diff --git a/services/core/java/com/android/server/NetworkManagementService.java b/services/core/java/com/android/server/NetworkManagementService.java
index 7e1a1ca60826e..ac2f4d09a5bae 100644
--- a/services/core/java/com/android/server/NetworkManagementService.java
+++ b/services/core/java/com/android/server/NetworkManagementService.java
@@ -149,7 +149,7 @@ public class NetworkManagementService extends INetworkManagementService.Stub
      */
     public static final String PERMISSION_SYSTEM = "SYSTEM";
 
-    class NetdResponseCode {
+    static class NetdResponseCode {
         /* Keep in sync with system/netd/server/ResponseCode.h */
         public static final int InterfaceListResult       = 110;
         public static final int TetherInterfaceListResult = 111;
@@ -220,7 +220,7 @@ public class NetworkManagementService extends INetworkManagementService.Stub
 
     private final NetworkStatsFactory mStatsFactory = new NetworkStatsFactory();
 
-    private Object mQuotaLock = new Object();
+    private final Object mQuotaLock = new Object();
 
     /** Set of interfaces with active quotas. */
     @GuardedBy("mQuotaLock")
@@ -265,7 +265,7 @@ public class NetworkManagementService extends INetworkManagementService.Stub
     @GuardedBy("mQuotaLock")
     private boolean mDataSaverMode;
 
-    private Object mIdleTimerLock = new Object();
+    private final Object mIdleTimerLock = new Object();
     /** Set of interfaces with active idle timers. */
     private static class IdleTimerParams {
         public final int timeout;