diff --git a/src/com/android/settings/core/BasePreferenceController.java b/src/com/android/settings/core/BasePreferenceController.java
index 156b0620566..7acf95c8deb 100644
--- a/src/com/android/settings/core/BasePreferenceController.java
+++ b/src/com/android/settings/core/BasePreferenceController.java
@@ -120,7 +120,9 @@ public abstract class BasePreferenceController extends AbstractPreferenceControl
      */
     public static final int DISABLED_DEPENDENT_SETTING = 5;
 
+    @NonNull
     protected final String mPreferenceKey;
+    @Nullable
     protected UiBlockListener mUiBlockListener;
     protected boolean mUiBlockerFinished;
     private boolean mIsForWork;