Initialize mCallback in constructor and make it final.

Test: atest frameworks/base/services/tests/servicestests/src/com/android/server/timedetector/

Change-Id: I62868ad42ec0affe6ca46e5324c5d537239337e8

services/core/java/com/android/server/timedetector/TimeDetectorService.java

@@ -64,9 +64,8 @@ public final class TimeDetectorService extends ITimeDetectorService.Stub {
     @NonNull private final TimeDetectorStrategy mTimeDetectorStrategy;
 
     private static TimeDetectorService create(@NonNull Context context) {
-        TimeDetectorStrategy timeDetectorStrategy = new TimeDetectorStrategyImpl();
-        TimeDetectorStrategyCallbackImpl callback = new TimeDetectorStrategyCallbackImpl(context);
-        timeDetectorStrategy.initialize(callback);
+        TimeDetectorStrategyImpl.Callback callback = new TimeDetectorStrategyCallbackImpl(context);
+        TimeDetectorStrategy timeDetectorStrategy = new TimeDetectorStrategyImpl(callback);
 
         Handler handler = FgThread.getHandler();
         TimeDetectorService timeDetectorService =

services/core/java/com/android/server/timedetector/TimeDetectorStrategy.java

@@ -37,46 +37,6 @@ import java.io.PrintWriter;
  */
 public interface TimeDetectorStrategy {
 
-    /**
-     * The interface used by the strategy to interact with the surrounding service.
-     *
-     * <p>Note: Because the system properties-derived value {@link #isAutoTimeDetectionEnabled()}
-     * can be modified independently and from different threads (and processes!). its use is prone
-     * to race conditions. That will be true until the responsibility for setting their values is
-     * moved to {@link TimeDetectorStrategy}. There are similar issues with
-     * {@link #systemClockMillis()} while any process can modify the system clock.
-     */
-    interface Callback {
-
-        /**
-         * The absolute threshold below which the system clock need not be updated. i.e. if setting
-         * the system clock would adjust it by less than this (either backwards or forwards) then it
-         * need not be set.
-         */
-        int systemClockUpdateThresholdMillis();
-
-        /** Returns true if automatic time detection is enabled. */
-        boolean isAutoTimeDetectionEnabled();
-
-        /** Acquire a suitable wake lock. Must be followed by {@link #releaseWakeLock()} */
-        void acquireWakeLock();
-
-        /** Returns the elapsedRealtimeMillis clock value. */
-        long elapsedRealtimeMillis();
-
-        /** Returns the system clock value. */
-        long systemClockMillis();
-
-        /** Sets the device system clock. The WakeLock must be held. */
-        void setSystemClock(long newTimeMillis);
-
-        /** Release the wake lock acquired by a call to {@link #acquireWakeLock()}. */
-        void releaseWakeLock();
-    }
-
-    /** Initialize the strategy. */
-    void initialize(@NonNull Callback callback);
-
     /** Process the suggested time from telephony sources. */
     void suggestTelephonyTime(@NonNull TelephonyTimeSuggestion timeSuggestion);
 

services/core/java/com/android/server/timedetector/TimeDetectorStrategyCallbackImpl.java

@@ -29,9 +29,9 @@ import android.util.Slog;
 import java.util.Objects;
 
 /**
- * The real implementation of {@link TimeDetectorStrategy.Callback} used on device.
+ * The real implementation of {@link TimeDetectorStrategyImpl.Callback} used on device.
  */
-public final class TimeDetectorStrategyCallbackImpl implements TimeDetectorStrategy.Callback {
+public final class TimeDetectorStrategyCallbackImpl implements TimeDetectorStrategyImpl.Callback {
 
     private final static String TAG = "timedetector.TimeDetectorStrategyCallbackImpl";
 

services/core/java/com/android/server/timedetector/TimeDetectorStrategyImpl.java

@@ -99,8 +99,8 @@ public final class TimeDetectorStrategyImpl implements TimeDetectorStrategy {
     @NonNull
     private final LocalLog mTimeChangesLog = new LocalLog(30, false /* useLocalTimestamps */);
 
-    // @NonNull after initialize()
-    private Callback mCallback;
+    @NonNull
+    private final Callback mCallback;
 
     // Used to store the last time the system clock state was set automatically. It is used to
     // detect (and log) issues with the realtime clock or whether the clock is being set without
@@ -122,8 +122,44 @@ public final class TimeDetectorStrategyImpl implements TimeDetectorStrategy {
     private final ReferenceWithHistory<NetworkTimeSuggestion> mLastNetworkSuggestion =
             new ReferenceWithHistory<>(KEEP_SUGGESTION_HISTORY_SIZE);
 
-    @Override
-    public void initialize(@NonNull Callback callback) {
+    /**
+     * The interface used by the strategy to interact with the surrounding service.
+     *
+     * <p>Note: Because the system properties-derived value {@link #isAutoTimeDetectionEnabled()}
+     * can be modified independently and from different threads (and processes!), its use is prone
+     * to race conditions. That will be true until the responsibility for setting their values is
+     * moved to {@link TimeDetectorStrategy}. There are similar issues with
+     * {@link #systemClockMillis()} while any process can modify the system clock.
+     */
+    public interface Callback {
+
+        /**
+         * The absolute threshold below which the system clock need not be updated. i.e. if setting
+         * the system clock would adjust it by less than this (either backwards or forwards) then it
+         * need not be set.
+         */
+        int systemClockUpdateThresholdMillis();
+
+        /** Returns true if automatic time detection is enabled. */
+        boolean isAutoTimeDetectionEnabled();
+
+        /** Acquire a suitable wake lock. Must be followed by {@link #releaseWakeLock()} */
+        void acquireWakeLock();
+
+        /** Returns the elapsedRealtimeMillis clock value. */
+        long elapsedRealtimeMillis();
+
+        /** Returns the system clock value. */
+        long systemClockMillis();
+
+        /** Sets the device system clock. The WakeLock must be held. */
+        void setSystemClock(long newTimeMillis);
+
+        /** Release the wake lock acquired by a call to {@link #acquireWakeLock()}. */
+        void releaseWakeLock();
+    }
+
+    TimeDetectorStrategyImpl(@NonNull Callback callback) {
         mCallback = callback;
     }
 

services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorServiceTest.java

@@ -226,10 +226,6 @@ public class TimeDetectorServiceTest {
         private boolean mHandleAutoTimeDetectionChangedCalled;
         private boolean mDumpCalled;
 
-        @Override
-        public void initialize(Callback ignored) {
-        }
-
         @Override
         public void suggestTelephonyTime(TelephonyTimeSuggestion timeSuggestion) {
             mLastTelephonySuggestion = timeSuggestion;

services/tests/servicestests/src/com/android/server/timedetector/TimeDetectorStrategyImplTest.java

@@ -616,7 +616,7 @@ public class TimeDetectorStrategyImplTest {
      * A fake implementation of TimeDetectorStrategy.Callback. Besides tracking changes and behaving
      * like the real thing should, it also asserts preconditions.
      */
-    private static class FakeCallback implements TimeDetectorStrategy.Callback {
+    private static class FakeCallback implements TimeDetectorStrategyImpl.Callback {
         private boolean mAutoTimeDetectionEnabled;
         private boolean mWakeLockAcquired;
         private long mElapsedRealtimeMillis;
@@ -731,9 +731,7 @@ public class TimeDetectorStrategyImplTest {
 
         Script() {
             mFakeCallback = new FakeCallback();
-            mTimeDetectorStrategy = new TimeDetectorStrategyImpl();
-            mTimeDetectorStrategy.initialize(mFakeCallback);
-
+            mTimeDetectorStrategy = new TimeDetectorStrategyImpl(mFakeCallback);
         }
 
         Script pokeAutoTimeDetectionEnabled(boolean enabled) {