diff --git a/api/current.txt b/api/current.txt
index a888b08..a529a0f 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -13072,19 +13072,19 @@
     method public String buildUnionSubQuery(String, String[], java.util.Set<java.lang.String>, int, String, String, String, String);
     method @Deprecated public String buildUnionSubQuery(String, String[], java.util.Set<java.lang.String>, int, String, String, String[], String, String);
     method public int delete(@NonNull android.database.sqlite.SQLiteDatabase, @Nullable String, @Nullable String[]);
-    method public android.database.sqlite.SQLiteDatabase.CursorFactory getCursorFactory();
+    method @Nullable public android.database.sqlite.SQLiteDatabase.CursorFactory getCursorFactory();
     method public boolean getDistinct();
-    method public java.util.Map<java.lang.String,java.lang.String> getProjectionMap();
+    method @Nullable public java.util.Map<java.lang.String,java.lang.String> getProjectionMap();
     method public boolean getStrict();
-    method public String getTables();
+    method @Nullable public String getTables();
     method public android.database.Cursor query(android.database.sqlite.SQLiteDatabase, String[], String, String[], String, String, String);
     method public android.database.Cursor query(android.database.sqlite.SQLiteDatabase, String[], String, String[], String, String, String, String);
     method public android.database.Cursor query(android.database.sqlite.SQLiteDatabase, String[], String, String[], String, String, String, String, android.os.CancellationSignal);
-    method public void setCursorFactory(android.database.sqlite.SQLiteDatabase.CursorFactory);
+    method public void setCursorFactory(@Nullable android.database.sqlite.SQLiteDatabase.CursorFactory);
     method public void setDistinct(boolean);
-    method public void setProjectionMap(java.util.Map<java.lang.String,java.lang.String>);
+    method public void setProjectionMap(@Nullable java.util.Map<java.lang.String,java.lang.String>);
     method public void setStrict(boolean);
-    method public void setTables(String);
+    method public void setTables(@Nullable String);
     method public int update(@NonNull android.database.sqlite.SQLiteDatabase, @NonNull android.content.ContentValues, @Nullable String, @Nullable String[]);
   }
 
@@ -34585,7 +34585,7 @@
     method public static java.io.File getExternalStoragePublicDirectory(String);
     method public static String getExternalStorageState();
     method public static String getExternalStorageState(java.io.File);
-    method public static java.io.File getRootDirectory();
+    method @NonNull public static java.io.File getRootDirectory();
     method @Deprecated public static String getStorageState(java.io.File);
     method public static boolean isExternalStorageEmulated();
     method public static boolean isExternalStorageEmulated(java.io.File);
@@ -35311,27 +35311,27 @@
     ctor public StrictMode.ThreadPolicy.Builder();
     ctor public StrictMode.ThreadPolicy.Builder(android.os.StrictMode.ThreadPolicy);
     method public android.os.StrictMode.ThreadPolicy build();
-    method public android.os.StrictMode.ThreadPolicy.Builder detectAll();
-    method public android.os.StrictMode.ThreadPolicy.Builder detectCustomSlowCalls();
-    method public android.os.StrictMode.ThreadPolicy.Builder detectDiskReads();
-    method public android.os.StrictMode.ThreadPolicy.Builder detectDiskWrites();
-    method public android.os.StrictMode.ThreadPolicy.Builder detectNetwork();
-    method public android.os.StrictMode.ThreadPolicy.Builder detectResourceMismatches();
-    method public android.os.StrictMode.ThreadPolicy.Builder detectUnbufferedIo();
-    method public android.os.StrictMode.ThreadPolicy.Builder penaltyDeath();
-    method public android.os.StrictMode.ThreadPolicy.Builder penaltyDeathOnNetwork();
-    method public android.os.StrictMode.ThreadPolicy.Builder penaltyDialog();
-    method public android.os.StrictMode.ThreadPolicy.Builder penaltyDropBox();
-    method public android.os.StrictMode.ThreadPolicy.Builder penaltyFlashScreen();
-    method public android.os.StrictMode.ThreadPolicy.Builder penaltyListener(@NonNull java.util.concurrent.Executor, @NonNull android.os.StrictMode.OnThreadViolationListener);
-    method public android.os.StrictMode.ThreadPolicy.Builder penaltyLog();
-    method public android.os.StrictMode.ThreadPolicy.Builder permitAll();
-    method public android.os.StrictMode.ThreadPolicy.Builder permitCustomSlowCalls();
-    method public android.os.StrictMode.ThreadPolicy.Builder permitDiskReads();
-    method public android.os.StrictMode.ThreadPolicy.Builder permitDiskWrites();
-    method public android.os.StrictMode.ThreadPolicy.Builder permitNetwork();
-    method public android.os.StrictMode.ThreadPolicy.Builder permitResourceMismatches();
-    method public android.os.StrictMode.ThreadPolicy.Builder permitUnbufferedIo();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder detectAll();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder detectCustomSlowCalls();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder detectDiskReads();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder detectDiskWrites();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder detectNetwork();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder detectResourceMismatches();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder detectUnbufferedIo();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder penaltyDeath();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder penaltyDeathOnNetwork();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder penaltyDialog();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder penaltyDropBox();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder penaltyFlashScreen();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder penaltyListener(@NonNull java.util.concurrent.Executor, @NonNull android.os.StrictMode.OnThreadViolationListener);
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder penaltyLog();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder permitAll();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder permitCustomSlowCalls();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder permitDiskReads();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder permitDiskWrites();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder permitNetwork();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder permitResourceMismatches();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder permitUnbufferedIo();
   }
 
   public static final class StrictMode.VmPolicy {
@@ -35342,26 +35342,26 @@
     ctor public StrictMode.VmPolicy.Builder();
     ctor public StrictMode.VmPolicy.Builder(android.os.StrictMode.VmPolicy);
     method public android.os.StrictMode.VmPolicy build();
-    method public android.os.StrictMode.VmPolicy.Builder detectActivityLeaks();
-    method public android.os.StrictMode.VmPolicy.Builder detectAll();
-    method public android.os.StrictMode.VmPolicy.Builder detectCleartextNetwork();
-    method public android.os.StrictMode.VmPolicy.Builder detectContentUriWithoutPermission();
-    method public android.os.StrictMode.VmPolicy.Builder detectCredentialProtectedWhileLocked();
-    method public android.os.StrictMode.VmPolicy.Builder detectFileUriExposure();
-    method public android.os.StrictMode.VmPolicy.Builder detectImplicitDirectBoot();
-    method public android.os.StrictMode.VmPolicy.Builder detectLeakedClosableObjects();
-    method public android.os.StrictMode.VmPolicy.Builder detectLeakedRegistrationObjects();
-    method public android.os.StrictMode.VmPolicy.Builder detectLeakedSqlLiteObjects();
-    method public android.os.StrictMode.VmPolicy.Builder detectNonSdkApiUsage();
-    method public android.os.StrictMode.VmPolicy.Builder detectUntaggedSockets();
-    method public android.os.StrictMode.VmPolicy.Builder penaltyDeath();
-    method public android.os.StrictMode.VmPolicy.Builder penaltyDeathOnCleartextNetwork();
-    method public android.os.StrictMode.VmPolicy.Builder penaltyDeathOnFileUriExposure();
-    method public android.os.StrictMode.VmPolicy.Builder penaltyDropBox();
-    method public android.os.StrictMode.VmPolicy.Builder penaltyListener(@NonNull java.util.concurrent.Executor, @NonNull android.os.StrictMode.OnVmViolationListener);
-    method public android.os.StrictMode.VmPolicy.Builder penaltyLog();
-    method public android.os.StrictMode.VmPolicy.Builder permitNonSdkApiUsage();
-    method public android.os.StrictMode.VmPolicy.Builder setClassInstanceLimit(Class, int);
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectActivityLeaks();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectAll();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectCleartextNetwork();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectContentUriWithoutPermission();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectCredentialProtectedWhileLocked();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectFileUriExposure();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectImplicitDirectBoot();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectLeakedClosableObjects();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectLeakedRegistrationObjects();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectLeakedSqlLiteObjects();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectNonSdkApiUsage();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder detectUntaggedSockets();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder penaltyDeath();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder penaltyDeathOnCleartextNetwork();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder penaltyDeathOnFileUriExposure();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder penaltyDropBox();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder penaltyListener(@NonNull java.util.concurrent.Executor, @NonNull android.os.StrictMode.OnVmViolationListener);
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder penaltyLog();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder permitNonSdkApiUsage();
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder setClassInstanceLimit(Class, int);
   }
 
   public final class SystemClock {
@@ -38407,10 +38407,10 @@
 
   public final class MediaStore {
     ctor public MediaStore();
-    method @NonNull public static java.util.Set<java.lang.String> getAllVolumeNames(android.content.Context);
-    method public static android.net.Uri getDocumentUri(android.content.Context, android.net.Uri);
+    method @NonNull public static java.util.Set<java.lang.String> getAllVolumeNames(@NonNull android.content.Context);
+    method @Nullable public static android.net.Uri getDocumentUri(@NonNull android.content.Context, @NonNull android.net.Uri);
     method public static android.net.Uri getMediaScannerUri();
-    method public static android.net.Uri getMediaUri(android.content.Context, android.net.Uri);
+    method @Nullable public static android.net.Uri getMediaUri(@NonNull android.content.Context, @NonNull android.net.Uri);
     method public static String getVersion(android.content.Context);
     method @NonNull public static String getVolumeName(@NonNull android.net.Uri);
     method @NonNull public static android.net.Uri setIncludePending(@NonNull android.net.Uri);
diff --git a/api/removed.txt b/api/removed.txt
index 40b1316..31dda47 100644
--- a/api/removed.txt
+++ b/api/removed.txt
@@ -352,11 +352,11 @@
   }
 
   public static final class StrictMode.ThreadPolicy.Builder {
-    method public android.os.StrictMode.ThreadPolicy.Builder penaltyListener(@NonNull android.os.StrictMode.OnThreadViolationListener, @NonNull java.util.concurrent.Executor);
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder penaltyListener(@NonNull android.os.StrictMode.OnThreadViolationListener, @NonNull java.util.concurrent.Executor);
   }
 
   public static final class StrictMode.VmPolicy.Builder {
-    method public android.os.StrictMode.VmPolicy.Builder penaltyListener(@NonNull android.os.StrictMode.OnVmViolationListener, @NonNull java.util.concurrent.Executor);
+    method @NonNull public android.os.StrictMode.VmPolicy.Builder penaltyListener(@NonNull android.os.StrictMode.OnVmViolationListener, @NonNull java.util.concurrent.Executor);
   }
 
   public final class SystemClock {
diff --git a/api/system-current.txt b/api/system-current.txt
index 8325cbc..ec7cea9 100644
--- a/api/system-current.txt
+++ b/api/system-current.txt
@@ -5210,11 +5210,11 @@
   }
 
   public class Environment {
-    method public static java.io.File getOdmDirectory();
-    method public static java.io.File getOemDirectory();
-    method public static java.io.File getProductDirectory();
-    method public static java.io.File getProductServicesDirectory();
-    method public static java.io.File getVendorDirectory();
+    method @NonNull public static java.io.File getOdmDirectory();
+    method @NonNull public static java.io.File getOemDirectory();
+    method @NonNull public static java.io.File getProductDirectory();
+    method @NonNull public static java.io.File getProductServicesDirectory();
+    method @NonNull public static java.io.File getVendorDirectory();
   }
 
   public class HidlSupport {
diff --git a/api/test-current.txt b/api/test-current.txt
index c5e535e..89a2a4c 100644
--- a/api/test-current.txt
+++ b/api/test-current.txt
@@ -1416,8 +1416,8 @@
 
   public class Environment {
     method public static java.io.File buildPath(java.io.File, java.lang.String...);
-    method public static java.io.File getProductDirectory();
-    method public static java.io.File getStorageDirectory();
+    method @NonNull public static java.io.File getProductDirectory();
+    method @NonNull public static java.io.File getStorageDirectory();
   }
 
   public final class FileUtils {
@@ -1666,7 +1666,7 @@
   }
 
   public static final class StrictMode.ThreadPolicy.Builder {
-    method public android.os.StrictMode.ThreadPolicy.Builder detectExplicitGc();
+    method @NonNull public android.os.StrictMode.ThreadPolicy.Builder detectExplicitGc();
   }
 
   public static final class StrictMode.ViolationInfo implements android.os.Parcelable {
diff --git a/core/java/android/database/sqlite/SQLiteQueryBuilder.java b/core/java/android/database/sqlite/SQLiteQueryBuilder.java
index 03e8507..a73a719 100644
--- a/core/java/android/database/sqlite/SQLiteQueryBuilder.java
+++ b/core/java/android/database/sqlite/SQLiteQueryBuilder.java
@@ -89,7 +89,7 @@
      *
      * @return the list of tables being queried
      */
-    public String getTables() {
+    public @Nullable String getTables() {
         return mTables;
     }
 
@@ -101,7 +101,7 @@
      *
      * @param inTables the list of tables to query on
      */
-    public void setTables(String inTables) {
+    public void setTables(@Nullable String inTables) {
         mTables = inTables;
     }
 
@@ -170,7 +170,7 @@
      *
      * @param columnMap maps from the user column names to the database column names
      */
-    public void setProjectionMap(Map<String, String> columnMap) {
+    public void setProjectionMap(@Nullable Map<String, String> columnMap) {
         mProjectionMap = columnMap;
     }
 
@@ -178,7 +178,7 @@
      * Gets the projection map for the query, as last configured by
      * {@link #setProjectionMap(Map)}.
      */
-    public Map<String, String> getProjectionMap() {
+    public @Nullable Map<String, String> getProjectionMap() {
         return mProjectionMap;
     }
 
@@ -189,7 +189,7 @@
      *
      * @hide
      */
-    public void setProjectionGreylist(List<Pattern> projectionGreylist) {
+    public void setProjectionGreylist(@Nullable List<Pattern> projectionGreylist) {
         mProjectionGreylist = projectionGreylist;
     }
 
@@ -199,7 +199,7 @@
      *
      * @hide
      */
-    public List<Pattern> getProjectionGreylist() {
+    public @Nullable List<Pattern> getProjectionGreylist() {
         return mProjectionGreylist;
     }
 
@@ -210,7 +210,7 @@
      *
      * @param factory the factory to use.
      */
-    public void setCursorFactory(SQLiteDatabase.CursorFactory factory) {
+    public void setCursorFactory(@Nullable SQLiteDatabase.CursorFactory factory) {
         mFactory = factory;
     }
 
@@ -218,7 +218,7 @@
      * Sets the cursor factory to be used for the query, as last configured by
      * {@link #setCursorFactory(android.database.sqlite.SQLiteDatabase.CursorFactory)}.
      */
-    public SQLiteDatabase.CursorFactory getCursorFactory() {
+    public @Nullable SQLiteDatabase.CursorFactory getCursorFactory() {
         return mFactory;
     }
 
diff --git a/core/java/android/os/Environment.java b/core/java/android/os/Environment.java
index 0aed981..b3e35b6 100644
--- a/core/java/android/os/Environment.java
+++ b/core/java/android/os/Environment.java
@@ -16,6 +16,7 @@
 
 package android.os;
 
+import android.annotation.NonNull;
 import android.annotation.SystemApi;
 import android.annotation.TestApi;
 import android.app.admin.DevicePolicyManager;
@@ -155,13 +156,13 @@
      * Return root of the "system" partition holding the core Android OS.
      * Always present and mounted read-only.
      */
-    public static File getRootDirectory() {
+    public static @NonNull File getRootDirectory() {
         return DIR_ANDROID_ROOT;
     }
 
     /** {@hide} */
     @TestApi
-    public static File getStorageDirectory() {
+    public static @NonNull File getStorageDirectory() {
         return DIR_ANDROID_STORAGE;
     }
 
@@ -172,7 +173,7 @@
      * @hide
      */
     @SystemApi
-    public static File getOemDirectory() {
+    public static @NonNull File getOemDirectory() {
         return DIR_OEM_ROOT;
     }
 
@@ -183,7 +184,7 @@
      * @hide
      */
     @SystemApi
-    public static File getOdmDirectory() {
+    public static @NonNull File getOdmDirectory() {
         return DIR_ODM_ROOT;
     }
 
@@ -193,7 +194,7 @@
      * @hide
      */
     @SystemApi
-    public static File getVendorDirectory() {
+    public static @NonNull File getVendorDirectory() {
         return DIR_VENDOR_ROOT;
     }
 
@@ -205,7 +206,7 @@
      */
     @SystemApi
     @TestApi
-    public static File getProductDirectory() {
+    public static @NonNull File getProductDirectory() {
         return DIR_PRODUCT_ROOT;
     }
 
@@ -216,7 +217,7 @@
      * @hide
      */
     @SystemApi
-    public static File getProductServicesDirectory() {
+    public static @NonNull File getProductServicesDirectory() {
         return DIR_PRODUCT_SERVICES_ROOT;
     }
 
diff --git a/core/java/android/os/StrictMode.java b/core/java/android/os/StrictMode.java
index 5ff6e55..49d95df 100644
--- a/core/java/android/os/StrictMode.java
+++ b/core/java/android/os/StrictMode.java
@@ -482,7 +482,7 @@
              * <p>As of the Gingerbread release this includes network and disk operations but will
              * likely expand in future releases.
              */
-            public Builder detectAll() {
+            public @NonNull Builder detectAll() {
                 detectDiskReads();
                 detectDiskWrites();
                 detectNetwork();
@@ -501,52 +501,52 @@
             }
 
             /** Disable the detection of everything. */
-            public Builder permitAll() {
+            public @NonNull Builder permitAll() {
                 return disable(DETECT_THREAD_ALL);
             }
 
             /** Enable detection of network operations. */
-            public Builder detectNetwork() {
+            public @NonNull Builder detectNetwork() {
                 return enable(DETECT_THREAD_NETWORK);
             }
 
             /** Disable detection of network operations. */
-            public Builder permitNetwork() {
+            public @NonNull Builder permitNetwork() {
                 return disable(DETECT_THREAD_NETWORK);
             }
 
             /** Enable detection of disk reads. */
-            public Builder detectDiskReads() {
+            public @NonNull Builder detectDiskReads() {
                 return enable(DETECT_THREAD_DISK_READ);
             }
 
             /** Disable detection of disk reads. */
-            public Builder permitDiskReads() {
+            public @NonNull Builder permitDiskReads() {
                 return disable(DETECT_THREAD_DISK_READ);
             }
 
             /** Enable detection of slow calls. */
-            public Builder detectCustomSlowCalls() {
+            public @NonNull Builder detectCustomSlowCalls() {
                 return enable(DETECT_THREAD_CUSTOM);
             }
 
             /** Disable detection of slow calls. */
-            public Builder permitCustomSlowCalls() {
+            public @NonNull Builder permitCustomSlowCalls() {
                 return disable(DETECT_THREAD_CUSTOM);
             }
 
             /** Disable detection of mismatches between defined resource types and getter calls. */
-            public Builder permitResourceMismatches() {
+            public @NonNull Builder permitResourceMismatches() {
                 return disable(DETECT_THREAD_RESOURCE_MISMATCH);
             }
 
             /** Detect unbuffered input/output operations. */
-            public Builder detectUnbufferedIo() {
+            public @NonNull Builder detectUnbufferedIo() {
                 return enable(DETECT_THREAD_UNBUFFERED_IO);
             }
 
             /** Disable detection of unbuffered input/output operations. */
-            public Builder permitUnbufferedIo() {
+            public @NonNull Builder permitUnbufferedIo() {
                 return disable(DETECT_THREAD_UNBUFFERED_IO);
             }
 
@@ -562,17 +562,17 @@
              * call will return a value without crashing; however, the developer should format the
              * resource as an integer to avoid unnecessary type conversion.
              */
-            public Builder detectResourceMismatches() {
+            public @NonNull Builder detectResourceMismatches() {
                 return enable(DETECT_THREAD_RESOURCE_MISMATCH);
             }
 
             /** Enable detection of disk writes. */
-            public Builder detectDiskWrites() {
+            public @NonNull Builder detectDiskWrites() {
                 return enable(DETECT_THREAD_DISK_WRITE);
             }
 
             /** Disable detection of disk writes. */
-            public Builder permitDiskWrites() {
+            public @NonNull Builder permitDiskWrites() {
                 return disable(DETECT_THREAD_DISK_WRITE);
             }
 
@@ -582,7 +582,7 @@
              * @hide
              */
             @TestApi
-            public Builder detectExplicitGc() {
+            public @NonNull Builder detectExplicitGc() {
                 // TODO(b/3400644): Un-hide this for next API update
                 // TODO(b/3400644): Un-hide ExplicitGcViolation for next API update
                 // TODO(b/3400644): Make DETECT_EXPLICIT_GC a @TestApi for next API update
@@ -595,7 +595,7 @@
              *
              * @hide
              */
-            public Builder permitExplicitGc() {
+            public @NonNull Builder permitExplicitGc() {
                 // TODO(b/3400644): Un-hide this for next API update
                 return disable(DETECT_THREAD_EXPLICIT_GC);
             }
@@ -604,7 +604,7 @@
              * Show an annoying dialog to the developer on detected violations, rate-limited to be
              * only a little annoying.
              */
-            public Builder penaltyDialog() {
+            public @NonNull Builder penaltyDialog() {
                 return enable(PENALTY_DIALOG);
             }
 
@@ -616,7 +616,7 @@
              * <p>Unlike {@link #penaltyDeathOnNetwork}, this applies to disk reads, disk writes,
              * and network usage if their corresponding detect flags are set.
              */
-            public Builder penaltyDeath() {
+            public @NonNull Builder penaltyDeath() {
                 return enable(PENALTY_DEATH);
             }
 
@@ -627,17 +627,17 @@
              *
              * <p>In the Honeycomb or later SDKs, this is on by default.
              */
-            public Builder penaltyDeathOnNetwork() {
+            public @NonNull Builder penaltyDeathOnNetwork() {
                 return enable(PENALTY_DEATH_ON_NETWORK);
             }
 
             /** Flash the screen during a violation. */
-            public Builder penaltyFlashScreen() {
+            public @NonNull Builder penaltyFlashScreen() {
                 return enable(PENALTY_FLASH);
             }
 
             /** Log detected violations to the system log. */
-            public Builder penaltyLog() {
+            public @NonNull Builder penaltyLog() {
                 return enable(PENALTY_LOG);
             }
 
@@ -646,7 +646,7 @@
              * android.os.DropBoxManager DropBox} on policy violation. Intended mostly for platform
              * integrators doing beta user field data collection.
              */
-            public Builder penaltyDropBox() {
+            public @NonNull Builder penaltyDropBox() {
                 return enable(PENALTY_DROPBOX);
             }
 
@@ -654,7 +654,7 @@
              * Call #{@link OnThreadViolationListener#onThreadViolation(Violation)} on specified
              * executor every violation.
              */
-            public Builder penaltyListener(
+            public @NonNull Builder penaltyListener(
                     @NonNull Executor executor, @NonNull OnThreadViolationListener listener) {
                 if (executor == null) {
                     throw new NullPointerException("executor must not be null");
@@ -665,7 +665,7 @@
             }
 
             /** @removed */
-            public Builder penaltyListener(
+            public @NonNull Builder penaltyListener(
                     @NonNull OnThreadViolationListener listener, @NonNull Executor executor) {
                 return penaltyListener(executor, listener);
             }
@@ -782,7 +782,7 @@
              * Set an upper bound on how many instances of a class can be in memory at once. Helps
              * to prevent object leaks.
              */
-            public Builder setClassInstanceLimit(Class klass, int instanceLimit) {
+            public @NonNull Builder setClassInstanceLimit(Class klass, int instanceLimit) {
                 if (klass == null) {
                     throw new NullPointerException("klass == null");
                 }
@@ -803,12 +803,12 @@
             }
 
             /** Detect leaks of {@link android.app.Activity} subclasses. */
-            public Builder detectActivityLeaks() {
+            public @NonNull Builder detectActivityLeaks() {
                 return enable(DETECT_VM_ACTIVITY_LEAKS);
             }
 
             /** @hide */
-            public Builder permitActivityLeaks() {
+            public @NonNull Builder permitActivityLeaks() {
                 return disable(DETECT_VM_ACTIVITY_LEAKS);
             }
 
@@ -819,7 +819,7 @@
              * enabled may not be detected. To ensure that all such API accesses are detected,
              * you should apply this policy as early as possible after process creation.
              */
-            public Builder detectNonSdkApiUsage() {
+            public @NonNull Builder detectNonSdkApiUsage() {
                 return enable(DETECT_VM_NON_SDK_API_USAGE);
             }
 
@@ -829,7 +829,7 @@
              * continue to restrict or warn on access to methods that are not part of the
              * public SDK.
              */
-            public Builder permitNonSdkApiUsage() {
+            public @NonNull Builder permitNonSdkApiUsage() {
                 return disable(DETECT_VM_NON_SDK_API_USAGE);
             }
 
@@ -839,7 +839,7 @@
              * <p>In the Honeycomb release this includes leaks of SQLite cursors, Activities, and
              * other closable objects but will likely expand in future releases.
              */
-            public Builder detectAll() {
+            public @NonNull Builder detectAll() {
                 detectLeakedSqlLiteObjects();
 
                 final int targetSdk = VMRuntime.getRuntime().getTargetSdkVersion();
@@ -881,7 +881,7 @@
              * <p>You always want to explicitly close your SQLite cursors to avoid unnecessary
              * database contention and temporary memory leaks.
              */
-            public Builder detectLeakedSqlLiteObjects() {
+            public @NonNull Builder detectLeakedSqlLiteObjects() {
                 return enable(DETECT_VM_CURSOR_LEAKS);
             }
 
@@ -892,7 +892,7 @@
              * <p>You always want to explicitly close such objects to avoid unnecessary resources
              * leaks.
              */
-            public Builder detectLeakedClosableObjects() {
+            public @NonNull Builder detectLeakedClosableObjects() {
                 return enable(DETECT_VM_CLOSABLE_LEAKS);
             }
 
@@ -900,7 +900,7 @@
              * Detect when a {@link BroadcastReceiver} or {@link ServiceConnection} is leaked during
              * {@link Context} teardown.
              */
-            public Builder detectLeakedRegistrationObjects() {
+            public @NonNull Builder detectLeakedRegistrationObjects() {
                 return enable(DETECT_VM_REGISTRATION_LEAKS);
             }
 
@@ -919,7 +919,7 @@
              * @see android.support.v4.content.FileProvider
              * @see Intent#FLAG_GRANT_READ_URI_PERMISSION
              */
-            public Builder detectFileUriExposure() {
+            public @NonNull Builder detectFileUriExposure() {
                 return enable(DETECT_VM_FILE_URI_EXPOSURE);
             }
 
@@ -938,7 +938,7 @@
              * <p>This inspects both IPv4/IPv6 and TCP/UDP network traffic, but it may be subject to
              * false positives, such as when STARTTLS protocols or HTTP proxies are used.
              */
-            public Builder detectCleartextNetwork() {
+            public @NonNull Builder detectCleartextNetwork() {
                 return enable(DETECT_VM_CLEARTEXT_NETWORK);
             }
 
@@ -954,7 +954,7 @@
              * @see Intent#FLAG_GRANT_READ_URI_PERMISSION
              * @see Intent#FLAG_GRANT_WRITE_URI_PERMISSION
              */
-            public Builder detectContentUriWithoutPermission() {
+            public @NonNull Builder detectContentUriWithoutPermission() {
                 return enable(DETECT_VM_CONTENT_URI_WITHOUT_PERMISSION);
             }
 
@@ -969,12 +969,12 @@
              * @see TrafficStats#tagSocket(java.net.Socket)
              * @see TrafficStats#tagDatagramSocket(java.net.DatagramSocket)
              */
-            public Builder detectUntaggedSockets() {
+            public @NonNull Builder detectUntaggedSockets() {
                 return enable(DETECT_VM_UNTAGGED_SOCKET);
             }
 
             /** @hide */
-            public Builder permitUntaggedSockets() {
+            public @NonNull Builder permitUntaggedSockets() {
                 return disable(DETECT_VM_UNTAGGED_SOCKET);
             }
 
@@ -992,12 +992,12 @@
              * <li>{@link PackageManager#MATCH_DIRECT_BOOT_AUTO}
              * </ul>
              */
-            public Builder detectImplicitDirectBoot() {
+            public @NonNull Builder detectImplicitDirectBoot() {
                 return enable(DETECT_VM_IMPLICIT_DIRECT_BOOT);
             }
 
             /** @hide */
-            public Builder permitImplicitDirectBoot() {
+            public @NonNull Builder permitImplicitDirectBoot() {
                 return disable(DETECT_VM_IMPLICIT_DIRECT_BOOT);
             }
 
@@ -1014,12 +1014,12 @@
              * @see Context#createCredentialProtectedStorageContext()
              * @see Context#createDeviceProtectedStorageContext()
              */
-            public Builder detectCredentialProtectedWhileLocked() {
+            public @NonNull Builder detectCredentialProtectedWhileLocked() {
                 return enable(DETECT_VM_CREDENTIAL_PROTECTED_WHILE_LOCKED);
             }
 
             /** @hide */
-            public Builder permitCredentialProtectedWhileLocked() {
+            public @NonNull Builder permitCredentialProtectedWhileLocked() {
                 return disable(DETECT_VM_CREDENTIAL_PROTECTED_WHILE_LOCKED);
             }
 
@@ -1028,7 +1028,7 @@
              * penalties so you'll still get your logging or other violations before the process
              * dies.
              */
-            public Builder penaltyDeath() {
+            public @NonNull Builder penaltyDeath() {
                 return enable(PENALTY_DEATH);
             }
 
@@ -1037,7 +1037,7 @@
              *
              * @see #detectCleartextNetwork()
              */
-            public Builder penaltyDeathOnCleartextNetwork() {
+            public @NonNull Builder penaltyDeathOnCleartextNetwork() {
                 return enable(PENALTY_DEATH_ON_CLEARTEXT_NETWORK);
             }
 
@@ -1047,12 +1047,12 @@
              *
              * @see #detectFileUriExposure()
              */
-            public Builder penaltyDeathOnFileUriExposure() {
+            public @NonNull Builder penaltyDeathOnFileUriExposure() {
                 return enable(PENALTY_DEATH_ON_FILE_URI_EXPOSURE);
             }
 
             /** Log detected violations to the system log. */
-            public Builder penaltyLog() {
+            public @NonNull Builder penaltyLog() {
                 return enable(PENALTY_LOG);
             }
 
@@ -1061,14 +1061,14 @@
              * android.os.DropBoxManager DropBox} on policy violation. Intended mostly for platform
              * integrators doing beta user field data collection.
              */
-            public Builder penaltyDropBox() {
+            public @NonNull Builder penaltyDropBox() {
                 return enable(PENALTY_DROPBOX);
             }
 
             /**
              * Call #{@link OnVmViolationListener#onVmViolation(Violation)} on every violation.
              */
-            public Builder penaltyListener(
+            public @NonNull Builder penaltyListener(
                     @NonNull Executor executor, @NonNull OnVmViolationListener listener) {
                 if (executor == null) {
                     throw new NullPointerException("executor must not be null");
@@ -1079,7 +1079,7 @@
             }
 
             /** @removed */
-            public Builder penaltyListener(
+            public @NonNull Builder penaltyListener(
                     @NonNull OnVmViolationListener listener, @NonNull Executor executor) {
                 return penaltyListener(executor, listener);
             }
diff --git a/core/java/android/provider/MediaStore.java b/core/java/android/provider/MediaStore.java
index 35c6098..a34ac70 100644
--- a/core/java/android/provider/MediaStore.java
+++ b/core/java/android/provider/MediaStore.java
@@ -3176,7 +3176,7 @@
      * {@link MediaStore.Images.Media#getContentUri(String)} to query media at
      * that location.
      */
-    public static @NonNull Set<String> getAllVolumeNames(Context context) {
+    public static @NonNull Set<String> getAllVolumeNames(@NonNull Context context) {
         final StorageManager sm = context.getSystemService(StorageManager.class);
         final Set<String> volumeNames = new ArraySet<>();
         volumeNames.add(VOLUME_INTERNAL);
@@ -3350,7 +3350,7 @@
      *         if no equivalent was found.
      * @see #getMediaUri(Context, Uri)
      */
-    public static Uri getDocumentUri(Context context, Uri mediaUri) {
+    public static @Nullable Uri getDocumentUri(@NonNull Context context, @NonNull Uri mediaUri) {
         final ContentResolver resolver = context.getContentResolver();
         final List<UriPermission> uriPermissions = resolver.getPersistedUriPermissions();
 
@@ -3380,7 +3380,7 @@
      *         equivalent was found.
      * @see #getDocumentUri(Context, Uri)
      */
-    public static Uri getMediaUri(Context context, Uri documentUri) {
+    public static @Nullable Uri getMediaUri(@NonNull Context context, @NonNull Uri documentUri) {
         final ContentResolver resolver = context.getContentResolver();
         final List<UriPermission> uriPermissions = resolver.getPersistedUriPermissions();