        if (url.isEmpty()) throw new IllegalArgumentException("url is empty");
-		if(location == null) throw new NullPointerException("location is null");
+        if (location == null) throw new NullPointerException("location is null");
-		if(location.isEmpty()) throw new IllegalArgumentException("location is empty");
+        if (location.isEmpty()) throw new IllegalArgumentException("location is empty");
         this.url = url;
         this.name = name;
         this.location = location;
@@ -97,13 +98,14 @@ public class DownloadMission
 
 
     private void checkBlock(long block) {
-		if(block < 0 || block >= blocks) {
+        if (block < 0 || block >= blocks) {
             throw new IllegalArgumentException("illegal block identifier");
         }
     }
 
     /**
      * Check if a block is reserved
+     *
      * @param block the block identifier
      * @return true if the block is reserved and false if otherwise
      */
@@ -121,6 +123,7 @@ public class DownloadMission
 
     /**
      * Set the download position of the file
+     *
      * @param threadId the identifier of the thread
      * @param position the download position of the thread
      */
@@ -130,6 +133,7 @@ public class DownloadMission
 
     /**
      * Get the position of a thread
+     *
      * @param threadId the identifier of the thread
      * @return the position for the thread
      */
@@ -154,7 +158,7 @@ public class DownloadMission
             writeThisToFile();
         }
 
-		for (WeakReference<MissionListener> ref: mListeners) {
+        for (WeakReference<MissionListener> ref : mListeners) {
             final MissionListener listener = ref.get();
             if (listener != null) {
                 MissionListener.handlerStore.get(listener).post(new Runnable() {
@@ -234,8 +238,7 @@ public class DownloadMission
         for (Iterator<WeakReference<MissionListener>> iterator = mListeners.iterator();
              iterator.hasNext(); ) {
             WeakReference<MissionListener> weakRef = iterator.next();
-			if (listener!=null && listener == weakRef.get())
+            if (listener != null && listener == weakRef.get()) {
-			{
                 iterator.remove();
             }
         }
@@ -315,6 +318,7 @@ public class DownloadMission
 
     /**
      * Get the path of the meta file
+     *
      * @return the path to the meta file
      */
     private String getMetaFilename() {

app/src/main/java/us/shandian/giga/get/DownloadRunnable.java

@@ -13,15 +13,14 @@ import static org.schabi.newpipe.BuildConfig.DEBUG;
  * Runnable to download blocks of a file until the file is completely downloaded,
  * an error occurs or the process is stopped.
  */
-public class DownloadRunnable implements Runnable
+public class DownloadRunnable implements Runnable {
-{
     private static final String TAG = DownloadRunnable.class.getSimpleName();
 
     private final DownloadMission mMission;
     private final int mId;
 
     public DownloadRunnable(DownloadMission mission, int id) {
-		if(mission == null) throw new NullPointerException("mission is null");
+        if (mission == null) throw new NullPointerException("mission is null");
         mMission = mission;
         mId = id;
     }

app/src/main/java/us/shandian/giga/get/DownloadRunnableFallback.java

@@ -6,13 +6,12 @@ import java.net.HttpURLConnection;
 import java.net.URL;
 
 // Single-threaded fallback mode
-public class DownloadRunnableFallback implements Runnable
+public class DownloadRunnableFallback implements Runnable {
-{
     private final DownloadMission mMission;
     //private int mId;
 
     public DownloadRunnableFallback(DownloadMission mission) {
-		if(mission == null) throw new NullPointerException("mission is null");
+        if (mission == null) throw new NullPointerException("mission is null");
         //mId = id;
         mMission = mission;
     }

app/src/main/java/us/shandian/giga/get/sqlite/DownloadMissionSQLiteHelper.java

@@ -64,6 +64,7 @@ public class DownloadMissionSQLiteHelper extends SQLiteOpenHelper {
 
     /**
      * Returns all values of the download mission as ContentValues.
+     *
      * @param downloadMission the download mission
      * @return the content values
      */
@@ -88,7 +89,7 @@ public class DownloadMissionSQLiteHelper extends SQLiteOpenHelper {
     }
 
     public static DownloadMission getMissionFromCursor(Cursor cursor) {
-        if(cursor == null) throw new NullPointerException("cursor is null");
+        if (cursor == null) throw new NullPointerException("cursor is null");
         int pos;
         String name = cursor.getString(cursor.getColumnIndexOrThrow(KEY_NAME));
         String location = cursor.getString(cursor.getColumnIndexOrThrow(KEY_LOCATION));

app/src/main/java/us/shandian/giga/get/sqlite/SQLiteDownloadDataSource.java

@@ -37,7 +37,7 @@ public class SQLiteDownloadDataSource implements DownloadDataSource {
                 null, null, null, DownloadMissionSQLiteHelper.KEY_TIMESTAMP);
 
         int count = cursor.getCount();
-        if(count == 0) return new ArrayList<>();
+        if (count == 0) return new ArrayList<>();
         result = new ArrayList<>(count);
         while (cursor.moveToNext()) {
             result.add(DownloadMissionSQLiteHelper.getMissionFromCursor(cursor));
@@ -47,7 +47,7 @@ public class SQLiteDownloadDataSource implements DownloadDataSource {
 
     @Override
     public void addMission(DownloadMission downloadMission) {
-        if(downloadMission == null) throw new NullPointerException("downloadMission is null");
+        if (downloadMission == null) throw new NullPointerException("downloadMission is null");
         SQLiteDatabase database = downloadMissionSQLiteHelper.getWritableDatabase();
         ContentValues values = DownloadMissionSQLiteHelper.getValuesOfMission(downloadMission);
         database.insert(MISSIONS_TABLE_NAME, null, values);
@@ -55,21 +55,21 @@ public class SQLiteDownloadDataSource implements DownloadDataSource {
 
     @Override
     public void updateMission(DownloadMission downloadMission) {
-        if(downloadMission == null) throw new NullPointerException("downloadMission is null");
+        if (downloadMission == null) throw new NullPointerException("downloadMission is null");
         SQLiteDatabase database = downloadMissionSQLiteHelper.getWritableDatabase();
         ContentValues values = DownloadMissionSQLiteHelper.getValuesOfMission(downloadMission);
-        String whereClause = KEY_LOCATION+ " = ? AND " +
+        String whereClause = KEY_LOCATION + " = ? AND " +
                 KEY_NAME + " = ?";
         int rowsAffected = database.update(MISSIONS_TABLE_NAME, values,
                 whereClause, new String[]{downloadMission.location, downloadMission.name});
-        if(rowsAffected != 1) {
+        if (rowsAffected != 1) {
             Log.e(TAG, "Expected 1 row to be affected by update but got " + rowsAffected);
         }
     }
 
     @Override
     public void deleteMission(DownloadMission downloadMission) {
-        if(downloadMission == null) throw new NullPointerException("downloadMission is null");
+        if (downloadMission == null) throw new NullPointerException("downloadMission is null");
         SQLiteDatabase database = downloadMissionSQLiteHelper.getWritableDatabase();
         database.delete(MISSIONS_TABLE_NAME,
                 KEY_LOCATION + " = ? AND " +

app/src/main/java/us/shandian/giga/service/DownloadManagerService.java

@@ -6,7 +6,6 @@ import android.app.PendingIntent;
 import android.app.Service;
 import android.content.Context;
 import android.content.Intent;
-import android.content.ServiceConnection;
 import android.graphics.drawable.BitmapDrawable;
 import android.graphics.drawable.Drawable;
 import android.net.Uri;
@@ -16,6 +15,7 @@ import android.os.HandlerThread;
 import android.os.IBinder;
 import android.os.Message;
 import android.support.v4.app.NotificationCompat.Builder;
+import android.support.v4.content.ContextCompat;
 import android.support.v4.content.PermissionChecker;
 import android.util.Log;
 import android.widget.Toast;
@@ -34,8 +34,7 @@ import us.shandian.giga.get.sqlite.SQLiteDownloadDataSource;
 
 import static org.schabi.newpipe.BuildConfig.DEBUG;
 
-public class DownloadManagerService extends Service
+public class DownloadManagerService extends Service {
-{
 
     private static final String TAG = DownloadManagerService.class.getSimpleName();
 
@@ -58,7 +57,6 @@ public class DownloadManagerService extends Service
     private DownloadDataSource mDataSource;
 
 
-
     private MissionListener missionListener = new MissionListener();
 
 
@@ -77,7 +75,7 @@ public class DownloadManagerService extends Service
         }
 
         mBinder = new DMBinder();
-		if(mDataSource == null) {
+        if (mDataSource == null) {
             mDataSource = new SQLiteDownloadDataSource(this);
         }
         if (mManager == null) {
@@ -95,7 +93,7 @@ public class DownloadManagerService extends Service
         i.setAction(Intent.ACTION_MAIN);
         i.setClass(this, DownloadActivity.class);
 
-		Drawable icon = this.getResources().getDrawable(R.mipmap.ic_launcher);
+        Drawable icon = ContextCompat.getDrawable(this, R.mipmap.ic_launcher);
 
         Builder builder = new Builder(this)
                 .setContentIntent(PendingIntent.getActivity(this, 0, i, 0))
@@ -159,7 +157,7 @@ public class DownloadManagerService extends Service
         }
         Log.i(TAG, "Got intent: " + intent);
         String action = intent.getAction();
-		if(action != null && action.equals(Intent.ACTION_RUN)) {
+        if (action != null && action.equals(Intent.ACTION_RUN)) {
             String name = intent.getStringExtra(EXTRA_NAME);
             String location = intent.getStringExtra(EXTRA_LOCATION);
             int threads = intent.getIntExtra(EXTRA_THREADS, 1);
@@ -190,13 +188,13 @@ public class DownloadManagerService extends Service
         int permissionCheck;
         if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.JELLY_BEAN) {
             permissionCheck = PermissionChecker.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE);
-			if(permissionCheck == PermissionChecker.PERMISSION_DENIED) {
+            if (permissionCheck == PermissionChecker.PERMISSION_DENIED) {
                 Toast.makeText(this, "Permission denied (read)", Toast.LENGTH_SHORT).show();
             }
         }
 
         permissionCheck = PermissionChecker.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE);
-		if(permissionCheck == PermissionChecker.PERMISSION_DENIED) {
+        if (permissionCheck == PermissionChecker.PERMISSION_DENIED) {
             Toast.makeText(this, "Permission denied (write)", Toast.LENGTH_SHORT).show();
         }
 
@@ -227,7 +225,7 @@ public class DownloadManagerService extends Service
     }
 
 
-	class MissionListener implements DownloadMission.MissionListener {
+    private class MissionListener implements DownloadMission.MissionListener {
         @Override
         public void onProgressUpdate(DownloadMission downloadMission, long done, long total) {
             long now = System.currentTimeMillis();

app/src/main/java/us/shandian/giga/ui/adapter/MissionAdapter.java

@@ -7,6 +7,8 @@ import android.net.Uri;
 import android.os.AsyncTask;
 import android.os.Build;
 import android.support.v4.content.FileProvider;
+import android.support.v4.view.ViewCompat;
+import android.support.v7.widget.RecyclerView;
 import android.util.Log;
 import android.view.LayoutInflater;
 import android.view.Menu;
@@ -18,14 +20,13 @@ import android.widget.ImageView;
 import android.widget.PopupMenu;
 import android.widget.TextView;
 
-import android.support.v7.widget.RecyclerView;
+import org.schabi.newpipe.R;
 
 import java.io.File;
 import java.util.HashMap;
 import java.util.Locale;
 import java.util.Map;
 
-import org.schabi.newpipe.R;
 import us.shandian.giga.get.DownloadManager;
 import us.shandian.giga.get.DownloadMission;
 import us.shandian.giga.service.DownloadManagerService;
@@ -35,8 +36,7 @@ import us.shandian.giga.util.Utility;
 import static android.content.Intent.FLAG_GRANT_PREFIX_URI_PERMISSION;
 import static android.content.Intent.FLAG_GRANT_READ_URI_PERMISSION;
 
-public class MissionAdapter extends RecyclerView.Adapter<MissionAdapter.ViewHolder>
+public class MissionAdapter extends RecyclerView.Adapter<MissionAdapter.ViewHolder> {
-{
     private static final Map<Integer, String> ALGORITHMS = new HashMap<>();
     private static final String TAG = "MissionAdapter";
 
@@ -108,7 +108,7 @@ public class MissionAdapter extends RecyclerView.Adapter<MissionAdapter.ViewHold
         h.size.setText(Utility.formatBytes(ms.length));
 
         h.progress = new ProgressDrawable(mContext, Utility.getBackgroundForFileType(type), Utility.getForegroundForFileType(type));
-		h.bkg.setBackgroundDrawable(h.progress);
+        ViewCompat.setBackground(h.bkg, h.progress);
 
         h.observer = new MissionObserver(this, h);
         ms.addListener(h.observer);
@@ -285,33 +285,6 @@ public class MissionAdapter extends RecyclerView.Adapter<MissionAdapter.ViewHold
         mContext.startActivity(intent);
     }
 
-	private class ChecksumTask extends AsyncTask<String, Void, String> {
-		ProgressDialog prog;
-
-		@Override
-		protected void onPreExecute() {
-			super.onPreExecute();
-			
-			// Create dialog
-			prog = new ProgressDialog(mContext);
-			prog.setCancelable(false);
-			prog.setMessage(mContext.getString(R.string.msg_wait));
-			prog.show();
-		}
-
-		@Override
-		protected String doInBackground(String... params) {
-			return Utility.checksum(params[0], params[1]);
-		}
-
-		@Override
-		protected void onPostExecute(String result) {
-			super.onPostExecute(result);
-			prog.dismiss();
-			Utility.copyToClipboard(mContext, result);
-		}
-	}
-	
     static class ViewHolder extends RecyclerView.ViewHolder {
         public DownloadMission mission;
         public int position;
@@ -332,12 +305,12 @@ public class MissionAdapter extends RecyclerView.Adapter<MissionAdapter.ViewHold
         public ViewHolder(View v) {
             super(v);
 
-			status = Utility.findViewById(v, R.id.item_status);
+            status = (TextView) v.findViewById(R.id.item_status);
-			icon = Utility.findViewById(v, R.id.item_icon);
+            icon = (ImageView) v.findViewById(R.id.item_icon);
-			name = Utility.findViewById(v, R.id.item_name);
+            name = (TextView) v.findViewById(R.id.item_name);
-			size = Utility.findViewById(v, R.id.item_size);
+            size = (TextView) v.findViewById(R.id.item_size);
-			bkg = Utility.findViewById(v, R.id.item_bkg);
+            bkg = v.findViewById(R.id.item_bkg);
-			menu = Utility.findViewById(v, R.id.item_more);
+            menu = (ImageView) v.findViewById(R.id.item_more);
         }
     }
 
@@ -372,4 +345,31 @@ public class MissionAdapter extends RecyclerView.Adapter<MissionAdapter.ViewHold
         }
 
     }
+
+    private class ChecksumTask extends AsyncTask<String, Void, String> {
+        ProgressDialog prog;
+
+        @Override
+        protected void onPreExecute() {
+            super.onPreExecute();
+
+            // Create dialog
+            prog = new ProgressDialog(mContext);
+            prog.setCancelable(false);
+            prog.setMessage(mContext.getString(R.string.msg_wait));
+            prog.show();
+        }
+
+        @Override
+        protected String doInBackground(String... params) {
+            return Utility.checksum(params[0], params[1]);
+        }
+
+        @Override
+        protected void onPostExecute(String result) {
+            super.onPostExecute(result);
+            prog.dismiss();
+            Utility.copyToClipboard(mContext, result);
+        }
+    }
 }

app/src/main/java/us/shandian/giga/ui/common/ProgressDrawable.java

@@ -6,14 +6,16 @@ import android.graphics.ColorFilter;
 import android.graphics.Paint;
 import android.graphics.PixelFormat;
 import android.graphics.drawable.Drawable;
+import android.support.annotation.ColorRes;
+import android.support.annotation.NonNull;
+import android.support.v4.content.ContextCompat;
 
-public class ProgressDrawable extends Drawable
+public class ProgressDrawable extends Drawable {
-{
     private float mProgress;
     private int mBackgroundColor, mForegroundColor;
 
-	public ProgressDrawable(Context context, int background, int foreground) {
+    public ProgressDrawable(Context context, @ColorRes int background, @ColorRes int foreground) {
-		this(context.getResources().getColor(background), context.getResources().getColor(foreground));
+        this(ContextCompat.getColor(context, background), ContextCompat.getColor(context, foreground));
     }
 
     public ProgressDrawable(int background, int foreground) {
@@ -27,7 +29,7 @@ public class ProgressDrawable extends Drawable
     }
 
     @Override
-	public void draw(Canvas canvas) {
+    public void draw(@NonNull Canvas canvas) {
         int width = canvas.getWidth();
         int height = canvas.getHeight();
 

app/src/main/java/us/shandian/giga/ui/common/ToolbarActivity.java

@@ -1,15 +1,12 @@
 package us.shandian.giga.ui.common;
 
 import android.os.Bundle;
-
 import android.support.v7.app.ActionBarActivity;
 import android.support.v7.widget.Toolbar;
 
 import org.schabi.newpipe.R;
-import us.shandian.giga.util.Utility;
 
-public abstract class ToolbarActivity extends ActionBarActivity
+public abstract class ToolbarActivity extends ActionBarActivity {
-{
     protected Toolbar mToolbar;
 
     @Override
@@ -17,7 +14,7 @@ public abstract class ToolbarActivity extends ActionBarActivity
         super.onCreate(savedInstanceState);
         setContentView(getLayoutResource());
 
-		mToolbar = Utility.findViewById(this, R.id.toolbar);
+        mToolbar = (Toolbar) this.findViewById(R.id.toolbar);
 
         setSupportActionBar(mToolbar);
     }

app/src/main/java/us/shandian/giga/ui/fragment/AllMissionsFragment.java

@@ -3,8 +3,7 @@ package us.shandian.giga.ui.fragment;
 import us.shandian.giga.get.DownloadManager;
 import us.shandian.giga.service.DownloadManagerService;
 
-public class AllMissionsFragment extends MissionsFragment
+public class AllMissionsFragment extends MissionsFragment {
-{
 
     @Override
     protected DownloadManager setupDownloadManager(DownloadManagerService.DMBinder binder) {

app/src/main/java/us/shandian/giga/ui/fragment/MissionsFragment.java

@@ -23,10 +23,8 @@ import org.schabi.newpipe.R;
 import us.shandian.giga.get.DownloadManager;
 import us.shandian.giga.service.DownloadManagerService;
 import us.shandian.giga.ui.adapter.MissionAdapter;
-import us.shandian.giga.util.Utility;
 
-public abstract class MissionsFragment extends Fragment
+public abstract class MissionsFragment extends Fragment {
-{
     private DownloadManager mManager;
     private DownloadManagerService.DMBinder mBinder;
 
@@ -70,7 +68,7 @@ public abstract class MissionsFragment extends Fragment
         getActivity().bindService(i, mConnection, Context.BIND_AUTO_CREATE);
 
         // Views
-		mList = Utility.findViewById(v, R.id.mission_recycler);
+        mList = (RecyclerView) v.findViewById(R.id.mission_recycler);
 
         // Init
         mGridManager = new GridLayoutManager(getActivity(), 2);
@@ -82,7 +80,9 @@ public abstract class MissionsFragment extends Fragment
         return v;
     }
 
-	/** Added in API level 23. */
+    /**
+     * Added in API level 23.
+     */
     @Override
     public void onAttach(Context activity) {
         super.onAttach(activity);
@@ -93,8 +93,10 @@ public abstract class MissionsFragment extends Fragment
         mActivity = activity;
     }
 
-	/** deprecated in API level 23,
+    /**
-	 * but must remain to allow compatibility with api<23 */
+     * deprecated in API level 23,
+     * but must remain to allow compatibility with api<23
+     */
     @Override
     public void onAttach(Activity activity) {
         super.onAttach(activity);

app/src/main/java/us/shandian/giga/util/CrashHandler.java

@@ -9,8 +9,7 @@ import java.io.File;
 import java.io.PrintWriter;
 
 //todo: replace this by using the internal crash handler of newpipe
-public class CrashHandler implements Thread.UncaughtExceptionHandler
+public class CrashHandler implements Thread.UncaughtExceptionHandler {
-{
     public static final String CRASH_DIR = Environment.getExternalStorageDirectory().getPath() + "/GigaCrash/";
     public static final String CRASH_LOG = CRASH_DIR + "last_crash.log";
     public static final String CRASH_TAG = CRASH_DIR + ".crashed";

app/src/main/java/us/shandian/giga/util/Utility.java

@@ -1,32 +1,27 @@
 package us.shandian.giga.util;
 
-import android.app.Activity;
-import android.content.ClipboardManager;
 import android.content.ClipData;
+import android.content.ClipboardManager;
 import android.content.Context;
-import android.content.Intent;
+import android.support.annotation.ColorRes;
-import android.view.View;
+import android.support.annotation.DrawableRes;
+import android.support.annotation.Nullable;
 import android.widget.Toast;
 
+import org.schabi.newpipe.R;
+
 import java.io.BufferedInputStream;
 import java.io.File;
 import java.io.FileInputStream;
-import java.io.FileOutputStream;
 import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 
-import org.schabi.newpipe.settings.NewPipeSettings;
+public class Utility {
-import org.schabi.newpipe.R;
 
-import com.nononsenseapps.filepicker.FilePickerActivity;
+    public enum FileType {
-import com.nononsenseapps.filepicker.AbstractFilePickerFragment;
-
-public class Utility
-{
-	
-	public static enum FileType {
         VIDEO,
         MUSIC,
         UNKNOWN
@@ -109,30 +104,25 @@ public class Utility
         }
     }
 
-	public static <T> T findViewById(View v, int id) {
+    @Nullable
-		return (T) v.findViewById(id);
-	}
-	
-	public static <T> T findViewById(Activity activity, int id) {
-		return (T) activity.findViewById(id);
-	}
-	
     public static String getFileExt(String url) {
-		if (url.indexOf("?")>-1) {
+        int index;
-			url = url.substring(0,url.indexOf("?"));
+        if ((index = url.indexOf("?")) > -1) {
+            url = url.substring(0, index);
         }
-		if (url.lastIndexOf(".") == -1) {
+
+        index = url.lastIndexOf(".");
+        if (index == -1) {
             return null;
         } else {
-			String ext = url.substring(url.lastIndexOf(".") );
+            String ext = url.substring(index);
-			if (ext.indexOf("%")>-1) {
+            if ((index = ext.indexOf("%")) > -1) {
-				ext = ext.substring(0,ext.indexOf("%"));
+                ext = ext.substring(0, index);
             }
-			if (ext.indexOf("/")>-1) {
+            if ((index = ext.indexOf("/")) > -1) {
-				ext = ext.substring(0,ext.indexOf("/"));
+                ext = ext.substring(0, index);
             }
             return ext.toLowerCase();
-
         }
     }
 
@@ -147,16 +137,7 @@ public class Utility
         }
     }
 
-	public static Boolean isMusicFile(String file)
+    @ColorRes
-	{
-		 return Utility.getFileType(file) == FileType.MUSIC;
-	}
-
-	public static Boolean isVideoFile(String file)
-	{
-		return Utility.getFileType(file) == FileType.VIDEO;
-	}
-	
     public static int getBackgroundForFileType(FileType type) {
         switch (type) {
             case MUSIC:
@@ -168,6 +149,7 @@ public class Utility
         }
     }
 
+    @ColorRes
     public static int getForegroundForFileType(FileType type) {
         switch (type) {
             case MUSIC:
@@ -179,8 +161,9 @@ public class Utility
         }
     }
 
+    @DrawableRes
     public static int getIconForFileType(FileType type) {
-		switch(type) {
+        switch (type) {
             case MUSIC:
                 return R.drawable.music;
             case VIDEO:
@@ -190,24 +173,6 @@ public class Utility
         }
     }
 
-	public static boolean isDirectoryAvailble(String path) {
-		File dir = new File(path);
-		return dir.exists() && dir.isDirectory();
-	}
-
-	public static boolean isDownloadDirectoryAvailble(Context context) {
-		return isDirectoryAvailble(NewPipeSettings.getVideoDownloadPath(context));
-	}
-
-	public static void showDirectoryChooser(Activity activity) {
-		Intent i = new Intent(activity, FilePickerActivity.class);
-		i.setAction(Intent.ACTION_GET_CONTENT);
-		i.putExtra(FilePickerActivity.EXTRA_ALLOW_MULTIPLE, false);
-		i.putExtra(FilePickerActivity.EXTRA_ALLOW_CREATE_DIR, true);
-		i.putExtra(FilePickerActivity.EXTRA_MODE, AbstractFilePickerFragment.MODE_DIR);
-		activity.startActivityForResult(i, 233);
-	}
-	
     public static void copyToClipboard(Context context, String str) {
         ClipboardManager cm = (ClipboardManager) context.getSystemService(Context.CLIPBOARD_SERVICE);
         cm.setPrimaryClip(ClipData.newPlainText("text", str));

app/src/test/java/org/schabi/newpipe/report/ErrorActivityTest.java

@@ -0,0 +1,38 @@
+package org.schabi.newpipe.report;
+
+import android.app.Activity;
+
+import org.junit.Test;
+import org.schabi.newpipe.MainActivity;
+import org.schabi.newpipe.RouterActivity;
+import org.schabi.newpipe.fragments.detail.VideoDetailFragment;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNull;
+
+/**
+ * Unit tests for {@link ErrorActivity}
+ */
+public class ErrorActivityTest {
+    @Test
+    public void getReturnActivity() throws Exception {
+        Class<? extends Activity> returnActivity;
+        returnActivity = ErrorActivity.getReturnActivity(MainActivity.class);
+        assertEquals(MainActivity.class, returnActivity);
+
+        returnActivity = ErrorActivity.getReturnActivity(RouterActivity.class);
+        assertEquals(RouterActivity.class, returnActivity);
+
+        returnActivity = ErrorActivity.getReturnActivity(null);
+        assertNull(returnActivity);
+
+        returnActivity = ErrorActivity.getReturnActivity(Integer.class);
+        assertEquals(MainActivity.class, returnActivity);
+
+        returnActivity = ErrorActivity.getReturnActivity(VideoDetailFragment.class);
+        assertEquals(MainActivity.class, returnActivity);
+    }
+
+
+
+}

app/src/test/java/us/shandian/giga/get/get/DownloadManagerImplTest.java

@@ -31,18 +31,18 @@ import static org.mockito.Mockito.when;
 public class DownloadManagerImplTest {
 
     private DownloadManagerImpl downloadManager;
-    private DownloadDataSource dowloadDataSource;
+    private DownloadDataSource downloadDataSource;
     private ArrayList<DownloadMission> missions;
 
     @org.junit.Before
     public void setUp() throws Exception {
-        dowloadDataSource = mock(DownloadDataSource.class);
+        downloadDataSource = mock(DownloadDataSource.class);
         missions = new ArrayList<>();
         for(int i = 0; i < 50; ++i){
             missions.add(generateFinishedDownloadMission());
         }
-        when(dowloadDataSource.loadMissions()).thenReturn(new ArrayList<>(missions));
+        when(downloadDataSource.loadMissions()).thenReturn(new ArrayList<>(missions));
-        downloadManager = new DownloadManagerImpl(new ArrayList<String>(), dowloadDataSource);
+        downloadManager = new DownloadManagerImpl(new ArrayList<String>(), downloadDataSource);
     }
 
     @Test(expected = NullPointerException.class)
@@ -82,10 +82,10 @@ public class DownloadManagerImplTest {
             missions.add(mission);
         }
 
-        dowloadDataSource = mock(DownloadDataSource.class);
+        downloadDataSource = mock(DownloadDataSource.class);
-        when(dowloadDataSource.loadMissions()).thenReturn(new ArrayList<>(missions));
+        when(downloadDataSource.loadMissions()).thenReturn(new ArrayList<>(missions));
-        downloadManager = new DownloadManagerImpl(new ArrayList<String>(), dowloadDataSource);
+        downloadManager = new DownloadManagerImpl(new ArrayList<String>(), downloadDataSource);
-        verify(dowloadDataSource, times(1)).loadMissions();
+        verify(downloadDataSource, times(1)).loadMissions();
 
         assertEquals(50, downloadManager.getCount());