Add typedefs and nullness annotations.

This changeset adds in typedef annotations (custom annotations
marked with @IntDef) for various int parameters and return values
in the API. It also adds nullness annotations for cases where the
documentation explicitly mentioned null policy, or where it was
blindingly obvious from the context. Also fixed some typos in the
documentation.

Change-Id: Ica27c01368895818e26237544edd8483007155bb

6 files changed, 160 insertions, 56 deletions

diff --git a/core/java/android/app/ActionBar.java b/core/java/android/app/ActionBar.java
index c4ddf1f..fbe8987 100644
--- a/core/java/android/app/ActionBar.java
+++ b/core/java/android/app/ActionBar.java
@@ -16,6 +16,9 @@
 
 package android.app;
 
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.content.Context;
 import android.content.res.TypedArray;
 import android.graphics.drawable.Drawable;
@@ -28,6 +31,9 @@ import android.view.ViewGroup.MarginLayoutParams;
 import android.view.Window;
 import android.widget.SpinnerAdapter;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 /**
  * A window feature at the top of the activity that may display the activity title, navigation
  * modes, and other interactive items.
@@ -57,6 +63,11 @@ import android.widget.SpinnerAdapter;
  * </div>
  */
 public abstract class ActionBar {
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef({NAVIGATION_MODE_STANDARD, NAVIGATION_MODE_LIST, NAVIGATION_MODE_TABS})
+    public @interface NavigationMode {}
+
     /**
      * Standard navigation mode. Consists of either a logo or icon
      * and title text with an optional subtitle. Clicking any of these elements
@@ -78,6 +89,19 @@ public abstract class ActionBar {
      */
     public static final int NAVIGATION_MODE_TABS = 2;
 
+    /** @hide */
+    @Retention(RetentionPolicy.SOURCE)
+    @IntDef(flag = true,
+            value = {
+                    DISPLAY_USE_LOGO,
+                    DISPLAY_SHOW_HOME,
+                    DISPLAY_HOME_AS_UP,
+                    DISPLAY_SHOW_TITLE,
+                    DISPLAY_SHOW_CUSTOM,
+                    DISPLAY_TITLE_MULTIPLE_LINES
+            })
+    public @interface DisplayOptions {}
+
     /**
      * Use logo instead of icon if available. This flag will cause appropriate
      * navigation modes to use a wider logo in place of the standard icon.
@@ -341,7 +365,7 @@ public abstract class ActionBar {
      * @param options A combination of the bits defined by the DISPLAY_ constants
      *                defined in ActionBar.
      */
-    public abstract void setDisplayOptions(int options);
+    public abstract void setDisplayOptions(@DisplayOptions int options);
     
     /**
      * Set selected display options. Only the options specified by mask will be changed.
@@ -356,7 +380,7 @@ public abstract class ActionBar {
      *                defined in ActionBar.
      * @param mask A bit mask declaring which display options should be changed.
      */
-    public abstract void setDisplayOptions(int options, int mask);
+    public abstract void setDisplayOptions(@DisplayOptions int options, @DisplayOptions int mask);
 
     /**
      * Set whether to display the activity logo rather than the activity icon.
@@ -431,7 +455,7 @@ public abstract class ActionBar {
      * @see #setStackedBackgroundDrawable(Drawable)
      * @see #setSplitBackgroundDrawable(Drawable)
      */
-    public abstract void setBackgroundDrawable(Drawable d);
+    public abstract void setBackgroundDrawable(@Nullable Drawable d);
 
     /**
      * Set the ActionBar's stacked background. This will appear
@@ -484,6 +508,7 @@ public abstract class ActionBar {
      *
      * @return The current navigation mode.
      */
+    @NavigationMode
     public abstract int getNavigationMode();
 
     /**
@@ -494,7 +519,7 @@ public abstract class ActionBar {
      * @see #NAVIGATION_MODE_LIST
      * @see #NAVIGATION_MODE_TABS
      */
-    public abstract void setNavigationMode(int mode);
+    public abstract void setNavigationMode(@NavigationMode int mode);
 
     /**
      * @return The current set of display options. 
@@ -1024,7 +1049,7 @@ public abstract class ActionBar {
         })
         public int gravity = Gravity.NO_GRAVITY;
 
-        public LayoutParams(Context c, AttributeSet attrs) {
+        public LayoutParams(@NonNull Context c, AttributeSet attrs) {
             super(c, attrs);
 
             TypedArray a = c.obtainStyledAttributes(attrs,
diff --git a/core/java/android/app/Activity.java b/core/java/android/app/Activity.java
index 57686a4..c2d35e7 100644
--- a/core/java/android/app/Activity.java
+++ b/core/java/android/app/Activity.java
@@ -16,11 +16,14 @@
 
 package android.app;
 
+import android.annotation.NonNull;
 import android.util.ArrayMap;
 import android.util.SuperNotCalledException;
 import com.android.internal.app.ActionBarImpl;
 import com.android.internal.policy.PolicyManager;
 
+import android.annotation.IntDef;
+import android.annotation.Nullable;
 import android.content.ComponentCallbacks2;
 import android.content.ComponentName;
 import android.content.ContentResolver;
@@ -83,6 +86,8 @@ import android.widget.AdapterView;
 
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
 import java.util.ArrayList;
 import java.util.HashMap;
 
@@ -851,6 +856,7 @@ public class Activity extends ContextThemeWrapper
      * @see #getWindow
      * @see android.view.Window#getCurrentFocus
      */
+    @Nullable
     public View getCurrentFocus() {
         return mWindow != null ? mWindow.getCurrentFocus() : null;
     }
@@ -881,7 +887,7 @@ public class Activity extends ContextThemeWrapper
      * @see #onRestoreInstanceState
      * @see #onPostCreate
      */
-    protected void onCreate(Bundle savedInstanceState) {
+    protected void onCreate(@Nullable Bundle savedInstanceState) {
         if (DEBUG_LIFECYCLE) Slog.v(TAG, "onCreate " + this + ": " + savedInstanceState);
         if (mLastNonConfigurationInstances != null) {
             mAllLoaderManagers = mLastNonConfigurationInstances.loaders;
@@ -1009,7 +1015,7 @@ public class Activity extends ContextThemeWrapper
      *     recently supplied in {@link #onSaveInstanceState}.  <b><i>Note: Otherwise it is null.</i></b>
      * @see #onCreate
      */
-    protected void onPostCreate(Bundle savedInstanceState) {
+    protected void onPostCreate(@Nullable Bundle savedInstanceState) {
         if (!isChild()) {
             mTitleReady = true;
             onTitleChanged(getTitle(), getTitleColor());
@@ -1346,6 +1352,7 @@ public class Activity extends ContextThemeWrapper
      * @see #onSaveInstanceState
      * @see #onPause
      */
+    @Nullable
     public CharSequence onCreateDescription() {
         return null;
     }
@@ -1548,6 +1555,7 @@ public class Activity extends ContextThemeWrapper
      * {@link Fragment#setRetainInstance(boolean)} instead; this is also
      * available on older platforms through the Android compatibility package.
      */
+    @Nullable
     @Deprecated
     public Object getLastNonConfigurationInstance() {
         return mLastNonConfigurationInstances != null
@@ -1627,6 +1635,7 @@ public class Activity extends ContextThemeWrapper
      * @return Returns the object previously returned by
      * {@link #onRetainNonConfigurationChildInstances()}
      */
+    @Nullable
     HashMap<String, Object> getLastNonConfigurationChildInstances() {
         return mLastNonConfigurationInstances != null
                 ? mLastNonConfigurationInstances.children : null;
@@ -1639,6 +1648,7 @@ public class Activity extends ContextThemeWrapper
      * set of child activities, such as ActivityGroup.  The same guarantees and restrictions apply
      * as for {@link #onRetainNonConfigurationInstance()}.  The default implementation returns null.
      */
+    @Nullable
     HashMap<String,Object> onRetainNonConfigurationChildInstances() {
         return null;
     }
@@ -1886,6 +1896,7 @@ public class Activity extends ContextThemeWrapper
      *
      * @return The Activity's ActionBar, or null if it does not have one.
      */
+    @Nullable
     public ActionBar getActionBar() {
         initActionBar();
         return mActionBar;
@@ -1982,7 +1993,17 @@ public class Activity extends ContextThemeWrapper
     public void setFinishOnTouchOutside(boolean finish) {
         mWindow.setCloseOnTouchOutside(finish);
     }
-    
+
+    /** @hide */
+    @IntDef({
+            DEFAULT_KEYS_DISABLE,
+            DEFAULT_KEYS_DIALER,
+            DEFAULT_KEYS_SHORTCUT,
+            DEFAULT_KEYS_SEARCH_LOCAL,
+            DEFAULT_KEYS_SEARCH_GLOBAL})
+    @Retention(RetentionPolicy.SOURCE)
+    @interface DefaultKeyMode {}
+
     /**
      * Use with {@link #setDefaultKeyMode} to turn off default handling of
      * keys.
@@ -2052,7 +2073,7 @@ public class Activity extends ContextThemeWrapper
      * @see #DEFAULT_KEYS_SEARCH_GLOBAL
      * @see #onKeyDown
      */
-    public final void setDefaultKeyMode(int mode) {
+    public final void setDefaultKeyMode(@DefaultKeyMode int mode) {
         mDefaultKeyMode = mode;
         
         // Some modes use a SpannableStringBuilder to track & dispatch input events
@@ -2518,6 +2539,7 @@ public class Activity extends ContextThemeWrapper
      * simply returns null so that all panel sub-windows will have the default
      * menu behavior.
      */
+    @Nullable
     public View onCreatePanelView(int featureId) {
         return null;
     }
@@ -3015,6 +3037,7 @@ public class Activity extends ContextThemeWrapper
      * {@link FragmentManager} instead; this is also
      * available on older platforms through the Android compatibility package.
      */
+    @Nullable
     @Deprecated
     protected Dialog onCreateDialog(int id, Bundle args) {
         return onCreateDialog(id);
@@ -3102,6 +3125,7 @@ public class Activity extends ContextThemeWrapper
      * {@link FragmentManager} instead; this is also
      * available on older platforms through the Android compatibility package.
      */
+    @Nullable
     @Deprecated
     public final boolean showDialog(int id, Bundle args) {
         if (mManagedDialogs == null) {
@@ -3223,13 +3247,13 @@ public class Activity extends ContextThemeWrapper
      * <p>It is typically called from onSearchRequested(), either directly from 
      * Activity.onSearchRequested() or from an overridden version in any given 
      * Activity.  If your goal is simply to activate search, it is preferred to call
-     * onSearchRequested(), which may have been overriden elsewhere in your Activity.  If your goal
+     * onSearchRequested(), which may have been overridden elsewhere in your Activity.  If your goal
      * is to inject specific data such as context data, it is preferred to <i>override</i>
      * onSearchRequested(), so that any callers to it will benefit from the override.
      * 
      * @param initialQuery Any non-null non-empty string will be inserted as 
      * pre-entered text in the search query box.
-     * @param selectInitialQuery If true, the intial query will be preselected, which means that
+     * @param selectInitialQuery If true, the initial query will be preselected, which means that
      * any further typing will replace it.  This is useful for cases where an entire pre-formed
      * query is being inserted.  If false, the selection point will be placed at the end of the
      * inserted query.  This is useful when the inserted query is text that the user entered,
@@ -3247,8 +3271,8 @@ public class Activity extends ContextThemeWrapper
      * @see android.app.SearchManager
      * @see #onSearchRequested
      */
-    public void startSearch(String initialQuery, boolean selectInitialQuery, 
-            Bundle appSearchData, boolean globalSearch) {
+    public void startSearch(@Nullable String initialQuery, boolean selectInitialQuery,
+            @Nullable Bundle appSearchData, boolean globalSearch) {
         ensureSearchManager();
         mSearchManager.startSearch(initialQuery, selectInitialQuery, getComponentName(),
                         appSearchData, globalSearch); 
@@ -3264,7 +3288,7 @@ public class Activity extends ContextThemeWrapper
      * searches.  This data will be returned with SEARCH intent(s).  Null if
      * no extra data is required.
      */
-    public void triggerSearch(String query, Bundle appSearchData) {
+    public void triggerSearch(String query, @Nullable Bundle appSearchData) {
         ensureSearchManager();
         mSearchManager.triggerSearch(query, getComponentName(), appSearchData);
     }
@@ -3331,6 +3355,7 @@ public class Activity extends ContextThemeWrapper
      * Convenience for calling
      * {@link android.view.Window#getLayoutInflater}.
      */
+    @NonNull
     public LayoutInflater getLayoutInflater() {
         return getWindow().getLayoutInflater();
     }
@@ -3338,6 +3363,7 @@ public class Activity extends ContextThemeWrapper
     /**
      * Returns a {@link MenuInflater} with this context.
      */
+    @NonNull
     public MenuInflater getMenuInflater() {
         // Make sure that action views can get an appropriate theme.
         if (mMenuInflater == null) {
@@ -3416,7 +3442,7 @@ public class Activity extends ContextThemeWrapper
      *
      * @see #startActivity 
      */
-    public void startActivityForResult(Intent intent, int requestCode, Bundle options) {
+    public void startActivityForResult(Intent intent, int requestCode, @Nullable Bundle options) {
         if (mParent == null) {
             Instrumentation.ActivityResult ar =
                 mInstrumentation.execStartActivity(
@@ -3495,7 +3521,7 @@ public class Activity extends ContextThemeWrapper
      * @param extraFlags Always set to 0.
      */
     public void startIntentSenderForResult(IntentSender intent, int requestCode,
-            Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags)
+            @Nullable Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags)
             throws IntentSender.SendIntentException {
         startIntentSenderForResult(intent, requestCode, fillInIntent, flagsMask,
                 flagsValues, extraFlags, null);
@@ -3527,7 +3553,7 @@ public class Activity extends ContextThemeWrapper
      * override any that conflict with those given by the IntentSender.
      */
     public void startIntentSenderForResult(IntentSender intent, int requestCode,
-            Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags,
+            @Nullable Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags,
             Bundle options) throws IntentSender.SendIntentException {
         if (mParent == null) {
             startIntentSenderForResultInner(intent, requestCode, fillInIntent,
@@ -3615,7 +3641,7 @@ public class Activity extends ContextThemeWrapper
      * @see #startActivityForResult 
      */
     @Override
-    public void startActivity(Intent intent, Bundle options) {
+    public void startActivity(Intent intent, @Nullable Bundle options) {
         if (options != null) {
             startActivityForResult(intent, -1, options);
         } else {
@@ -3664,7 +3690,7 @@ public class Activity extends ContextThemeWrapper
      * @see #startActivityForResult
      */
     @Override
-    public void startActivities(Intent[] intents, Bundle options) {
+    public void startActivities(Intent[] intents, @Nullable Bundle options) {
         mInstrumentation.execStartActivities(this, mMainThread.getApplicationThread(),
                 mToken, this, intents, options);
     }
@@ -3683,7 +3709,7 @@ public class Activity extends ContextThemeWrapper
      * @param extraFlags Always set to 0.
      */
     public void startIntentSender(IntentSender intent,
-            Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags)
+            @Nullable Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags)
             throws IntentSender.SendIntentException {
         startIntentSender(intent, fillInIntent, flagsMask, flagsValues,
                 extraFlags, null);
@@ -3710,7 +3736,7 @@ public class Activity extends ContextThemeWrapper
      * override any that conflict with those given by the IntentSender.
      */
     public void startIntentSender(IntentSender intent,
-            Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags,
+            @Nullable Intent fillInIntent, int flagsMask, int flagsValues, int extraFlags,
             Bundle options) throws IntentSender.SendIntentException {
         if (options != null) {
             startIntentSenderForResult(intent, -1, fillInIntent, flagsMask,
@@ -3738,7 +3764,7 @@ public class Activity extends ContextThemeWrapper
      * @see #startActivity
      * @see #startActivityForResult
      */
-    public boolean startActivityIfNeeded(Intent intent, int requestCode) {
+    public boolean startActivityIfNeeded(@NonNull Intent intent, int requestCode) {
         return startActivityIfNeeded(intent, requestCode, null);
     }
 
@@ -3772,7 +3798,8 @@ public class Activity extends ContextThemeWrapper
      * @see #startActivity
      * @see #startActivityForResult
      */
-    public boolean startActivityIfNeeded(Intent intent, int requestCode, Bundle options) {
+    public boolean startActivityIfNeeded(@NonNull Intent intent, int requestCode,
+            @Nullable Bundle options) {
         if (mParent == null) {
             int result = ActivityManager.START_RETURN_INTENT_TO_CALLER;
             try {
@@ -3821,7 +3848,7 @@ public class Activity extends ContextThemeWrapper
      * wasn't.  In general, if true is returned you will then want to call
      * finish() on yourself.
      */
-    public boolean startNextMatchingActivity(Intent intent) {
+    public boolean startNextMatchingActivity(@NonNull Intent intent) {
         return startNextMatchingActivity(intent, null);
     }
 
@@ -3844,7 +3871,7 @@ public class Activity extends ContextThemeWrapper
      * wasn't.  In general, if true is returned you will then want to call
      * finish() on yourself.
      */
-    public boolean startNextMatchingActivity(Intent intent, Bundle options) {
+    public boolean startNextMatchingActivity(@NonNull Intent intent, @Nullable Bundle options) {
         if (mParent == null) {
             try {
                 intent.migrateExtraStreamToClipData();
@@ -3874,7 +3901,7 @@ public class Activity extends ContextThemeWrapper
      * @see #startActivity
      * @see #startActivityForResult
      */
-    public void startActivityFromChild(Activity child, Intent intent,
+    public void startActivityFromChild(@NonNull Activity child, Intent intent,
             int requestCode) {
         startActivityFromChild(child, intent, requestCode, null);
     }
@@ -3898,8 +3925,8 @@ public class Activity extends ContextThemeWrapper
      * @see #startActivity 
      * @see #startActivityForResult 
      */
-    public void startActivityFromChild(Activity child, Intent intent, 
-            int requestCode, Bundle options) {
+    public void startActivityFromChild(@NonNull Activity child, Intent intent,
+            int requestCode, @Nullable Bundle options) {
         Instrumentation.ActivityResult ar =
             mInstrumentation.execStartActivity(
                 this, mMainThread.getApplicationThread(), mToken, child,
@@ -3924,7 +3951,7 @@ public class Activity extends ContextThemeWrapper
      * @see Fragment#startActivity
      * @see Fragment#startActivityForResult
      */
-    public void startActivityFromFragment(Fragment fragment, Intent intent, 
+    public void startActivityFromFragment(@NonNull Fragment fragment, Intent intent,
             int requestCode) {
         startActivityFromFragment(fragment, intent, requestCode, null);
     }
@@ -3949,8 +3976,8 @@ public class Activity extends ContextThemeWrapper
      * @see Fragment#startActivity 
      * @see Fragment#startActivityForResult 
      */
-    public void startActivityFromFragment(Fragment fragment, Intent intent, 
-            int requestCode, Bundle options) {
+    public void startActivityFromFragment(@NonNull Fragment fragment, Intent intent,
+            int requestCode, @Nullable Bundle options) {
         Instrumentation.ActivityResult ar =
             mInstrumentation.execStartActivity(
                 this, mMainThread.getApplicationThread(), mToken, fragment,
@@ -3982,7 +4009,7 @@ public class Activity extends ContextThemeWrapper
      */
     public void startIntentSenderFromChild(Activity child, IntentSender intent,
             int requestCode, Intent fillInIntent, int flagsMask, int flagsValues,
-            int extraFlags, Bundle options)
+            int extraFlags, @Nullable Bundle options)
             throws IntentSender.SendIntentException {
         startIntentSenderForResultInner(intent, requestCode, fillInIntent,
                 flagsMask, flagsValues, child, options);
@@ -4081,6 +4108,7 @@ public class Activity extends ContextThemeWrapper
      * @return The package of the activity that will receive your
      *         reply, or null if none.
      */
+    @Nullable
     public String getCallingPackage() {
         try {
             return ActivityManagerNative.getDefault().getCallingPackage(mToken);
@@ -4103,6 +4131,7 @@ public class Activity extends ContextThemeWrapper
      * @return The ComponentName of the activity that will receive your
      *         reply, or null if none.
      */
+    @Nullable
     public ComponentName getCallingActivity() {
         try {
             return ActivityManagerNative.getDefault().getCallingActivity(mToken);
@@ -4295,7 +4324,7 @@ public class Activity extends ContextThemeWrapper
      * @param requestCode Request code that had been used to start the
      *                    activity.
      */
-    public void finishActivityFromChild(Activity child, int requestCode) {
+    public void finishActivityFromChild(@NonNull Activity child, int requestCode) {
         try {
             ActivityManagerNative.getDefault()
                 .finishSubActivity(mToken, child.mEmbeddedID, requestCode);
@@ -4356,8 +4385,8 @@ public class Activity extends ContextThemeWrapper
      * 
      * @see PendingIntent
      */
-    public PendingIntent createPendingResult(int requestCode, Intent data,
-            int flags) {
+    public PendingIntent createPendingResult(int requestCode, @NonNull Intent data,
+            @PendingIntent.Flags int flags) {
         String packageName = getPackageName();
         try {
             data.prepareToLeaveProcess();
@@ -4384,7 +4413,7 @@ public class Activity extends ContextThemeWrapper
      * @param requestedOrientation An orientation constant as used in
      * {@link ActivityInfo#screenOrientation ActivityInfo.screenOrientation}.
      */
-    public void setRequestedOrientation(int requestedOrientation) {
+    public void setRequestedOrientation(@ActivityInfo.ScreenOrientation int requestedOrientation) {
         if (mParent == null) {
             try {
                 ActivityManagerNative.getDefault().setRequestedOrientation(
@@ -4406,6 +4435,7 @@ public class Activity extends ContextThemeWrapper
      * @return Returns an orientation constant as used in
      * {@link ActivityInfo#screenOrientation ActivityInfo.screenOrientation}.
      */
+    @ActivityInfo.ScreenOrientation
     public int getRequestedOrientation() {
         if (mParent == null) {
             try {
@@ -4477,6 +4507,7 @@ public class Activity extends ContextThemeWrapper
      * 
      * @return The local class name.
      */
+    @NonNull
     public String getLocalClassName() {
         final String pkg = getPackageName();
         final String cls = mComponent.getClassName();
@@ -4522,9 +4553,9 @@ public class Activity extends ContextThemeWrapper
         
         mSearchManager = new SearchManager(this, null);
     }
-    
+
     @Override
-    public Object getSystemService(String name) {
+    public Object getSystemService(@ServiceName @NonNull String name) {
         if (getBaseContext() == null) {
             throw new IllegalStateException(
                     "System services not available to Activities before onCreate()");
@@ -4686,7 +4717,7 @@ public class Activity extends ContextThemeWrapper
 
     /**
      * Gets the suggested audio stream whose volume should be changed by the
-     * harwdare volume controls.
+     * hardware volume controls.
      * 
      * @return The suggested audio stream type whose volume should be changed by
      *         the hardware volume controls.
@@ -4722,6 +4753,7 @@ public class Activity extends ContextThemeWrapper
      * @see android.view.LayoutInflater#createView
      * @see android.view.Window#getLayoutInflater
      */
+    @Nullable
     public View onCreateView(String name, Context context, AttributeSet attrs) {
         return null;
     }
@@ -4989,6 +5021,7 @@ public class Activity extends ContextThemeWrapper
      *
      * @see ActionMode
      */
+    @Nullable
     public ActionMode startActionMode(ActionMode.Callback callback) {
         return mWindow.getDecorView().startActionMode(callback);
     }
@@ -5004,6 +5037,7 @@ public class Activity extends ContextThemeWrapper
      * @return The new action mode, or <code>null</code> if the activity does not want to
      *         provide special handling for this action mode. (It will be handled by the system.)
      */
+    @Nullable
     @Override
     public ActionMode onWindowStartingActionMode(ActionMode.Callback callback) {
         initActionBar();
@@ -5147,6 +5181,7 @@ public class Activity extends ContextThemeWrapper
      * @return a new Intent targeting the defined parent of this activity or null if
      *         there is no valid parent.
      */
+    @Nullable
     public Intent getParentActivityIntent() {
         final String parentName = mActivityInfo.parentActivityName;
         if (TextUtils.isEmpty(parentName)) {
diff --git a/core/java/android/app/Fragment.java b/core/java/android/app/Fragment.java
index d626e5f..c09da87 100644
--- a/core/java/android/app/Fragment.java
+++ b/core/java/android/app/Fragment.java
@@ -17,6 +17,7 @@
 package android.app;
 
 import android.animation.Animator;
+import android.annotation.Nullable;
 import android.content.ComponentCallbacks2;
 import android.content.Context;
 import android.content.Intent;
@@ -575,7 +576,7 @@ public class Fragment implements ComponentCallbacks2, OnCreateContextMenuListene
      * the given fragment class.  This is a runtime exception; it is not
      * normally expected to happen.
      */
-    public static Fragment instantiate(Context context, String fname, Bundle args) {
+    public static Fragment instantiate(Context context, String fname, @Nullable Bundle args) {
         try {
             Class<?> clazz = sClassMap.get(fname);
             if (clazz == null) {
@@ -1213,7 +1214,8 @@ public class Fragment implements ComponentCallbacks2, OnCreateContextMenuListene
      * 
      * @return Return the View for the fragment's UI, or null.
      */
-    public View onCreateView(LayoutInflater inflater, ViewGroup container,
+    @Nullable
+    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container,
             Bundle savedInstanceState) {
         return null;
     }
@@ -1228,7 +1230,7 @@ public class Fragment implements ComponentCallbacks2, OnCreateContextMenuListene
      * @param savedInstanceState If non-null, this fragment is being re-constructed
      * from a previous saved state as given here.
      */
-    public void onViewCreated(View view, Bundle savedInstanceState) {
+    public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
     }
     
     /**
@@ -1237,6 +1239,7 @@ public class Fragment implements ComponentCallbacks2, OnCreateContextMenuListene
      * 
      * @return The fragment's root view, or null if it has no layout.
      */
+    @Nullable
     public View getView() {
         return mView;
     }
diff --git a/core/java/android/app/Notification.java b/core/java/android/app/Notification.java
index e70ad1c..45992e3 100644
--- a/core/java/android/app/Notification.java
+++ b/core/java/android/app/Notification.java
@@ -18,6 +18,7 @@ package android.app;
 
 import com.android.internal.R;
 
+import android.annotation.IntDef;
 import android.content.Context;
 import android.content.Intent;
 import android.content.res.Resources;
@@ -37,6 +38,8 @@ import android.view.View;
 import android.widget.ProgressBar;
 import android.widget.RemoteViews;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
 import java.text.NumberFormat;
 import java.util.ArrayList;
 
@@ -350,6 +353,11 @@ public class Notification implements Parcelable
 
     public int flags;
 
+    /** @hide */
+    @IntDef({PRIORITY_DEFAULT,PRIORITY_LOW,PRIORITY_MIN,PRIORITY_HIGH,PRIORITY_MAX})
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface Priority {}
+
     /**
      * Default notification {@link #priority}. If your application does not prioritize its own
      * notifications, use this value for all notifications.
@@ -391,6 +399,7 @@ public class Notification implements Parcelable
      * system will make a determination about how to interpret this priority when presenting
      * the notification.
      */
+    @Priority
     public int priority;
 
     /**
@@ -1434,7 +1443,7 @@ public class Notification implements Parcelable
          *
          * @see Notification#priority
          */
-        public Builder setPriority(int pri) {
+        public Builder setPriority(@Priority int pri) {
             mPriority = pri;
             return this;
         }
diff --git a/core/java/android/app/PendingIntent.java b/core/java/android/app/PendingIntent.java
index bdd0adb..a03e5b6 100644
--- a/core/java/android/app/PendingIntent.java
+++ b/core/java/android/app/PendingIntent.java
@@ -16,6 +16,9 @@
 
 package android.app;
 
+import android.annotation.IntDef;
+import android.annotation.NonNull;
+import android.annotation.Nullable;
 import android.content.Context;
 import android.content.Intent;
 import android.content.IIntentReceiver;
@@ -30,6 +33,9 @@ import android.os.Parcelable;
 import android.os.UserHandle;
 import android.util.AndroidException;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 /**
  * A description of an Intent and target action to perform with it.  Instances
  * of this class are created with {@link #getActivity}, {@link #getActivities},
@@ -86,6 +92,26 @@ import android.util.AndroidException;
 public final class PendingIntent implements Parcelable {
     private final IIntentSender mTarget;
 
+    /** @hide */
+    @IntDef(flag = true,
+            value = {
+                    FLAG_ONE_SHOT,
+                    FLAG_NO_CREATE,
+                    FLAG_CANCEL_CURRENT,
+                    FLAG_UPDATE_CURRENT,
+
+                    Intent.FILL_IN_ACTION,
+                    Intent.FILL_IN_DATA,
+                    Intent.FILL_IN_CATEGORIES,
+                    Intent.FILL_IN_COMPONENT,
+                    Intent.FILL_IN_PACKAGE,
+                    Intent.FILL_IN_SOURCE_BOUNDS,
+                    Intent.FILL_IN_SELECTOR,
+                    Intent.FILL_IN_CLIP_DATA
+            })
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface Flags {}
+
     /**
      * Flag for use with {@link #getActivity}, {@link #getBroadcast}, and
      * {@link #getService}: this
@@ -220,7 +246,7 @@ public final class PendingIntent implements Parcelable {
      * supplied.
      */
     public static PendingIntent getActivity(Context context, int requestCode,
-            Intent intent, int flags) {
+            Intent intent, @Flags int flags) {
         return getActivity(context, requestCode, intent, flags, null);
     }
 
@@ -253,7 +279,7 @@ public final class PendingIntent implements Parcelable {
      * supplied.
      */
     public static PendingIntent getActivity(Context context, int requestCode,
-            Intent intent, int flags, Bundle options) {
+            @NonNull Intent intent, @Flags int flags, @Nullable Bundle options) {
         String packageName = context.getPackageName();
         String resolvedType = intent != null ? intent.resolveTypeIfNeeded(
                 context.getContentResolver()) : null;
@@ -278,7 +304,7 @@ public final class PendingIntent implements Parcelable {
      * activity is started, not when the pending intent is created.
      */
     public static PendingIntent getActivityAsUser(Context context, int requestCode,
-            Intent intent, int flags, Bundle options, UserHandle user) {
+            @NonNull Intent intent, int flags, Bundle options, UserHandle user) {
         String packageName = context.getPackageName();
         String resolvedType = intent != null ? intent.resolveTypeIfNeeded(
                 context.getContentResolver()) : null;
@@ -343,7 +369,7 @@ public final class PendingIntent implements Parcelable {
      * supplied.
      */
     public static PendingIntent getActivities(Context context, int requestCode,
-            Intent[] intents, int flags) {
+            @NonNull Intent[] intents, @Flags int flags) {
         return getActivities(context, requestCode, intents, flags, null);
     }
 
@@ -393,7 +419,7 @@ public final class PendingIntent implements Parcelable {
      * supplied.
      */
     public static PendingIntent getActivities(Context context, int requestCode,
-            Intent[] intents, int flags, Bundle options) {
+            @NonNull Intent[] intents, @Flags int flags, @Nullable Bundle options) {
         String packageName = context.getPackageName();
         String[] resolvedTypes = new String[intents.length];
         for (int i=0; i<intents.length; i++) {
@@ -419,7 +445,7 @@ public final class PendingIntent implements Parcelable {
      * activity is started, not when the pending intent is created.
      */
     public static PendingIntent getActivitiesAsUser(Context context, int requestCode,
-            Intent[] intents, int flags, Bundle options, UserHandle user) {
+            @NonNull Intent[] intents, int flags, Bundle options, UserHandle user) {
         String packageName = context.getPackageName();
         String[] resolvedTypes = new String[intents.length];
         for (int i=0; i<intents.length; i++) {
@@ -463,7 +489,7 @@ public final class PendingIntent implements Parcelable {
      * supplied.
      */
     public static PendingIntent getBroadcast(Context context, int requestCode,
-            Intent intent, int flags) {
+            Intent intent, @Flags int flags) {
         return getBroadcastAsUser(context, requestCode, intent, flags,
                 new UserHandle(UserHandle.myUserId()));
     }
@@ -517,7 +543,7 @@ public final class PendingIntent implements Parcelable {
      * supplied.
      */
     public static PendingIntent getService(Context context, int requestCode,
-            Intent intent, int flags) {
+            @NonNull Intent intent, @Flags int flags) {
         String packageName = context.getPackageName();
         String resolvedType = intent != null ? intent.resolveTypeIfNeeded(
                 context.getContentResolver()) : null;
@@ -747,6 +773,7 @@ public final class PendingIntent implements Parcelable {
      * @return The package name of the PendingIntent, or null if there is
      * none associated with it.
      */
+    @Nullable
     public String getCreatorPackage() {
         try {
             return ActivityManagerNative.getDefault()
@@ -805,6 +832,7 @@ public final class PendingIntent implements Parcelable {
      * @return The user handle of the PendingIntent, or null if there is
      * none associated with it.
      */
+    @Nullable
     public UserHandle getCreatorUserHandle() {
         try {
             int uid = ActivityManagerNative.getDefault()
@@ -920,8 +948,8 @@ public final class PendingIntent implements Parcelable {
      * @param sender The PendingIntent to write, or null.
      * @param out Where to write the PendingIntent.
      */
-    public static void writePendingIntentOrNullToParcel(PendingIntent sender,
-            Parcel out) {
+    public static void writePendingIntentOrNullToParcel(@Nullable PendingIntent sender,
+            @NonNull Parcel out) {
         out.writeStrongBinder(sender != null ? sender.mTarget.asBinder()
                 : null);
     }
@@ -936,7 +964,8 @@ public final class PendingIntent implements Parcelable {
      * @return Returns the Messenger read from the Parcel, or null if null had
      * been written.
      */
-    public static PendingIntent readPendingIntentOrNullFromParcel(Parcel in) {
+    @Nullable
+    public static PendingIntent readPendingIntentOrNullFromParcel(@NonNull Parcel in) {
         IBinder b = in.readStrongBinder();
         return b != null ? new PendingIntent(b) : null;
     }
diff --git a/core/java/android/app/TaskStackBuilder.java b/core/java/android/app/TaskStackBuilder.java
index 3e0ac7e..0077db1 100644
--- a/core/java/android/app/TaskStackBuilder.java
+++ b/core/java/android/app/TaskStackBuilder.java
@@ -16,6 +16,7 @@
 
 package android.app;
 
+import android.annotation.NonNull;
 import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
@@ -244,7 +245,7 @@ public class TaskStackBuilder {
      *
      * @return The obtained PendingIntent
      */
-    public PendingIntent getPendingIntent(int requestCode, int flags) {
+    public PendingIntent getPendingIntent(int requestCode, @PendingIntent.Flags int flags) {
         return getPendingIntent(requestCode, flags, null);
     }
 
@@ -263,7 +264,8 @@ public class TaskStackBuilder {
      *
      * @return The obtained PendingIntent
      */
-    public PendingIntent getPendingIntent(int requestCode, int flags, Bundle options) {
+    public PendingIntent getPendingIntent(int requestCode, @PendingIntent.Flags int flags,
+            Bundle options) {
         if (mIntents.isEmpty()) {
             throw new IllegalStateException(
                     "No intents added to TaskStackBuilder; cannot getPendingIntent");
@@ -294,6 +296,7 @@ public class TaskStackBuilder {
      *
      * @return An array containing the intents added to this builder.
      */
+    @NonNull
     public Intent[] getIntents() {
         Intent[] intents = new Intent[mIntents.size()];
         if (intents.length == 0) return intents;