diff --git a/boot/preloaded-classes b/boot/preloaded-classes
index d2eb4ce2..21ae134 100644
--- a/boot/preloaded-classes
+++ b/boot/preloaded-classes
@@ -211,7 +211,7 @@
 android.app.ActivityManager$RunningTaskInfo
 android.app.ActivityManager$TaskDescription$1
 android.app.ActivityManager$TaskDescription
-android.app.ActivityManager$UidObserver
+android.app.ActivityManager$MyUidObserver
 android.app.ActivityManager
 android.app.ActivityManagerInternal
 android.app.ActivityOptions$1
diff --git a/config/preloaded-classes b/config/preloaded-classes
index 5e2c021..8e50fe8 100644
--- a/config/preloaded-classes
+++ b/config/preloaded-classes
@@ -211,7 +211,7 @@
 android.app.ActivityManager$RunningTaskInfo
 android.app.ActivityManager$TaskDescription$1
 android.app.ActivityManager$TaskDescription
-android.app.ActivityManager$UidObserver
+android.app.ActivityManager$MyUidObserver
 android.app.ActivityManager
 android.app.ActivityManagerInternal
 android.app.ActivityOptions$1
diff --git a/core/java/android/app/ActivityManager.java b/core/java/android/app/ActivityManager.java
index 813e32a..521bf05 100644
--- a/core/java/android/app/ActivityManager.java
+++ b/core/java/android/app/ActivityManager.java
@@ -193,11 +193,11 @@
      */
     public static final int INSTR_FLAG_INSTRUMENT_SDK_SANDBOX = 1 << 5;
 
-    static final class UidObserver extends IUidObserver.Stub {
+    static final class MyUidObserver extends UidObserver {
         final OnUidImportanceListener mListener;
         final Context mContext;
 
-        UidObserver(OnUidImportanceListener listener, Context clientContext) {
+        MyUidObserver(OnUidImportanceListener listener, Context clientContext) {
             mListener = listener;
             mContext = clientContext;
         }
@@ -212,23 +212,9 @@
         public void onUidGone(int uid, boolean disabled) {
             mListener.onUidImportance(uid, RunningAppProcessInfo.IMPORTANCE_GONE);
         }
-
-        @Override
-        public void onUidActive(int uid) {
-        }
-
-        @Override
-        public void onUidIdle(int uid, boolean disabled) {
-        }
-
-        @Override public void onUidCachedChanged(int uid, boolean cached) {
-        }
-
-        @Override public void onUidProcAdjChanged(int uid) {
-        }
     }
 
-    final ArrayMap<OnUidImportanceListener, UidObserver> mImportanceListeners = new ArrayMap<>();
+    final ArrayMap<OnUidImportanceListener, MyUidObserver> mImportanceListeners = new ArrayMap<>();
 
     /**
      * Map of callbacks that have registered for {@link UidFrozenStateChanged} events.
@@ -4273,7 +4259,7 @@
                 throw new IllegalArgumentException("Listener already registered: " + listener);
             }
             // TODO: implement the cut point in the system process to avoid IPCs.
-            UidObserver observer = new UidObserver(listener, mContext);
+            MyUidObserver observer = new MyUidObserver(listener, mContext);
             try {
                 getService().registerUidObserver(observer,
                         UID_OBSERVER_PROCSTATE | UID_OBSERVER_GONE,
@@ -4297,7 +4283,7 @@
     @RequiresPermission(Manifest.permission.PACKAGE_USAGE_STATS)
     public void removeOnUidImportanceListener(OnUidImportanceListener listener) {
         synchronized (this) {
-            UidObserver observer = mImportanceListeners.remove(listener);
+            MyUidObserver observer = mImportanceListeners.remove(listener);
             if (observer == null) {
                 throw new IllegalArgumentException("Listener not registered: " + listener);
             }
diff --git a/services/core/java/com/android/server/am/AppRestrictionController.java b/services/core/java/com/android/server/am/AppRestrictionController.java
index 6928bd3..37b776d 100644
--- a/services/core/java/com/android/server/am/AppRestrictionController.java
+++ b/services/core/java/com/android/server/am/AppRestrictionController.java
@@ -101,6 +101,7 @@
 import android.app.Notification;
 import android.app.NotificationManager;
 import android.app.PendingIntent;
+import android.app.UidObserver;
 import android.app.role.OnRoleHoldersChangedListener;
 import android.app.role.RoleManager;
 import android.app.usage.AppStandbyInfo;
@@ -1439,7 +1440,7 @@
             };
 
     private final IUidObserver mUidObserver =
-            new IUidObserver.Stub() {
+            new UidObserver() {
                 @Override
                 public void onUidStateChanged(int uid, int procState, long procStateSeq,
                         int capability) {
@@ -1463,14 +1464,6 @@
                 public void onUidActive(int uid) {
                     mBgHandler.obtainMessage(BgHandler.MSG_UID_ACTIVE, uid, 0).sendToTarget();
                 }
-
-                @Override
-                public void onUidCachedChanged(int uid, boolean cached) {
-                }
-
-                @Override
-                public void onUidProcAdjChanged(int uid) {
-                }
             };
 
     /**
diff --git a/services/core/java/com/android/server/am/ProcessList.java b/services/core/java/com/android/server/am/ProcessList.java
index b26a170..b1322ef 100644
--- a/services/core/java/com/android/server/am/ProcessList.java
+++ b/services/core/java/com/android/server/am/ProcessList.java
@@ -70,7 +70,7 @@
 import android.app.ApplicationExitInfo.SubReason;
 import android.app.IApplicationThread;
 import android.app.IProcessObserver;
-import android.app.IUidObserver;
+import android.app.UidObserver;
 import android.compat.annotation.ChangeId;
 import android.compat.annotation.EnabledAfter;
 import android.content.BroadcastReceiver;
@@ -5281,7 +5281,7 @@
         return new Pair<>(numForegroundServices, procs);
     }
 
-    private final class ImperceptibleKillRunner extends IUidObserver.Stub {
+    private final class ImperceptibleKillRunner extends UidObserver {
         private static final String EXTRA_PID = "pid";
         private static final String EXTRA_UID = "uid";
         private static final String EXTRA_TIMESTAMP = "timestamp";
@@ -5537,24 +5537,8 @@
         }
 
         @Override
-        public void onUidActive(int uid) {
-        }
-
-        @Override
-        public void onUidIdle(int uid, boolean disabled) {
-        }
-
-        @Override
         public void onUidStateChanged(int uid, int procState, long procStateSeq, int capability) {
             mHandler.obtainMessage(H.MSG_UID_STATE_CHANGED, uid, procState).sendToTarget();
         }
-
-        @Override
-        public void onUidCachedChanged(int uid, boolean cached) {
-        }
-
-        @Override
-        public void onUidProcAdjChanged(int uid) {
-        }
     };
 }