[2/2] Use static singleton AudioManagerRouteController

This change makes the output audio routing HSUM compatible.

Design doc: go/mr2-hsum-compatible

Change-Id: Ib9c3b72d4b333e9e2e057fa4257d21945fb3ecd8
Bug: b/372868909
Test: locally
Flag: com.android.media.flags.enable_use_of_singleton_audio_manager_route_controller

3 files changed, 59 insertions, 13 deletions

diff --git a/services/core/java/com/android/server/media/AudioManagerRouteController.java b/services/core/java/com/android/server/media/AudioManagerRouteController.java
index 280d051be239..14f870bd4e87 100644
--- a/services/core/java/com/android/server/media/AudioManagerRouteController.java
+++ b/services/core/java/com/android/server/media/AudioManagerRouteController.java
@@ -117,6 +117,35 @@ import java.util.concurrent.CopyOnWriteArrayList;
     @NonNull
     private MediaRoute2Info mSelectedRoute;
 
+    // A singleton AudioManagerRouteController.
+    private static AudioManagerRouteController mInstance;
+
+    // A flag indicating if the start function has been called.
+    private boolean mStarted = false;
+
+    // Get the singleton AudioManagerRouteController. Create a new one if it's not available yet.
+    public static AudioManagerRouteController getInstance(
+            @NonNull Context context,
+            @NonNull AudioManager audioManager,
+            @NonNull Looper looper,
+            @NonNull AudioProductStrategy strategyForMedia,
+            @NonNull BluetoothAdapter btAdapter) {
+        if (!com.android.media.flags.Flags.enableUseOfSingletonAudioManagerRouteController()) {
+            return new AudioManagerRouteController(
+                    context, audioManager, looper, strategyForMedia, btAdapter);
+        }
+
+        synchronized (AudioManagerRouteController.class) {
+            if (mInstance == null) {
+                mInstance =
+                        new AudioManagerRouteController(
+                                context, audioManager, looper, strategyForMedia, btAdapter);
+            }
+
+            return mInstance;
+        }
+    }
+
     // TODO: b/305199571 - Support nullable btAdapter and strategyForMedia which, when null, means
     // no support for transferring to inactive bluetooth routes and transferring to any routes
     // respectively.
@@ -130,13 +159,11 @@ import java.util.concurrent.CopyOnWriteArrayList;
             @NonNull AudioManager audioManager,
             @NonNull Looper looper,
             @NonNull AudioProductStrategy strategyForMedia,
-            @NonNull BluetoothAdapter btAdapter,
-            @NonNull OnDeviceRouteChangedListener onDeviceRouteChangedListener) {
+            @NonNull BluetoothAdapter btAdapter) {
         mContext = Objects.requireNonNull(context);
         mAudioManager = Objects.requireNonNull(audioManager);
         mHandler = new Handler(Objects.requireNonNull(looper));
         mStrategyForMedia = Objects.requireNonNull(strategyForMedia);
-        mOnDeviceRouteChangedListeners.add(Objects.requireNonNull(onDeviceRouteChangedListener));
 
         mBuiltInSpeakerSuitabilityStatus =
                 DeviceRouteController.getBuiltInSpeakerSuitabilityStatus(mContext);
@@ -154,6 +181,11 @@ import java.util.concurrent.CopyOnWriteArrayList;
         mOnDeviceRouteChangedListeners.add(onDeviceRouteChangedListener);
     }
 
+    public void unregisterRouteChangeListener(
+            @NonNull OnDeviceRouteChangedListener onDeviceRouteChangedListener) {
+        mOnDeviceRouteChangedListeners.remove(onDeviceRouteChangedListener);
+    }
+
     @RequiresPermission(
             anyOf = {
                 Manifest.permission.MODIFY_AUDIO_ROUTING,
@@ -161,7 +193,18 @@ import java.util.concurrent.CopyOnWriteArrayList;
             })
     @Override
     public void start(UserHandle mUser) {
-        mBluetoothRouteController.start(mUser);
+        // When AudioManagerRouteController is singleton, only need to call this function once.
+        if (com.android.media.flags.Flags.enableUseOfSingletonAudioManagerRouteController()) {
+            if (mStarted) {
+                return;
+            }
+            mStarted = true;
+        }
+
+        mBluetoothRouteController.start(
+                com.android.media.flags.Flags.enableUseOfSingletonAudioManagerRouteController()
+                        ? UserHandle.SYSTEM
+                        : mUser);
         mAudioManager.registerAudioDeviceCallback(mAudioDeviceCallback, mHandler);
         mAudioManager.addOnDevicesForAttributesChangedListener(
                 AudioRoutingUtils.ATTRIBUTES_MEDIA,
@@ -176,6 +219,11 @@ import java.util.concurrent.CopyOnWriteArrayList;
             })
     @Override
     public void stop() {
+        // Singleton AudioManagerRouteController doesn't need to call stop function.
+        if (com.android.media.flags.Flags.enableUseOfSingletonAudioManagerRouteController()) {
+            return;
+        }
+
         mAudioManager.removeOnDevicesForAttributesChangedListener(
                 mOnDevicesForAttributesChangedListener);
         mAudioManager.unregisterAudioDeviceCallback(mAudioDeviceCallback);
diff --git a/services/core/java/com/android/server/media/DeviceRouteController.java b/services/core/java/com/android/server/media/DeviceRouteController.java
index dff0adfca370..0a4cbcd1ea31 100644
--- a/services/core/java/com/android/server/media/DeviceRouteController.java
+++ b/services/core/java/com/android/server/media/DeviceRouteController.java
@@ -65,13 +65,11 @@ import java.util.List;
         if (strategyForMedia != null
                 && btAdapter != null
                 && Flags.enableAudioPoliciesDeviceAndBluetoothController()) {
-            return new AudioManagerRouteController(
-                    context,
-                    audioManager,
-                    looper,
-                    strategyForMedia,
-                    btAdapter,
-                    onDeviceRouteChangedListener);
+            AudioManagerRouteController controller =
+                    AudioManagerRouteController.getInstance(
+                            context, audioManager, looper, strategyForMedia, btAdapter);
+            controller.registerRouteChangeListener(onDeviceRouteChangedListener);
+            return controller;
         } else {
             IAudioService audioService =
                     IAudioService.Stub.asInterface(
diff --git a/services/tests/media/mediarouterservicetest/src/com/android/server/media/AudioManagerRouteControllerTest.java b/services/tests/media/mediarouterservicetest/src/com/android/server/media/AudioManagerRouteControllerTest.java
index 439243e85e75..6e9a28f344e3 100644
--- a/services/tests/media/mediarouterservicetest/src/com/android/server/media/AudioManagerRouteControllerTest.java
+++ b/services/tests/media/mediarouterservicetest/src/com/android/server/media/AudioManagerRouteControllerTest.java
@@ -139,8 +139,8 @@ public class AudioManagerRouteControllerTest {
                         mMockAudioManager,
                         Looper.getMainLooper(),
                         mMediaAudioProductStrategy,
-                        btAdapter,
-                        mOnDeviceRouteChangedListener);
+                        btAdapter);
+        mControllerUnderTest.registerRouteChangeListener(mOnDeviceRouteChangedListener);
         mControllerUnderTest.start(UserHandle.CURRENT_OR_SELF);
 
         ArgumentCaptor<AudioDeviceCallback> deviceCallbackCaptor =