DeskClock: Cleanup: Add/Fix annotations

Change-Id: I0908a41a0b13a5c86d33b54cb0837cea2f7d34c7

28 files changed, 89 insertions, 45 deletions

diff --git a/src/com/android/alarmclock/DigitalAppWidgetProvider.java b/src/com/android/alarmclock/DigitalAppWidgetProvider.java
index 2c18db737..a258580c8 100644
--- a/src/com/android/alarmclock/DigitalAppWidgetProvider.java
+++ b/src/com/android/alarmclock/DigitalAppWidgetProvider.java
@@ -529,6 +529,7 @@ public class DigitalAppWidgetProvider extends AppWidgetProvider {
             return new Sizes(mTargetWidthPx, mTargetHeightPx, mLargestClockFontSizePx);
         }
 
+        @NonNull
         @Override
         public String toString() {
             final StringBuilder builder = new StringBuilder(1000);
diff --git a/src/com/android/deskclock/AlarmClockFragment.java b/src/com/android/deskclock/AlarmClockFragment.java
index 2cb611d15..efc56fb2f 100644
--- a/src/com/android/deskclock/AlarmClockFragment.java
+++ b/src/com/android/deskclock/AlarmClockFragment.java
@@ -255,7 +255,7 @@ public final class AlarmClockFragment extends DeskClockFragment implements
     }
 
     @Override
-    public void onSaveInstanceState(Bundle outState) {
+    public void onSaveInstanceState(@NonNull Bundle outState) {
         super.onSaveInstanceState(outState);
         mAlarmTimeClickHandler.saveInstance(outState);
         outState.putLong(KEY_EXPANDED_ID, mExpandedAlarmId);
@@ -272,13 +272,14 @@ public final class AlarmClockFragment extends DeskClockFragment implements
         mAlarmUpdateHandler.asyncUpdateAlarm(alarm, false, true);
     }
 
+    @NonNull
     @Override
     public Loader<Cursor> onCreateLoader(int id, Bundle args) {
         return Alarm.getAlarmsCursorLoader(getActivity());
     }
 
     @Override
-    public void onLoadFinished(Loader<Cursor> cursorLoader, Cursor data) {
+    public void onLoadFinished(@NonNull Loader<Cursor> cursorLoader, Cursor data) {
         final List<AlarmItemHolder> itemHolders = new ArrayList<>(data.getCount());
         for (data.moveToFirst(); !data.isAfterLast(); data.moveToNext()) {
             final Alarm alarm = new Alarm(data);
@@ -380,7 +381,7 @@ public final class AlarmClockFragment extends DeskClockFragment implements
     }
 
     @Override
-    public void onLoaderReset(Loader<Cursor> cursorLoader) {
+    public void onLoaderReset(@NonNull Loader<Cursor> cursorLoader) {
     }
 
     @Override
@@ -434,7 +435,7 @@ public final class AlarmClockFragment extends DeskClockFragment implements
     private final class ScrollPositionWatcher extends RecyclerView.OnScrollListener
             implements View.OnLayoutChangeListener {
         @Override
-        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+        public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
             setTabScrolledToTop(Utils.isScrolledToTop(mRecyclerView));
         }
 
diff --git a/src/com/android/deskclock/AlarmRecyclerView.java b/src/com/android/deskclock/AlarmRecyclerView.java
index 13bffcfbb..57469813d 100644
--- a/src/com/android/deskclock/AlarmRecyclerView.java
+++ b/src/com/android/deskclock/AlarmRecyclerView.java
@@ -17,6 +17,8 @@
 package com.android.deskclock;
 
 import android.content.Context;
+
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.recyclerview.widget.RecyclerView;
 import android.util.AttributeSet;
@@ -42,7 +44,7 @@ public class AlarmRecyclerView extends RecyclerView {
         super(context, attrs, defStyle);
         addOnItemTouchListener(new RecyclerView.SimpleOnItemTouchListener() {
             @Override
-            public boolean onInterceptTouchEvent(RecyclerView rv, MotionEvent e) {
+            public boolean onInterceptTouchEvent(@NonNull RecyclerView rv, @NonNull MotionEvent e) {
                 // Disable scrolling/user action to prevent choppy animations.
                 return rv.getItemAnimator().isRunning();
             }
diff --git a/src/com/android/deskclock/ClockFragment.java b/src/com/android/deskclock/ClockFragment.java
index c78e9cd50..79821ce3e 100644
--- a/src/com/android/deskclock/ClockFragment.java
+++ b/src/com/android/deskclock/ClockFragment.java
@@ -94,7 +94,7 @@ public final class ClockFragment extends DeskClockFragment {
     }
 
     @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle icicle) {
+    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle icicle) {
         super.onCreateView(inflater, container, icicle);
 
         final View fragmentView = inflater.inflate(R.layout.clock_fragment, container, false);
@@ -291,7 +291,7 @@ public final class ClockFragment extends DeskClockFragment {
     private final class ScrollPositionWatcher extends RecyclerView.OnScrollListener
             implements View.OnLayoutChangeListener {
         @Override
-        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+        public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
             setTabScrolledToTop(Utils.isScrolledToTop(mCityList));
         }
 
@@ -339,8 +339,9 @@ public final class ClockFragment extends DeskClockFragment {
             return WORLD_CLOCK;
         }
 
+        @NonNull
         @Override
-        public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+        public RecyclerView.ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
             final View view = mInflater.inflate(viewType, parent, false);
             switch (viewType) {
                 case WORLD_CLOCK:
@@ -353,7 +354,7 @@ public final class ClockFragment extends DeskClockFragment {
         }
 
         @Override
-        public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) {
+        public void onBindViewHolder(@NonNull RecyclerView.ViewHolder holder, int position) {
             final int viewType = getItemViewType(position);
             switch (viewType) {
                 case WORLD_CLOCK:
diff --git a/src/com/android/deskclock/DeskClock.java b/src/com/android/deskclock/DeskClock.java
index d5f36cff7..a5a7beae2 100644
--- a/src/com/android/deskclock/DeskClock.java
+++ b/src/com/android/deskclock/DeskClock.java
@@ -475,8 +475,8 @@ public class DeskClock extends BaseActivity
     }
 
     @Override
-    public void onRequestPermissionsResult(int requestCode, String[] permissions,
-                                           int[] grantResults) {
+    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
+                                           @NonNull int[] grantResults) {
         if (requestCode == CODE_FOR_ALARM_PERMISSION) {
             if (hasEssentialPermissions()) {
                 LogUtils.i("Essential permissions granted!");
diff --git a/src/com/android/deskclock/DropShadowController.java b/src/com/android/deskclock/DropShadowController.java
index 53edd7711..96f95a249 100644
--- a/src/com/android/deskclock/DropShadowController.java
+++ b/src/com/android/deskclock/DropShadowController.java
@@ -17,6 +17,8 @@
 package com.android.deskclock;
 
 import android.animation.ValueAnimator;
+
+import androidx.annotation.NonNull;
 import androidx.recyclerview.widget.RecyclerView;
 import android.view.View;
 import android.widget.AbsListView;
@@ -148,7 +150,7 @@ public final class DropShadowController {
 
         // RecyclerView scrolled.
         @Override
-        public void onScrolled(RecyclerView view, int dx, int dy) {
+        public void onScrolled(@NonNull RecyclerView view, int dx, int dy) {
             updateDropShadow(!Utils.isScrolledToTop(view));
         }
 
diff --git a/src/com/android/deskclock/ItemAdapter.java b/src/com/android/deskclock/ItemAdapter.java
index a41763694..ca4765343 100644
--- a/src/com/android/deskclock/ItemAdapter.java
+++ b/src/com/android/deskclock/ItemAdapter.java
@@ -200,6 +200,7 @@ public class ItemAdapter<T extends ItemAdapter.ItemHolder>
      * @param itemHolder the item holder to add
      * @return this object, allowing calls to methods in this class to be chained
      */
+    @SuppressWarnings("unused")
     public ItemAdapter addItem(int position, @NonNull T itemHolder) {
         itemHolder.addOnItemChangedListener(mItemChangedNotifier);
         position = Math.min(position, mItemHolders.size());
@@ -257,8 +258,9 @@ public class ItemAdapter<T extends ItemAdapter.ItemHolder>
         return mItemHolders.get(position).getItemViewType();
     }
 
+    @NonNull
     @Override
-    public ItemViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+    public ItemViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
         final ItemViewHolder.Factory factory = mFactoriesByViewType.get(viewType);
         if (factory != null) {
             return factory.createViewHolder(parent, viewType);
@@ -365,6 +367,7 @@ public class ItemAdapter<T extends ItemAdapter.ItemHolder>
          * Invokes {@link OnItemChangedListener#onItemChanged(ItemHolder, Object)} for all
          * listeners added via {@link #addOnItemChangedListener(OnItemChangedListener)}.
          */
+        @SuppressWarnings("unused")
         public final void notifyItemChanged(Object payload) {
             for (OnItemChangedListener listener : mOnItemChangedListeners) {
                 listener.onItemChanged(this, payload);
diff --git a/src/com/android/deskclock/ItemAnimator.java b/src/com/android/deskclock/ItemAnimator.java
index 756d4e951..0a01f147f 100644
--- a/src/com/android/deskclock/ItemAnimator.java
+++ b/src/com/android/deskclock/ItemAnimator.java
@@ -289,7 +289,7 @@ public class ItemAnimator extends SimpleItemAnimator {
     }
 
     @Override
-    public void endAnimation(ViewHolder holder) {
+    public void endAnimation(@NonNull ViewHolder holder) {
         final Animator animator = mAnimators.get(holder);
 
         mAnimators.remove(holder);
@@ -337,6 +337,7 @@ public class ItemAnimator extends SimpleItemAnimator {
         return itemHolderInfo;
     }
 
+    @NonNull
     @Override
     public ItemHolderInfo obtainHolderInfo() {
         return new PayloadItemHolderInfo();
diff --git a/src/com/android/deskclock/LabelDialogFragment.java b/src/com/android/deskclock/LabelDialogFragment.java
index d997cdb78..408d65122 100644
--- a/src/com/android/deskclock/LabelDialogFragment.java
+++ b/src/com/android/deskclock/LabelDialogFragment.java
@@ -117,6 +117,7 @@ public class LabelDialogFragment extends DialogFragment {
         }
     }
 
+    @NonNull
     @Override
     public Dialog onCreateDialog(Bundle savedInstanceState) {
         final Bundle args = getArguments() == null ? Bundle.EMPTY : getArguments();
diff --git a/src/com/android/deskclock/Utils.java b/src/com/android/deskclock/Utils.java
index 03c7fcd50..368f5e482 100644
--- a/src/com/android/deskclock/Utils.java
+++ b/src/com/android/deskclock/Utils.java
@@ -51,6 +51,7 @@ import android.widget.TextView;
 
 import androidx.annotation.AnyRes;
 import androidx.annotation.DrawableRes;
+import androidx.annotation.NonNull;
 import androidx.annotation.StringRes;
 import androidx.core.os.BuildCompat;
 import androidx.core.view.AccessibilityDelegateCompat;
@@ -552,7 +553,8 @@ public class Utils {
         }
 
         @Override
-        public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfoCompat info) {
+        public void onInitializeAccessibilityNodeInfo(@NonNull View host,
+                                                      @NonNull AccessibilityNodeInfoCompat info) {
             super.onInitializeAccessibilityNodeInfo(host, info);
             if (mIsAlwaysAccessibilityVisible) {
                 info.setVisibleToUser(true);
diff --git a/src/com/android/deskclock/alarms/TimePickerDialogFragment.java b/src/com/android/deskclock/alarms/TimePickerDialogFragment.java
index f82bea96b..7fb1e0144 100644
--- a/src/com/android/deskclock/alarms/TimePickerDialogFragment.java
+++ b/src/com/android/deskclock/alarms/TimePickerDialogFragment.java
@@ -23,6 +23,8 @@ import android.content.DialogInterface;
 import android.os.Bundle;
 import android.text.format.DateFormat;
 import android.widget.TimePicker;
+
+import androidx.annotation.NonNull;
 import androidx.appcompat.app.AlertDialog;
 import androidx.fragment.app.DialogFragment;
 import androidx.fragment.app.Fragment;
@@ -45,8 +47,8 @@ public class TimePickerDialogFragment extends DialogFragment {
     private static final String ARG_HOUR = TAG + "_hour";
     private static final String ARG_MINUTE = TAG + "_minute";
 
+    @NonNull
     @Override
-    @SuppressWarnings("deprecation")
     public Dialog onCreateDialog(Bundle savedInstanceState) {
         final OnTimeSetListener listener = ((OnTimeSetListener) getParentFragment());
 
diff --git a/src/com/android/deskclock/controller/EventController.java b/src/com/android/deskclock/controller/EventController.java
index 457756a2e..729b9180a 100644
--- a/src/com/android/deskclock/controller/EventController.java
+++ b/src/com/android/deskclock/controller/EventController.java
@@ -31,6 +31,7 @@ class EventController {
         mEventTrackers.add(eventTracker);
     }
 
+    @SuppressWarnings("unused")
     void removeEventTracker(EventTracker eventTracker) {
         mEventTrackers.remove(eventTracker);
     }
diff --git a/src/com/android/deskclock/data/City.java b/src/com/android/deskclock/data/City.java
index 7a41d087c..e45248b05 100644
--- a/src/com/android/deskclock/data/City.java
+++ b/src/com/android/deskclock/data/City.java
@@ -16,6 +16,8 @@
 
 package com.android.deskclock.data;
 
+import androidx.annotation.NonNull;
+
 import java.text.Collator;
 import java.util.Comparator;
 import java.util.Locale;
@@ -101,6 +103,7 @@ public final class City {
         return getNameUpperCaseNoSpecialCharacters().startsWith(upperCaseQueryNoSpecialCharacters);
     }
 
+    @NonNull
     @Override
     public String toString() {
         return String.format(Locale.US,
diff --git a/src/com/android/deskclock/data/DataModel.java b/src/com/android/deskclock/data/DataModel.java
index ae8f1aeb1..5cab97063 100644
--- a/src/com/android/deskclock/data/DataModel.java
+++ b/src/com/android/deskclock/data/DataModel.java
@@ -65,9 +65,7 @@ public final class DataModel {
 
     /** Indicates the reason alarms may not fire or may fire silently. */
     public enum SilentSetting {
-        @SuppressWarnings("unchecked")
         DO_NOT_DISTURB(R.string.alarms_blocked_by_dnd, 0, Predicate.FALSE, null),
-        @SuppressWarnings("unchecked")
         MUTED_VOLUME(R.string.alarm_volume_muted,
                 R.string.unmute_alarm_volume,
                 Predicate.TRUE,
@@ -76,7 +74,6 @@ public final class DataModel {
                 R.string.change_setting_action,
                 new ChangeSoundActionPredicate(),
                 new ChangeSoundSettingsListener()),
-        @SuppressWarnings("unchecked")
         BLOCKED_NOTIFICATIONS(R.string.app_notifications_blocked,
                 R.string.change_setting_action,
                 Predicate.TRUE,
diff --git a/src/com/android/deskclock/data/Weekdays.java b/src/com/android/deskclock/data/Weekdays.java
index b5ba73b97..118a6b0a9 100644
--- a/src/com/android/deskclock/data/Weekdays.java
+++ b/src/com/android/deskclock/data/Weekdays.java
@@ -17,6 +17,8 @@
 package com.android.deskclock.data;
 
 import android.content.Context;
+
+import androidx.annotation.NonNull;
 import androidx.annotation.VisibleForTesting;
 import android.util.ArrayMap;
 
@@ -242,6 +244,7 @@ public final class Weekdays {
         return mBits;
     }
 
+    @NonNull
     @Override
     public String toString() {
         final StringBuilder builder = new StringBuilder(19);
diff --git a/src/com/android/deskclock/provider/Alarm.java b/src/com/android/deskclock/provider/Alarm.java
index f560dea5d..5e0832509 100644
--- a/src/com/android/deskclock/provider/Alarm.java
+++ b/src/com/android/deskclock/provider/Alarm.java
@@ -26,6 +26,8 @@ import android.media.RingtoneManager;
 import android.net.Uri;
 import android.os.Parcel;
 import android.os.Parcelable;
+
+import androidx.annotation.NonNull;
 import android.os.ParcelUuid;
 import androidx.loader.content.CursorLoader;
 
@@ -464,6 +466,7 @@ public final class Alarm implements Parcelable, ClockContract.AlarmsColumns {
         return Long.valueOf(id).hashCode();
     }
 
+    @NonNull
     @Override
     public String toString() {
         return "Alarm{" +
diff --git a/src/com/android/deskclock/provider/AlarmInstance.java b/src/com/android/deskclock/provider/AlarmInstance.java
index a7502b740..d0a99168e 100644
--- a/src/com/android/deskclock/provider/AlarmInstance.java
+++ b/src/com/android/deskclock/provider/AlarmInstance.java
@@ -25,6 +25,8 @@ import android.database.Cursor;
 import android.media.RingtoneManager;
 import android.net.Uri;
 
+import androidx.annotation.NonNull;
+
 import com.android.deskclock.LogUtils;
 import com.android.deskclock.R;
 import com.android.deskclock.alarms.AlarmStateManager;
@@ -466,6 +468,7 @@ public final class AlarmInstance implements ClockContract.InstancesColumns {
         return Long.valueOf(mId).hashCode();
     }
 
+    @NonNull
     @Override
     public String toString() {
         return "AlarmInstance{" +
diff --git a/src/com/android/deskclock/ringtone/RingtonePickerActivity.java b/src/com/android/deskclock/ringtone/RingtonePickerActivity.java
index 94dc9baad..a6d7f2d43 100644
--- a/src/com/android/deskclock/ringtone/RingtonePickerActivity.java
+++ b/src/com/android/deskclock/ringtone/RingtonePickerActivity.java
@@ -44,6 +44,7 @@ import android.provider.MediaStore;
 import android.view.LayoutInflater;
 import android.view.MenuItem;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.VisibleForTesting;
 import androidx.appcompat.app.AlertDialog;
 import androidx.recyclerview.widget.LinearLayoutManager;
@@ -181,7 +182,7 @@ public class RingtonePickerActivity extends CollapsingToolbarBaseActivity
 
         mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() {
             @Override
-            public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
+            public void onScrollStateChanged(@NonNull RecyclerView recyclerView, int newState) {
                 if (mIndexOfRingtoneToRemove != RecyclerView.NO_POSITION) {
                     closeContextMenu();
                 }
@@ -241,7 +242,7 @@ public class RingtonePickerActivity extends CollapsingToolbarBaseActivity
     }
 
     @Override
-    protected void onSaveInstanceState(Bundle outState) {
+    protected void onSaveInstanceState(@NonNull Bundle outState) {
         super.onSaveInstanceState(outState);
 
         outState.putBoolean(STATE_KEY_PLAYING, mIsPlaying);
@@ -330,7 +331,7 @@ public class RingtonePickerActivity extends CollapsingToolbarBaseActivity
         return null;
     }
 
-    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
+    @VisibleForTesting
     RingtoneHolder getSelectedRingtoneHolder() {
         return getRingtoneHolder(mSelectedRingtoneUri);
     }
diff --git a/src/com/android/deskclock/settings/SimpleMenuPreference.java b/src/com/android/deskclock/settings/SimpleMenuPreference.java
index faead0f0f..9c8437f3f 100644
--- a/src/com/android/deskclock/settings/SimpleMenuPreference.java
+++ b/src/com/android/deskclock/settings/SimpleMenuPreference.java
@@ -54,6 +54,7 @@ public class SimpleMenuPreference extends DropDownPreference {
         super(context, attrs, defStyleAttr, defStyleRes);
     }
 
+    @NonNull
     @Override
     protected ArrayAdapter createAdapter() {
         mAdapter = new SimpleMenuAdapter(getContext(), R.layout.simple_menu_dropdown_item);
diff --git a/src/com/android/deskclock/stopwatch/LapsAdapter.java b/src/com/android/deskclock/stopwatch/LapsAdapter.java
index c20e10703..733ec766a 100644
--- a/src/com/android/deskclock/stopwatch/LapsAdapter.java
+++ b/src/com/android/deskclock/stopwatch/LapsAdapter.java
@@ -17,6 +17,8 @@
 package com.android.deskclock.stopwatch;
 
 import android.content.Context;
+
+import androidx.annotation.NonNull;
 import androidx.annotation.VisibleForTesting;
 import androidx.recyclerview.widget.RecyclerView;
 import android.text.format.DateUtils;
@@ -78,14 +80,15 @@ class LapsAdapter extends RecyclerView.Adapter<LapsAdapter.LapItemHolder> {
         return currentLapCount + lapCount;
     }
 
+    @NonNull
     @Override
-    public LapItemHolder onCreateViewHolder(ViewGroup parent, int viewType) {
+    public LapItemHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
         final View v = mInflater.inflate(R.layout.lap_view, parent, false /* attachToRoot */);
         return new LapItemHolder(v);
     }
 
     @Override
-    public void onBindViewHolder(LapItemHolder viewHolder, int position) {
+    public void onBindViewHolder(@NonNull LapItemHolder viewHolder, int position) {
         final long lapTime;
         final int lapNumber;
         final long totalTime;
diff --git a/src/com/android/deskclock/stopwatch/StopwatchFragment.java b/src/com/android/deskclock/stopwatch/StopwatchFragment.java
index ea04a167b..9bd6bda40 100644
--- a/src/com/android/deskclock/stopwatch/StopwatchFragment.java
+++ b/src/com/android/deskclock/stopwatch/StopwatchFragment.java
@@ -359,7 +359,6 @@ public final class StopwatchFragment extends DeskClockFragment {
         final String text = mLapsAdapter.getShareText();
 
         @SuppressLint("InlinedApi")
-        @SuppressWarnings("deprecation")
         final Intent shareIntent = new Intent(Intent.ACTION_SEND)
                 .addFlags(Intent.FLAG_ACTIVITY_NEW_DOCUMENT)
                 .putExtra(Intent.EXTRA_SUBJECT, subject)
@@ -649,7 +648,7 @@ public final class StopwatchFragment extends DeskClockFragment {
     private final class ScrollPositionWatcher extends RecyclerView.OnScrollListener
             implements View.OnLayoutChangeListener {
         @Override
-        public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
+        public void onScrolled(@NonNull RecyclerView recyclerView, int dx, int dy) {
             setTabScrolledToTop(Utils.isScrolledToTop(mLapsList));
         }
 
@@ -715,7 +714,7 @@ public final class StopwatchFragment extends DeskClockFragment {
         }
 
         @Override
-        public void onDrawOver(Canvas c, RecyclerView parent, RecyclerView.State state) {
+        public void onDrawOver(@NonNull Canvas c, @NonNull RecyclerView parent, @NonNull RecyclerView.State state) {
             super.onDrawOver(c, parent, state);
 
             final int w = parent.getWidth();
diff --git a/src/com/android/deskclock/timer/TimerFragment.java b/src/com/android/deskclock/timer/TimerFragment.java
index 702962703..ab74f4f04 100644
--- a/src/com/android/deskclock/timer/TimerFragment.java
+++ b/src/com/android/deskclock/timer/TimerFragment.java
@@ -227,7 +227,7 @@ public final class TimerFragment extends DeskClockFragment {
     }
 
     @Override
-    public void onSaveInstanceState(Bundle outState) {
+    public void onSaveInstanceState(@NonNull Bundle outState) {
         super.onSaveInstanceState(outState);
 
         // If the timer creation view is visible, store the input for later restoration.
diff --git a/src/com/android/deskclock/timer/TimerItemFragment.java b/src/com/android/deskclock/timer/TimerItemFragment.java
index 33b904285..ba52d4446 100644
--- a/src/com/android/deskclock/timer/TimerItemFragment.java
+++ b/src/com/android/deskclock/timer/TimerItemFragment.java
@@ -21,6 +21,8 @@ import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
+
+import androidx.annotation.NonNull;
 import androidx.fragment.app.Fragment;
 
 import com.android.deskclock.LabelDialogFragment;
@@ -54,8 +56,8 @@ public class TimerItemFragment extends Fragment {
     }
 
     @Override
-    public View onCreateView(LayoutInflater inflater, ViewGroup container,
-            Bundle savedInstanceState) {
+    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container,
+                             Bundle savedInstanceState) {
         final Timer timer = getTimer();
         if (timer == null) {
             return null;
diff --git a/src/com/android/deskclock/timer/TimerPagerAdapter.java b/src/com/android/deskclock/timer/TimerPagerAdapter.java
index f678866aa..2d9cf3f1d 100644
--- a/src/com/android/deskclock/timer/TimerPagerAdapter.java
+++ b/src/com/android/deskclock/timer/TimerPagerAdapter.java
@@ -20,6 +20,8 @@ import android.annotation.SuppressLint;
 import android.util.ArrayMap;
 import android.view.View;
 import android.view.ViewGroup;
+
+import androidx.annotation.NonNull;
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentTransaction;
@@ -58,12 +60,12 @@ class TimerPagerAdapter extends PagerAdapter implements TimerListener {
     }
 
     @Override
-    public boolean isViewFromObject(View view, Object object) {
+    public boolean isViewFromObject(@NonNull View view, @NonNull Object object) {
         return ((Fragment) object).getView() == view;
     }
 
     @Override
-    public int getItemPosition(Object object) {
+    public int getItemPosition(@NonNull Object object) {
         final TimerItemFragment fragment = (TimerItemFragment) object;
         final Timer timer = fragment.getTimer();
 
@@ -71,9 +73,10 @@ class TimerPagerAdapter extends PagerAdapter implements TimerListener {
         return position == -1 ? POSITION_NONE : position;
     }
 
+    @NonNull
     @Override
     @SuppressLint("CommitTransaction")
-    public Fragment instantiateItem(ViewGroup container, int position) {
+    public Fragment instantiateItem(@NonNull ViewGroup container, int position) {
         if (mCurrentTransaction == null) {
             mCurrentTransaction = mFragmentManager.beginTransaction();
         }
@@ -104,7 +107,7 @@ class TimerPagerAdapter extends PagerAdapter implements TimerListener {
 
     @Override
     @SuppressLint("CommitTransaction")
-    public void destroyItem(ViewGroup container, int position, Object object) {
+    public void destroyItem(@NonNull ViewGroup container, int position, @NonNull Object object) {
         final TimerItemFragment fragment = (TimerItemFragment) object;
 
         if (mCurrentTransaction == null) {
@@ -116,7 +119,7 @@ class TimerPagerAdapter extends PagerAdapter implements TimerListener {
     }
 
     @Override
-    public void setPrimaryItem(ViewGroup container, int position, Object object) {
+    public void setPrimaryItem(@NonNull ViewGroup container, int position, @NonNull Object object) {
         final Fragment fragment = (Fragment) object;
         if (fragment != mCurrentPrimaryItem) {
             if (mCurrentPrimaryItem != null) {
@@ -132,7 +135,7 @@ class TimerPagerAdapter extends PagerAdapter implements TimerListener {
     }
 
     @Override
-    public void finishUpdate(ViewGroup container) {
+    public void finishUpdate(@NonNull ViewGroup container) {
         if (mCurrentTransaction != null) {
             mCurrentTransaction.commitAllowingStateLoss();
             mCurrentTransaction = null;
diff --git a/src/com/android/deskclock/uidata/UiDataModel.java b/src/com/android/deskclock/uidata/UiDataModel.java
index c0d780696..8db9549e3 100644
--- a/src/com/android/deskclock/uidata/UiDataModel.java
+++ b/src/com/android/deskclock/uidata/UiDataModel.java
@@ -19,6 +19,8 @@ package com.android.deskclock.uidata;
 import android.content.Context;
 import android.content.SharedPreferences;
 import android.graphics.Typeface;
+
+import androidx.annotation.IdRes;
 import androidx.annotation.IntegerRes;
 import androidx.annotation.StringRes;
 
@@ -45,7 +47,7 @@ public final class UiDataModel {
         STOPWATCH(StopwatchFragment.class, R.id.page_stopwatch, R.string.menu_stopwatch);
 
         private final String mFragmentClassName;
-        private final @IntegerRes int mPageResId;
+        private final @IdRes int mPageResId;
         private final @StringRes int mLabelResId;
 
         Tab(Class fragmentClass, @IntegerRes int pageResId, @StringRes int labelResId) {
@@ -55,7 +57,7 @@ public final class UiDataModel {
         }
 
         public String getFragmentClassName() { return mFragmentClassName; }
-        public @IntegerRes int getPageResId() { return mPageResId; }
+        public @IdRes int getPageResId() { return mPageResId; }
         public @StringRes int getLabelResId() { return mLabelResId; }
     }
 
diff --git a/src/com/android/deskclock/widget/TextTime.java b/src/com/android/deskclock/widget/TextTime.java
index e0cea474b..e5a7b10d9 100644
--- a/src/com/android/deskclock/widget/TextTime.java
+++ b/src/com/android/deskclock/widget/TextTime.java
@@ -46,9 +46,9 @@ public class TextTime extends TextView {
     /** UTC does not have DST rules and will not alter the {@link #mHour} and {@link #mMinute}. */
     private static final TimeZone UTC = TimeZone.getTimeZone("UTC");
 
-    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
+    @VisibleForTesting
     static final CharSequence DEFAULT_FORMAT_12_HOUR = "h:mm a";
-    @VisibleForTesting(otherwise = VisibleForTesting.PRIVATE)
+    @VisibleForTesting
     static final CharSequence DEFAULT_FORMAT_24_HOUR = "H:mm";
 
     private CharSequence mFormat12;
diff --git a/src/com/android/deskclock/widget/toast/SnackbarSlidingBehavior.java b/src/com/android/deskclock/widget/toast/SnackbarSlidingBehavior.java
index 84cbcfffb..5db029d94 100644
--- a/src/com/android/deskclock/widget/toast/SnackbarSlidingBehavior.java
+++ b/src/com/android/deskclock/widget/toast/SnackbarSlidingBehavior.java
@@ -18,6 +18,7 @@ package com.android.deskclock.widget.toast;
 
 import android.content.Context;
 import androidx.annotation.Keep;
+import androidx.annotation.NonNull;
 import androidx.coordinatorlayout.widget.CoordinatorLayout;
 import com.google.android.material.snackbar.Snackbar;
 import android.util.AttributeSet;
@@ -33,23 +34,27 @@ public final class SnackbarSlidingBehavior extends CoordinatorLayout.Behavior<Vi
     }
 
     @Override
-    public boolean layoutDependsOn(CoordinatorLayout parent, View child, View dependency) {
+    public boolean layoutDependsOn(@NonNull CoordinatorLayout parent, @NonNull View child,
+                                   @NonNull View dependency) {
         return dependency instanceof Snackbar.SnackbarLayout;
     }
 
     @Override
-    public boolean onDependentViewChanged(CoordinatorLayout parent, View child, View dependency) {
+    public boolean onDependentViewChanged(@NonNull CoordinatorLayout parent, @NonNull View child,
+                                          @NonNull View dependency) {
         updateTranslationY(parent, child);
         return false;
     }
 
     @Override
-    public void onDependentViewRemoved(CoordinatorLayout parent, View child, View dependency) {
+    public void onDependentViewRemoved(@NonNull CoordinatorLayout parent, @NonNull View child,
+                                       @NonNull View dependency) {
         updateTranslationY(parent, child);
     }
 
     @Override
-    public boolean onLayoutChild(CoordinatorLayout parent, View child, int layoutDirection) {
+    public boolean onLayoutChild(@NonNull CoordinatorLayout parent, @NonNull View child,
+                                 int layoutDirection) {
         updateTranslationY(parent, child);
         return false;
     }
diff --git a/src/com/android/deskclock/worldclock/CitySelectionActivity.java b/src/com/android/deskclock/worldclock/CitySelectionActivity.java
index d923ad8fa..ef6fbf1fa 100644
--- a/src/com/android/deskclock/worldclock/CitySelectionActivity.java
+++ b/src/com/android/deskclock/worldclock/CitySelectionActivity.java
@@ -18,6 +18,8 @@ package com.android.deskclock.worldclock;
 
 import android.content.Context;
 import android.os.Bundle;
+
+import androidx.annotation.NonNull;
 import androidx.appcompat.widget.SearchView;
 import android.text.TextUtils;
 import android.text.format.DateFormat;
@@ -134,7 +136,7 @@ public final class CitySelectionActivity extends BaseActivity {
     }
 
     @Override
-    public void onSaveInstanceState(Bundle bundle) {
+    public void onSaveInstanceState(@NonNull Bundle bundle) {
         super.onSaveInstanceState(bundle);
         mSearchMenuItemController.saveInstance(bundle);
     }