Merge changes from topic "session2-pi-listcallback" into pi-dev

* changes:
  MediaSession2: Pass player info for the callbacks from MediaPlayerBase
  MediaSession2: Add MediaPlaylistController.PlaylistEventCallback

5 files changed, 705 insertions, 192 deletions

diff --git a/api/current.txt b/api/current.txt
index 307fc4bfcb37..7fe87e4365f0 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -23363,10 +23363,12 @@ package android.media {
     method public float getPlaybackSpeed();
     method public int getPlayerState();
     method public java.util.List<android.media.MediaItem2> getPlaylist();
-    method public android.media.MediaSession2.PlaylistParams getPlaylistParams();
+    method public android.media.MediaMetadata2 getPlaylistMetadata();
     method public long getPosition();
+    method public int getRepeatMode();
     method public android.app.PendingIntent getSessionActivity();
     method public android.media.SessionToken2 getSessionToken();
+    method public int getShuffleMode();
     method public boolean isConnected();
     method public void pause();
     method public void play();
@@ -23377,19 +23379,24 @@ package android.media {
     method public void prepareFromMediaId(java.lang.String, android.os.Bundle);
     method public void prepareFromSearch(java.lang.String, android.os.Bundle);
     method public void prepareFromUri(android.net.Uri, android.os.Bundle);
+    method public void registerPlaylistControllerCallback(java.util.concurrent.Executor, android.media.MediaPlaylistController.PlaylistEventCallback);
     method public void removePlaylistItem(android.media.MediaItem2);
     method public void replacePlaylistItem(int, android.media.MediaItem2);
     method public void rewind();
     method public void seekTo(long);
     method public void sendCustomCommand(android.media.MediaSession2.Command, android.os.Bundle, android.os.ResultReceiver);
     method public void setPlaybackSpeed(float);
-    method public void setPlaylistParams(android.media.MediaSession2.PlaylistParams);
+    method public void setPlaylist(java.util.List<android.media.MediaItem2>, android.media.MediaMetadata2);
     method public void setRating(java.lang.String, android.media.Rating2);
+    method public void setRepeatMode(int);
+    method public void setShuffleMode(int);
     method public void setVolumeTo(int, int);
     method public void skipToNext();
     method public void skipToPlaylistItem(android.media.MediaItem2);
     method public void skipToPrevious();
     method public void stop();
+    method public void unregisterPlaylistControllerCallback(android.media.MediaPlaylistController.PlaylistEventCallback);
+    method public void updatePlaylistMetadata(android.media.MediaMetadata2);
   }
 
   public static abstract class MediaController2.ControllerCallback {
@@ -23405,8 +23412,6 @@ package android.media {
     method public void onPlaybackInfoChanged(android.media.MediaController2, android.media.MediaController2.PlaybackInfo);
     method public void onPlaybackSpeedChanged(android.media.MediaController2, float);
     method public void onPlayerStateChanged(android.media.MediaController2, int);
-    method public void onPlaylistChanged(android.media.MediaController2, java.util.List<android.media.MediaItem2>);
-    method public void onPlaylistParamsChanged(android.media.MediaController2, android.media.MediaSession2.PlaylistParams);
     method public void onPositionChanged(android.media.MediaController2, long, long);
   }
 
@@ -24541,9 +24546,33 @@ package android.media {
     method public abstract void addPlaylistItem(int, android.media.MediaItem2);
     method public abstract android.media.MediaItem2 getCurrentPlaylistItem();
     method public abstract java.util.List<android.media.MediaItem2> getPlaylist();
+    method public abstract android.media.MediaMetadata2 getPlaylistMetadata();
+    method public abstract int getRepeatMode();
+    method public abstract int getShuffleMode();
+    method public abstract void registerPlaylistControllerCallback(java.util.concurrent.Executor, android.media.MediaPlaylistController.PlaylistEventCallback);
     method public abstract void removePlaylistItem(android.media.MediaItem2);
     method public abstract void replacePlaylistItem(int, android.media.MediaItem2);
+    method public abstract void setPlaylist(java.util.List<android.media.MediaItem2>, android.media.MediaMetadata2);
+    method public abstract void setRepeatMode(int);
+    method public abstract void setShuffleMode(int);
     method public abstract void skipToPlaylistItem(android.media.MediaItem2);
+    method public abstract void unregisterPlaylistControllerCallback(android.media.MediaPlaylistController.PlaylistEventCallback);
+    method public abstract void updatePlaylistMetadata(android.media.MediaMetadata2);
+    field public static final int REPEAT_MODE_ALL = 2; // 0x2
+    field public static final int REPEAT_MODE_GROUP = 3; // 0x3
+    field public static final int REPEAT_MODE_NONE = 0; // 0x0
+    field public static final int REPEAT_MODE_ONE = 1; // 0x1
+    field public static final int SHUFFLE_MODE_ALL = 1; // 0x1
+    field public static final int SHUFFLE_MODE_GROUP = 2; // 0x2
+    field public static final int SHUFFLE_MODE_NONE = 0; // 0x0
+  }
+
+  public static abstract class MediaPlaylistController.PlaylistEventCallback {
+    ctor public MediaPlaylistController.PlaylistEventCallback();
+    method public void onPlaylistChanged(android.media.MediaPlaylistController, java.util.List<android.media.MediaItem2>, android.media.MediaMetadata2);
+    method public void onPlaylistMetadataChanged(android.media.MediaPlaylistController, android.media.MediaMetadata2);
+    method public void onRepeatModeChanged(android.media.MediaPlaylistController, int);
+    method public void onShuffleModeChanged(android.media.MediaPlaylistController, int);
   }
 
   public class MediaRecorder implements android.media.AudioRouting {
@@ -24832,13 +24861,16 @@ package android.media {
     method public float getPlaybackSpeed();
     method public android.media.MediaPlayerBase getPlayer();
     method public java.util.List<android.media.MediaItem2> getPlaylist();
-    method public android.media.MediaSession2.PlaylistParams getPlaylistParams();
+    method public android.media.MediaMetadata2 getPlaylistMetadata();
+    method public int getRepeatMode();
+    method public int getShuffleMode();
     method public android.media.SessionToken2 getToken();
     method public android.media.VolumeProvider2 getVolumeProvider();
     method public void notifyError(int, android.os.Bundle);
     method public void pause();
     method public void play();
     method public void prepare();
+    method public void registerPlaylistControllerCallback(java.util.concurrent.Executor, android.media.MediaPlaylistController.PlaylistEventCallback);
     method public void removePlaylistItem(android.media.MediaItem2);
     method public void replacePlaylistItem(int, android.media.MediaItem2);
     method public void rewind();
@@ -24849,36 +24881,45 @@ package android.media {
     method public void setAudioFocusRequest(android.media.AudioFocusRequest);
     method public void setCustomLayout(android.media.MediaSession2.ControllerInfo, java.util.List<android.media.MediaSession2.CommandButton>);
     method public void setPlaybackSpeed(float);
-    method public void setPlaylist(java.util.List<android.media.MediaItem2>);
-    method public void setPlaylistParams(android.media.MediaSession2.PlaylistParams);
+    method public void setPlaylist(java.util.List<android.media.MediaItem2>, android.media.MediaMetadata2);
+    method public void setRepeatMode(int);
+    method public void setShuffleMode(int);
     method public void skipToNext();
     method public void skipToPlaylistItem(android.media.MediaItem2);
     method public void skipToPrevious();
     method public void stop();
+    method public void unregisterPlaylistControllerCallback(android.media.MediaPlaylistController.PlaylistEventCallback);
     method public void updatePlayer(android.media.MediaPlayerBase, android.media.MediaPlaylistController, android.media.VolumeProvider2);
-    field public static final int COMMAND_CODE_BROWSER = 22; // 0x16
+    method public void updatePlaylistMetadata(android.media.MediaMetadata2);
+    field public static final int COMMAND_CODE_BROWSER = 28; // 0x1c
     field public static final int COMMAND_CODE_CUSTOM = 0; // 0x0
+    field public static final int COMMAND_CODE_PLAYBACK_ADJUST_VOLUME = 11; // 0xb
     field public static final int COMMAND_CODE_PLAYBACK_FAST_FORWARD = 7; // 0x7
     field public static final int COMMAND_CODE_PLAYBACK_PAUSE = 2; // 0x2
     field public static final int COMMAND_CODE_PLAYBACK_PLAY = 1; // 0x1
     field public static final int COMMAND_CODE_PLAYBACK_PREPARE = 6; // 0x6
     field public static final int COMMAND_CODE_PLAYBACK_REWIND = 8; // 0x8
     field public static final int COMMAND_CODE_PLAYBACK_SEEK_TO = 9; // 0x9
-    field public static final int COMMAND_CODE_PLAYBACK_SET_PLAYLIST_PARAMS = 11; // 0xb
+    field public static final int COMMAND_CODE_PLAYBACK_SET_VOLUME = 10; // 0xa
     field public static final int COMMAND_CODE_PLAYBACK_SKIP_NEXT_ITEM = 4; // 0x4
     field public static final int COMMAND_CODE_PLAYBACK_SKIP_PREV_ITEM = 5; // 0x5
-    field public static final int COMMAND_CODE_PLAYBACK_SKIP_TO_PLAYLIST_ITEM = 10; // 0xa
     field public static final int COMMAND_CODE_PLAYBACK_STOP = 3; // 0x3
-    field public static final int COMMAND_CODE_PLAYLIST_ADD = 12; // 0xc
-    field public static final int COMMAND_CODE_PLAYLIST_GET = 14; // 0xe
-    field public static final int COMMAND_CODE_PLAYLIST_REMOVE = 13; // 0xd
-    field public static final int COMMAND_CODE_PLAY_FROM_MEDIA_ID = 16; // 0x10
-    field public static final int COMMAND_CODE_PLAY_FROM_SEARCH = 18; // 0x12
-    field public static final int COMMAND_CODE_PLAY_FROM_URI = 17; // 0x11
-    field public static final int COMMAND_CODE_PREPARE_FROM_MEDIA_ID = 19; // 0x13
-    field public static final int COMMAND_CODE_PREPARE_FROM_SEARCH = 21; // 0x15
-    field public static final int COMMAND_CODE_PREPARE_FROM_URI = 20; // 0x14
-    field public static final int COMMAND_CODE_SET_VOLUME = 15; // 0xf
+    field public static final int COMMAND_CODE_PLAYLIST_ADD_ITEM = 15; // 0xf
+    field public static final int COMMAND_CODE_PLAYLIST_GET_LIST = 18; // 0x12
+    field public static final int COMMAND_CODE_PLAYLIST_GET_LIST_METADATA = 20; // 0x14
+    field public static final int COMMAND_CODE_PLAYLIST_REMOVE_ITEM = 16; // 0x10
+    field public static final int COMMAND_CODE_PLAYLIST_REPLACE_ITEM = 17; // 0x11
+    field public static final int COMMAND_CODE_PLAYLIST_SET_LIST = 19; // 0x13
+    field public static final int COMMAND_CODE_PLAYLIST_SET_LIST_METADATA = 21; // 0x15
+    field public static final int COMMAND_CODE_PLAYLIST_SET_REPEAT_MODE = 14; // 0xe
+    field public static final int COMMAND_CODE_PLAYLIST_SET_SHUFFLE_MODE = 13; // 0xd
+    field public static final int COMMAND_CODE_PLAYLIST_SKIP_TO_PLAYLIST_ITEM = 12; // 0xc
+    field public static final int COMMAND_CODE_PLAY_FROM_MEDIA_ID = 22; // 0x16
+    field public static final int COMMAND_CODE_PLAY_FROM_SEARCH = 24; // 0x18
+    field public static final int COMMAND_CODE_PLAY_FROM_URI = 23; // 0x17
+    field public static final int COMMAND_CODE_PREPARE_FROM_MEDIA_ID = 25; // 0x19
+    field public static final int COMMAND_CODE_PREPARE_FROM_SEARCH = 27; // 0x1b
+    field public static final int COMMAND_CODE_PREPARE_FROM_URI = 26; // 0x1a
     field public static final int ERROR_CODE_ACTION_ABORTED = 10; // 0xa
     field public static final int ERROR_CODE_APP_ERROR = 1; // 0x1
     field public static final int ERROR_CODE_AUTHENTICATION_EXPIRED = 3; // 0x3
@@ -24948,31 +24989,18 @@ package android.media {
     method public boolean isTrusted();
   }
 
-  public static final class MediaSession2.PlaylistParams {
-    ctor public MediaSession2.PlaylistParams(android.content.Context, int, int, android.media.MediaMetadata2);
-    method public static android.media.MediaSession2.PlaylistParams fromBundle(android.content.Context, android.os.Bundle);
-    method public android.media.MediaMetadata2 getPlaylistMetadata();
-    method public int getRepeatMode();
-    method public int getShuffleMode();
-    method public android.os.Bundle toBundle();
-    field public static final int REPEAT_MODE_ALL = 2; // 0x2
-    field public static final int REPEAT_MODE_GROUP = 3; // 0x3
-    field public static final int REPEAT_MODE_NONE = 0; // 0x0
-    field public static final int REPEAT_MODE_ONE = 1; // 0x1
-    field public static final int SHUFFLE_MODE_ALL = 1; // 0x1
-    field public static final int SHUFFLE_MODE_GROUP = 2; // 0x2
-    field public static final int SHUFFLE_MODE_NONE = 0; // 0x0
-  }
-
   public static abstract class MediaSession2.SessionCallback {
     ctor public MediaSession2.SessionCallback(android.content.Context);
+    method public void onBufferingStateChanged(android.media.MediaSession2, android.media.MediaPlayerBase, android.media.MediaItem2, int);
     method public boolean onCommandRequest(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo, android.media.MediaSession2.Command);
     method public android.media.MediaSession2.CommandGroup onConnect(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo);
     method public void onCustomCommand(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo, android.media.MediaSession2.Command, android.os.Bundle, android.os.ResultReceiver);
     method public void onDisconnected(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo);
+    method public void onMediaPrepared(android.media.MediaSession2, android.media.MediaPlayerBase, android.media.MediaItem2);
     method public void onPlayFromMediaId(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo, java.lang.String, android.os.Bundle);
     method public void onPlayFromSearch(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo, java.lang.String, android.os.Bundle);
     method public void onPlayFromUri(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo, android.net.Uri, android.os.Bundle);
+    method public void onPlayerStateChanged(android.media.MediaSession2, android.media.MediaPlayerBase, int);
     method public void onPrepareFromMediaId(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo, java.lang.String, android.os.Bundle);
     method public void onPrepareFromSearch(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo, java.lang.String, android.os.Bundle);
     method public void onPrepareFromUri(android.media.MediaSession2, android.media.MediaSession2.ControllerInfo, android.net.Uri, android.os.Bundle);
diff --git a/media/java/android/media/MediaController2.java b/media/java/android/media/MediaController2.java
index df7b5afc83e3..25188fb1ba3c 100644
--- a/media/java/android/media/MediaController2.java
+++ b/media/java/android/media/MediaController2.java
@@ -147,7 +147,9 @@ public class MediaController2 implements AutoCloseable, MediaPlaylistController
          * @see #onPositionChanged(MediaController2, long, long)
          * @see #onBufferedPositionChanged(MediaController2, long)
          * @see #onCurrentPlaylistItemChanged(MediaController2, MediaItem2)
+         * @hide
          */
+        // TODO(jaewan): Remove (b/74174728)
         public void onPlaylistChanged(@NonNull MediaController2 controller,
                 @NonNull List<MediaItem2> playlist) { }
 
@@ -228,7 +230,9 @@ public class MediaController2 implements AutoCloseable, MediaPlaylistController
          *
          * @param controller the controller for this event
          * @param params The new play list parameters.
+         * @hide
          */
+        // TODO(jaewan): Remove (b/74116823)
         public void onPlaylistParamsChanged(@NonNull MediaController2 controller,
                 @NonNull PlaylistParams params) { }
     }
@@ -440,24 +444,14 @@ public class MediaController2 implements AutoCloseable, MediaPlaylistController
     }
 
     /**
-     * Sets the index of current DataSourceDesc in the play list to be played.
-     *
-     * @param item the index of DataSourceDesc in the play list you want to play
-     * @throws IllegalArgumentException if the play list is null
-     * @throws NullPointerException if index is outside play list range
-     */
-    @Override
-    public void skipToPlaylistItem(@NonNull MediaItem2 item) {
-        mProvider.skipToPlaylistItem_impl(item);
-    }
-
-    /**
      * Sets the {@link PlaylistParams} for the current play list. Repeat/shuffle mode and metadata
      * for the list can be set by calling this method.
      *
      * @param params A {@link PlaylistParams} object to set.
      * @throws IllegalArgumentException if given {@param param} is null.
+     * @hide
      */
+    // TODO(jaewan): Remove (b/74116823)
     public void setPlaylistParams(@NonNull PlaylistParams params) {
         mProvider.setPlaylistParams_impl(params);
     }
@@ -672,17 +666,6 @@ public class MediaController2 implements AutoCloseable, MediaPlaylistController
     }
 
     /**
-     * Get the lastly cached current item from
-     * {@link ControllerCallback#onCurrentPlaylistItemChanged(MediaController2, MediaItem2)}.
-     *
-     * @return index of the current item
-     */
-    @Override
-    public MediaItem2 getCurrentPlaylistItem() {
-        return mProvider.getCurrentPlaylistItem_impl();
-    }
-
-    /**
      * Get the current playback info for this session.
      *
      * @return The current playback info or null.
@@ -720,6 +703,35 @@ public class MediaController2 implements AutoCloseable, MediaPlaylistController
     }
 
     /**
+     * Register {@link MediaPlaylistController.PlaylistEventCallback} to listen changes in the
+     * underlying {@link MediaPlaylistController}, regardless of the change in the controller.
+     * <p>
+     * Registered callbacks will be also called when the controller is changed.
+     *
+     * @param executor a callback Executor
+     * @param callback a PlaylistEventCallback
+     * @throws IllegalArgumentException if executor or callback is {@code null}.
+     */
+    @Override
+    public void registerPlaylistControllerCallback(@NonNull @CallbackExecutor Executor executor,
+            @NonNull PlaylistEventCallback callback) {
+        // TODO(jaewan): Implement (b/74169681)
+        //mProvider.registerPlaylistControllerCallback_impl(executor, callback);
+    }
+
+    /**
+     * Unregister the previously registered {@link MediaPlaylistController.PlaylistEventCallback}.
+     *
+     * @param callback the callback to be removed
+     * @throws IllegalArgumentException if the callback is {@code null}.
+     */
+    @Override
+    public void unregisterPlaylistControllerCallback(@NonNull PlaylistEventCallback callback) {
+        // TODO(jaewan): Implement (b/74169681)
+        //mProvider.unregisterPlaylistControllerCallback_impl(callback);
+    }
+
+    /**
      * Return playlist from the session.
      *
      * @return playlist. Can be {@code null} if the controller doesn't have enough permission.
@@ -729,16 +741,51 @@ public class MediaController2 implements AutoCloseable, MediaPlaylistController
         return mProvider.getPlaylist_impl();
     }
 
+
+    @Override
+    public void setPlaylist(@NonNull List<MediaItem2> list, @Nullable MediaMetadata2 metadata) {
+        // TODO(jaewan): Implement (b/74174649)
+    }
+
+    @Override
+    public void updatePlaylistMetadata(@Nullable MediaMetadata2 metadata) {
+        // TODO(jaewan): Implement (b/74174649)
+    }
+
+    @Override
+    public @Nullable MediaMetadata2 getPlaylistMetadata() {
+        // TODO(jaewan): Implement (b/74174649)
+        return null;
+    }
+
     /**
      * Returns the {@link PlaylistParams} for the current play list.
      * Can return {@code null} if the controller doesn't have enough permission, or if the session
      * has not set the parameters.
+     * @hide
      */
+    // TODO(jaewan): Remove (b/74116823)
     public @Nullable PlaylistParams getPlaylistParams() {
         return mProvider.getPlaylistParams_impl();
     }
 
     /**
+     * Inserts the media item to the play list at position index.
+     * <p>
+     * This will not change the currently playing media item.
+     * If index is less than or equal to the current index of the play list,
+     * the current index of the play list will be incremented correspondingly.
+     *
+     * @param index the index you want to add
+     * @param item the media item you want to add
+     * @throws IndexOutOfBoundsException if index is outside play list range
+     */
+    @Override
+    public void addPlaylistItem(int index, @NonNull MediaItem2 item) {
+        mProvider.addPlaylistItem_impl(index, item);
+    }
+
+    /**
      * Removes the media item at index in the playlist.
      *<p>
      * If the item is the currently playing item of the playlist, current playback
@@ -760,18 +807,47 @@ public class MediaController2 implements AutoCloseable, MediaPlaylistController
     }
 
     /**
-     * Inserts the media item to the play list at position index.
-     * <p>
-     * This will not change the currently playing media item.
-     * If index is less than or equal to the current index of the play list,
-     * the current index of the play list will be incremented correspondingly.
+     * Get the lastly cached current item from
+     * {@link ControllerCallback#onCurrentPlaylistItemChanged(MediaController2, MediaItem2)}.
      *
-     * @param index the index you want to add
-     * @param item the media item you want to add
-     * @throws IndexOutOfBoundsException if index is outside play list range
+     * @return index of the current item
      */
     @Override
-    public void addPlaylistItem(int index, @NonNull MediaItem2 item) {
-        mProvider.addPlaylistItem_impl(index, item);
+    public MediaItem2 getCurrentPlaylistItem() {
+        return mProvider.getCurrentPlaylistItem_impl();
+    }
+
+    /**
+     * Sets the index of current DataSourceDesc in the play list to be played.
+     *
+     * @param item the index of DataSourceDesc in the play list you want to play
+     * @throws IllegalArgumentException if the play list is null
+     * @throws NullPointerException if index is outside play list range
+     */
+    @Override
+    public void skipToPlaylistItem(@NonNull MediaItem2 item) {
+        mProvider.skipToPlaylistItem_impl(item);
+    }
+
+    @Override
+    public @RepeatMode int getRepeatMode() {
+        // TODO(jaewan): Implement (b/74118768)
+        return 0;
+    }
+
+    @Override
+    public void setRepeatMode(int repeatMode) {
+        // TODO(jaewan): Implement (b/74118768)
+    }
+
+    @Override
+    public @ShuffleMode int getShuffleMode() {
+        // TODO(jaewan): Implement (b/74118768)
+        return 0;
+    }
+
+    @Override
+    public void setShuffleMode(int shuffleMode) {
+        // TODO(jaewan): Implement (b/74118768)
     }
 }
diff --git a/media/java/android/media/MediaPlayerBase.java b/media/java/android/media/MediaPlayerBase.java
index 24274f1356e3..70a36bf201dd 100644
--- a/media/java/android/media/MediaPlayerBase.java
+++ b/media/java/android/media/MediaPlayerBase.java
@@ -278,7 +278,7 @@ public abstract class MediaPlayerBase implements AutoCloseable {
      */
     public static abstract class PlayerEventCallback {
         /**
-         * Called when the player's curretn data source has changed.
+         * Called when the player's current data source has changed.
          * @param mpb the player whose data source changed.
          * @param dsd the new current data source.
          */
diff --git a/media/java/android/media/MediaPlaylistController.java b/media/java/android/media/MediaPlaylistController.java
index c98d50e2c5e7..1ad56178b757 100644
--- a/media/java/android/media/MediaPlaylistController.java
+++ b/media/java/android/media/MediaPlaylistController.java
@@ -16,9 +16,18 @@
 
 package android.media;
 
+import android.annotation.CallbackExecutor;
+import android.annotation.IntDef;
 import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.media.MediaSession2.PlaylistParams;
+import android.media.MediaSession2.PlaylistParams.RepeatMode;
+import android.media.MediaSession2.PlaylistParams.ShuffleMode;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
 import java.util.List;
+import java.util.concurrent.Executor;
 
 /**
  * Controller interface for playlist management.
@@ -30,10 +39,231 @@ import java.util.List;
  // Note that setPlaylist() isn't added on purpose because it's considered session-specific.
 
 public interface MediaPlaylistController {
+    /**
+     * @hide
+     */
+    @IntDef({REPEAT_MODE_NONE, REPEAT_MODE_ONE, REPEAT_MODE_ALL,
+            REPEAT_MODE_GROUP})
+    @Retention(RetentionPolicy.SOURCE)
+    @interface RepeatMode {}
+
+    /**
+     * Playback will be stopped at the end of the playing media list.
+     */
+    int REPEAT_MODE_NONE = 0;
+
+    /**
+     * Playback of the current playing media item will be repeated.
+     */
+    int REPEAT_MODE_ONE = 1;
+
+    /**
+     * Playing media list will be repeated.
+     */
+    int REPEAT_MODE_ALL = 2;
+
+    /**
+     * Playback of the playing media group will be repeated.
+     * A group is a logical block of media items which is specified in the section 5.7 of the
+     * Bluetooth AVRCP 1.6. An example of a group is the playlist.
+     */
+    int REPEAT_MODE_GROUP = 3;
+
+    /**
+     * @hide
+     */
+    @IntDef({SHUFFLE_MODE_NONE, SHUFFLE_MODE_ALL, SHUFFLE_MODE_GROUP})
+    @Retention(RetentionPolicy.SOURCE)
+    @interface ShuffleMode {}
+
+    /**
+     * Media list will be played in order.
+     */
+    int SHUFFLE_MODE_NONE = 0;
+
+    /**
+     * Media list will be played in shuffled order.
+     */
+    int SHUFFLE_MODE_ALL = 1;
+
+    /**
+     * Media group will be played in shuffled order.
+     * A group is a logical block of media items which is specified in the section 5.7 of the
+     * Bluetooth AVRCP 1.6. An example of a group is the playlist.
+     */
+    int SHUFFLE_MODE_GROUP = 2;
+
+    abstract class PlaylistEventCallback {
+        /**
+         * Called when a playlist is changed.
+         *
+         * @param mplc playlist controller for this event
+         * @param list new playlist
+         * @param metadata new metadata
+         */
+        public void onPlaylistChanged(@NonNull MediaPlaylistController mplc,
+                @NonNull List<MediaItem2> list, @Nullable MediaMetadata2 metadata) { }
+
+        /**
+         * Called when a playlist is changed.
+         *
+         * @param mplc playlist controller for this event
+         * @param metadata new metadata
+         */
+        public void onPlaylistMetadataChanged(@NonNull MediaPlaylistController mplc,
+                @Nullable MediaMetadata2 metadata) { }
+
+        /**
+         * Called when a playlist is changed.
+         *
+         * @param mplc playlist controller for this event
+         * @param shuffleMode repeat mode
+         * @see #SHUFFLE_MODE_NONE
+         * @see #SHUFFLE_MODE_ALL
+         * @see #SHUFFLE_MODE_GROUP
+         */
+        public void onShuffleModeChanged(@NonNull MediaPlaylistController mplc,
+                @ShuffleMode int shuffleMode) { }
+
+        /**
+         * Called when a playlist is changed.
+         *
+         * @param mplc playlist controller for this event
+         * @param repeatMode repeat mode
+         * @see #REPEAT_MODE_NONE
+         * @see #REPEAT_MODE_ONE
+         * @see #REPEAT_MODE_ALL
+         * @see #REPEAT_MODE_GROUP
+         */
+        public void onRepeatModeChanged(@NonNull MediaPlaylistController mplc,
+                @RepeatMode int repeatMode) { }
+    }
+
+    /**
+     * Register {@link PlaylistEventCallback} to listen changes in the underlying
+     * {@link MediaPlaylistController}, regardless of the change in the controller.
+     *
+     * @param executor a callback Executor
+     * @param callback a PlaylistEventCallback
+     * @throws IllegalArgumentException if executor or callback is {@code null}.
+     */
+    void registerPlaylistControllerCallback(@NonNull @CallbackExecutor Executor executor,
+            @NonNull PlaylistEventCallback callback);
+
+    /**
+     * Unregister the previously registered {@link PlaylistEventCallback}.
+     *
+     * @param callback the callback to be removed
+     * @throws IllegalArgumentException if the callback is {@code null}.
+     */
+    void unregisterPlaylistControllerCallback(@NonNull PlaylistEventCallback callback);
+
+    /**
+     * Returns the playlist
+     *
+     * @return playlist, or null if none is set.
+     */
+    @Nullable List<MediaItem2> getPlaylist();
+
+    /**
+     * Sets the playlist.
+     *
+     * @param list playlist
+     * @param metadata metadata of the playlist
+     */
+    void setPlaylist(@NonNull List<MediaItem2> list, @Nullable MediaMetadata2 metadata);
+
+    /**
+     * Returns the playlist metadata
+     *
+     * @return metadata metadata of the playlist, or null if none is set
+     */
+    @Nullable MediaMetadata2 getPlaylistMetadata();
+
+    /**
+     * Updates the playlist metadata
+     *
+     * @param metadata metadata of the playlist
+     */
+    void updatePlaylistMetadata(@Nullable MediaMetadata2 metadata);
+
+    /**
+     * Adds the media item to the playlist at the index
+     *
+     * @param index index
+     * @param item media item to add
+     */
     void addPlaylistItem(int index, @NonNull MediaItem2 item);
+
+    /**
+     * Removes the media item from the playlist
+     *
+     * @param item media item to remove
+     */
     void removePlaylistItem(@NonNull MediaItem2 item);
+
+    /**
+     * Replaces the media item with the .
+     * <p>
+     * This can be used to update metadata of a MediaItem.
+     *
+     * @param index index
+     * @param item
+     */
+    void replacePlaylistItem(int index, @NonNull MediaItem2 item);
+
+    /**
+     * Returns the current media item.
+     * @return the current media item, or null if none is set, or none available to play.
+     */
     MediaItem2 getCurrentPlaylistItem();
+
+    /**
+     * Skips to the the media item, and plays from it.
+     *
+     * @param item media item to start playing from
+     */
     void skipToPlaylistItem(@NonNull MediaItem2 item);
-    void replacePlaylistItem(int index, @NonNull MediaItem2 item);
-    List<MediaItem2> getPlaylist();
+
+    /**
+     * Get repeat mode
+     *
+     * @return repeat mode
+     * @see #REPEAT_MODE_NONE
+     * @see #REPEAT_MODE_ONE
+     * @see #REPEAT_MODE_ALL
+     * @see #REPEAT_MODE_GROUP
+     */
+    @RepeatMode int getRepeatMode();
+
+    /**
+     * Set repeat mode
+     *
+     * @param repeatMode repeat mode
+     * @see #REPEAT_MODE_NONE
+     * @see #REPEAT_MODE_ONE
+     * @see #REPEAT_MODE_ALL
+     * @see #REPEAT_MODE_GROUP
+     */
+    void setRepeatMode(@RepeatMode int repeatMode);
+
+    /**
+     * Get shuffle mode
+     *
+     * @return shuffle mode
+     * @see #SHUFFLE_MODE_NONE
+     * @see #SHUFFLE_MODE_ALL
+     * @see #SHUFFLE_MODE_GROUP
+     */
+    @ShuffleMode int getShuffleMode();
+
+    /**
+     * Set shuffle mode
+     *
+     * @param shuffleMode shuffle mode
+     * @see #SHUFFLE_MODE_NONE
+     * @see #SHUFFLE_MODE_ALL
+     * @see #SHUFFLE_MODE_GROUP
+     */
+    void setShuffleMode(@ShuffleMode int shuffleMode);
 }
diff --git a/media/java/android/media/MediaSession2.java b/media/java/android/media/MediaSession2.java
index cad63e3950a1..ddb51c3e697d 100644
--- a/media/java/android/media/MediaSession2.java
+++ b/media/java/android/media/MediaSession2.java
@@ -23,7 +23,9 @@ import android.annotation.Nullable;
 import android.app.PendingIntent;
 import android.content.Context;
 import android.content.Intent;
+import android.media.MediaPlayerBase.BuffState;
 import android.media.MediaPlayerBase.PlayerEventCallback;
+import android.media.MediaPlayerBase.PlayerState;
 import android.media.session.MediaSession;
 import android.media.session.MediaSession.Callback;
 import android.media.session.PlaybackState;
@@ -81,7 +83,6 @@ import java.util.concurrent.Executor;
 public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
     private final MediaSession2Provider mProvider;
 
-    // Next ID: 23
     /**
      * Command code for the custom command which can be defined by string action in the
      * {@link Command}.
@@ -160,94 +161,173 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
      * through the {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
      */
     public static final int COMMAND_CODE_PLAYBACK_SEEK_TO = 9;
+
     /**
-     * Command code for {@link MediaController2#skipToPlaylistItem(MediaItem2)}.
+     * Command code for both {@link MediaController2#setVolumeTo(int, int)}.
      * <p>
-     * Command would be sent directly to the player if the session doesn't reject the request
-     * through the {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     * Command would set the device volume or send to the volume provider directly if the session
+     * doesn't reject the request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     */
+    public static final int COMMAND_CODE_PLAYBACK_SET_VOLUME = 10;
+
+    /**
+     * Command code for both {@link MediaController2#adjustVolume(int, int)}.
+     * <p>
+     * Command would adjust the device volume or send to the volume provider directly if the session
+     * doesn't reject the request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
      */
-    public static final int COMMAND_CODE_PLAYBACK_SKIP_TO_PLAYLIST_ITEM = 10;
+    public static final int COMMAND_CODE_PLAYBACK_ADJUST_VOLUME = 11;
 
     /**
      * Command code for {@link MediaController2#setPlaylistParams(PlaylistParams)}.
      * <p>
      * Command would be sent directly to the player if the session doesn't reject the request
      * through the {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     * @hide
      */
-    public static final int COMMAND_CODE_PLAYBACK_SET_PLAYLIST_PARAMS = 11;
+    // TODO(jaewan): Remove (b/74116823)
+    public static final int COMMAND_CODE_PLAYBACK_SET_PLAYLIST_PARAMS = 12;
+
+    /**
+     * Command code for {@link MediaController2#skipToPlaylistItem(MediaItem2)}.
+     * <p>
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     */
+    public static final int COMMAND_CODE_PLAYLIST_SKIP_TO_PLAYLIST_ITEM = 12;
+
+    /**
+     * Command code for {@link MediaController2#setShuffleMode(int)}.
+     * <p>
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     */
+    public static final int COMMAND_CODE_PLAYLIST_SET_SHUFFLE_MODE = 13;
+
+    /**
+     * Command code for {@link MediaController2#setRepeatMode(int)}.
+     * <p>
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     */
+    public static final int COMMAND_CODE_PLAYLIST_SET_REPEAT_MODE = 14;
 
     /**
      * Command code for {@link MediaController2#addPlaylistItem(int, MediaItem2)}.
      * <p>
-     * Command would be sent directly to the player if the session doesn't reject the request
-     * through the {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
      */
-    public static final int COMMAND_CODE_PLAYLIST_ADD = 12;
+    public static final int COMMAND_CODE_PLAYLIST_ADD_ITEM = 15;
 
     /**
      * Command code for {@link MediaController2#addPlaylistItem(int, MediaItem2)}.
      * <p>
-     * Command would be sent directly to the player if the session doesn't reject the request
-     * through the {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
      */
-    public static final int COMMAND_CODE_PLAYLIST_REMOVE = 13;
+    public static final int COMMAND_CODE_PLAYLIST_REMOVE_ITEM = 16;
 
     /**
-     * Command code for {@link MediaController2#getPlaylist()}.
+     * Command code for {@link MediaController2#replacePlaylistItem(int, MediaItem2)}.
      * <p>
-     * Command would be sent directly to the player if the session doesn't reject the request
-     * through the {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
      */
-    public static final int COMMAND_CODE_PLAYLIST_GET = 14;
+    public static final int COMMAND_CODE_PLAYLIST_REPLACE_ITEM = 17;
 
     /**
-     * Command code for both {@link MediaController2#setVolumeTo(int, int)} and
-     * {@link MediaController2#adjustVolume(int, int)}.
+     * Command code for {@link MediaController2#getPlaylist()}. This will expose metadata
+     * information to the controller.
      * <p>
-     * Command would adjust the volume or sent to the volume provider directly if the session
-     * doesn't reject the request through the
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     */
+    public static final int COMMAND_CODE_PLAYLIST_GET_LIST = 18;
+
+    /**
+     * Command code for {@link MediaController2#setPlaylist(List, MediaMetadata2).
+     * <p>
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     */
+    public static final int COMMAND_CODE_PLAYLIST_SET_LIST = 19;
+
+    /**
+     * Command code for {@link MediaController2#getPlaylistMetadata()} ()}. This will expose
+     * metadata information to the controller.
+     * *
+     * Command code for {@link MediaController2#setPlaylist(List, MediaMetadata2)} and
+     * {@link MediaController2#updatePlaylistMetadata(MediaMetadata2)}.
+     * <p>
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
+     * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
+     */
+    public static final int COMMAND_CODE_PLAYLIST_GET_LIST_METADATA = 20;
+
+    /**
+     * Command code for {@link MediaController2#updatePlaylistMetadata(MediaMetadata2)}.
+     * <p>
+     * Command would be sent directly to the playlist controller if the session doesn't reject the
+     * request through the
      * {@link SessionCallback#onCommandRequest(MediaSession2, ControllerInfo, Command)}.
      */
-    public static final int COMMAND_CODE_SET_VOLUME = 15;
+    public static final int COMMAND_CODE_PLAYLIST_SET_LIST_METADATA = 21;
 
     /**
      * Command code for {@link MediaController2#playFromMediaId(String, Bundle)}.
      */
-    public static final int COMMAND_CODE_PLAY_FROM_MEDIA_ID = 16;
+    public static final int COMMAND_CODE_PLAY_FROM_MEDIA_ID = 22;
 
     /**
      * Command code for {@link MediaController2#playFromUri(Uri, Bundle)}.
      */
-    public static final int COMMAND_CODE_PLAY_FROM_URI = 17;
+    public static final int COMMAND_CODE_PLAY_FROM_URI = 23;
 
     /**
      * Command code for {@link MediaController2#playFromSearch(String, Bundle)}.
      */
-    public static final int COMMAND_CODE_PLAY_FROM_SEARCH = 18;
+    public static final int COMMAND_CODE_PLAY_FROM_SEARCH = 24;
 
     /**
      * Command code for {@link MediaController2#prepareFromMediaId(String, Bundle)}.
      */
-    public static final int COMMAND_CODE_PREPARE_FROM_MEDIA_ID = 19;
+    public static final int COMMAND_CODE_PREPARE_FROM_MEDIA_ID = 25;
 
     /**
      * Command code for {@link MediaController2#prepareFromUri(Uri, Bundle)}.
      */
-    public static final int COMMAND_CODE_PREPARE_FROM_URI = 20;
+    public static final int COMMAND_CODE_PREPARE_FROM_URI = 26;
 
     /**
      * Command code for {@link MediaController2#prepareFromSearch(String, Bundle)}.
      */
-    public static final int COMMAND_CODE_PREPARE_FROM_SEARCH = 21;
+    public static final int COMMAND_CODE_PREPARE_FROM_SEARCH = 27;
 
     /**
      * Command code for {@link MediaBrowser2} specific functions that allows navigation and search
-     * from the {@link MediaLibraryService2}. This would be ignored if a {@link MediaSession2},
-     * not {@link android.media.MediaLibraryService2.MediaLibrarySession}, specify this.
+     * from the {@link MediaLibraryService2}. This would be ignored for a {@link MediaSession2},
+     * not {@link android.media.MediaLibraryService2.MediaLibrarySession}.
      *
      * @see MediaBrowser2
      */
-    public static final int COMMAND_CODE_BROWSER = 22;
+    public static final int COMMAND_CODE_BROWSER = 28;
+
+    /**
+     * @hide
+     */
+    public static final int COMMAND_CODE_MAX = 28;
 
     /**
      * @hide
@@ -516,12 +596,12 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
          * @see #COMMAND_CODE_PLAYBACK_FAST_FORWARD
          * @see #COMMAND_CODE_PLAYBACK_REWIND
          * @see #COMMAND_CODE_PLAYBACK_SEEK_TO
-         * @see #COMMAND_CODE_PLAYBACK_SKIP_TO_PLAYLIST_ITEM
+         * @see #COMMAND_CODE_PLAYLIST_SKIP_TO_PLAYLIST_ITEM
          * @see #COMMAND_CODE_PLAYBACK_SET_PLAYLIST_PARAMS
-         * @see #COMMAND_CODE_PLAYLIST_ADD
-         * @see #COMMAND_CODE_PLAYLIST_REMOVE
-         * @see #COMMAND_CODE_PLAYLIST_GET
-         * @see #COMMAND_CODE_SET_VOLUME
+         * @see #COMMAND_CODE_PLAYLIST_ADD_ITEM
+         * @see #COMMAND_CODE_PLAYLIST_REMOVE_ITEM
+         * @see #COMMAND_CODE_PLAYLIST_GET_LIST
+         * @see #COMMAND_CODE_PLAYBACK_SET_VOLUME
          */
         public boolean onCommandRequest(@NonNull MediaSession2 session,
                 @NonNull ControllerInfo controller, @NonNull Command command) {
@@ -674,6 +754,36 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
          */
         public void onPrepareFromUri(@NonNull MediaSession2 session,
                 @NonNull ControllerInfo controller, @NonNull Uri uri, @Nullable Bundle extras) { }
+
+        /**
+         * Called when the player is <i>prepared</i>, i.e. it is ready to play the content
+         * referenced by the given data source.
+         * @param session the session for this event
+         * @param mpb the player for this event
+         * @param item the media item for which buffering is happening
+         */
+        public void onMediaPrepared(@NonNull MediaSession2 session, @NonNull MediaPlayerBase mpb,
+                @NonNull MediaItem2 item) { }
+
+        /**
+         * Called to indicate that the state of the player has changed.
+         * See {@link MediaPlayerBase#getPlayerState()} for polling the player state.
+         * @param session the session for this event
+         * @param mpb the player for this event
+         * @param state the new state of the player.
+         */
+        public void onPlayerStateChanged(@NonNull MediaSession2 session,
+                @NonNull MediaPlayerBase mpb, @PlayerState int state) { }
+
+        /**
+         * Called to report buffering events for a data source.
+         * @param session the session for this event
+         * @param mpb the player for this event
+         * @param item the media item for which buffering is happening.
+         * @param state the new buffering state.
+         */
+        public void onBufferingStateChanged(@NonNull MediaSession2 session,
+                @NonNull MediaPlayerBase mpb, @NonNull MediaItem2 item, @BuffState int state) { }
     };
 
     /**
@@ -1012,7 +1122,9 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
 
     /**
      * Parameter for the playlist.
+     * @hide
      */
+    // TODO(jaewan): Remove (b/74116823)
     public final static class PlaylistParams {
         /**
          * @hide
@@ -1307,16 +1419,10 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
         mProvider.stop_impl();
     }
 
-    /**
-     * Rewind playback
-     */
     public void skipToPrevious() {
         mProvider.skipToPrevious_impl();
     }
 
-    /**
-     * Rewind playback
-     */
     public void skipToNext() {
         mProvider.skipToNext_impl();
     }
@@ -1356,17 +1462,6 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
     }
 
     /**
-     * Skip to the item in the play list.
-     *
-     * @param item item in the play list you want to play
-     * @throws IllegalArgumentException if the play list is null
-     * @throws NullPointerException if index is outside play list range
-     */
-    public void skipToPlaylistItem(MediaItem2 item) {
-        mProvider.skipToPlaylistItem_impl(item);
-    }
-
-    /**
      * @hide
      */
     public void skipForward() {
@@ -1381,80 +1476,14 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
     }
 
     /**
-     * Set a list of {@link MediaItem2} as the current play list.
-     *
-     * @param playlist A list of {@link MediaItem2} objects to set as a play list.
-     * @throws IllegalArgumentException if given {@param playlist} is null.
-     */
-    public void setPlaylist(@NonNull List<MediaItem2> playlist) {
-        mProvider.setPlaylist_impl(playlist);
-    }
-
-    /**
-     * Remove the media item in the play list.
-     * <p>
-     * If the item is the currently playing item of the playlist, current playback
-     * will be stopped and playback moves to next source in the list.
-     *
-     * @throws IllegalArgumentException if the play list is null
-     */
-    public void removePlaylistItem(MediaItem2 item) {
-        mProvider.removePlaylistItem_impl(item);
-    }
-
-    /**
-     * Add the media item to the play list at position index.
-     * <p>
-     * This will not change the currently playing media item.
-     * If index is less than or equal to the current index of the play list,
-     * the current index of the play list will be incremented correspondingly.
-     *
-     * @param index the index you want to add
-     * @param item the media item you want to add
-     * @throws IndexOutOfBoundsException if index is outside play list range
-     */
-    @Override
-    public void addPlaylistItem(int index, @NonNull MediaItem2 item) {
-        mProvider.addPlaylistItem_impl(index, item);
-    }
-
-    /**
-     * Replace the media item at index in the playlist.
-     * @param index the index of the item to replace
-     * @param item the new item
-     */
-    @Override
-    public void replacePlaylistItem(int index, @NonNull MediaItem2 item) {
-        mProvider.replacePlaylistItem_impl(index, item);
-    }
-
-    /**
-     * Return the playlist which is lastly set.
-     *
-     * @return playlist
-     */
-    @Override
-    public List<MediaItem2> getPlaylist() {
-        return mProvider.getPlaylist_impl();
-    }
-
-    /**
-     * Return currently playing media item.
-     *
-     * @return currently playing media item
-     */
-    @Override
-    public MediaItem2 getCurrentPlaylistItem() {
-        return mProvider.getCurrentPlaylistItem_impl();
-    }
-
-    /**
      * Sets the {@link PlaylistParams} for the current play list. Repeat/shuffle mode and metadata
      * for the list can be set by calling this method.
      *
      * @param params A {@link PlaylistParams} object to set.
      * @throws IllegalArgumentException if given {@param param} is null.
+     * @hide
      */
+    // TODO(jaewan): Remove (b/74116823)
     public void setPlaylistParams(PlaylistParams params) {
         mProvider.setPlaylistParams_impl(params);
     }
@@ -1462,7 +1491,9 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
     /**
      * Returns the {@link PlaylistParams} for the current play list.
      * Returns {@code null} if not set.
+     * @hide
      */
+    // TODO(jaewan): Remove (b/74116823)
     public PlaylistParams getPlaylistParams() {
         return mProvider.getPlaylistParams_impl();
     }
@@ -1532,4 +1563,152 @@ public class MediaSession2 implements AutoCloseable, MediaPlaylistController {
     public void setPlaybackSpeed(float speed) {
         // TODO(jaewan): implement this (b/74093080)
     }
+
+    /**
+     * Register {@link MediaPlaylistController.PlaylistEventCallback} to listen changes in the
+     * underlying {@link MediaPlaylistController}, regardless of the change in the controller.
+     * <p>
+     * Registered callbacks will be also called when the controller is changed.
+     *
+     * @param executor a callback Executor
+     * @param callback a PlaylistEventCallback
+     * @throws IllegalArgumentException if executor or callback is {@code null}.
+     */
+    @Override
+    public void registerPlaylistControllerCallback(@NonNull @CallbackExecutor Executor executor,
+            @NonNull PlaylistEventCallback callback) {
+        // TODO(jaewan): Implement (b/74169681)
+        //mProvider.registerPlaylistControllerCallback_impl(executor, callback);
+    }
+
+    /**
+     * Unregister the previously registered {@link MediaPlaylistController.PlaylistEventCallback}.
+     *
+     * @param callback the callback to be removed
+     * @throws IllegalArgumentException if the callback is {@code null}.
+     */
+    @Override
+    public void unregisterPlaylistControllerCallback(@NonNull PlaylistEventCallback callback) {
+        // TODO(jaewan): Implement (b/74169681)
+        //mProvider.unregisterPlaylistControllerCallback_impl(callback);
+    }
+
+    /**
+     * Return the playlist which is lastly set.
+     *
+     * @return playlist
+     */
+    @Override
+    public List<MediaItem2> getPlaylist() {
+        return mProvider.getPlaylist_impl();
+    }
+
+    /**
+     * Set a list of {@link MediaItem2} as the current play list.
+     *
+     * @param playlist A list of {@link MediaItem2} objects to set as a play list.
+     * @throws IllegalArgumentException if given {@param playlist} is null.
+     * @hide
+     */
+    // TODO(jaewan): Remove
+    public void setPlaylist(@NonNull List<MediaItem2> playlist) {
+        mProvider.setPlaylist_impl(playlist);
+    }
+
+    @Override
+    public void setPlaylist(@NonNull List<MediaItem2> list, @Nullable MediaMetadata2 metadata) {
+        // TODO(jaewan): Implement (b/74174649)
+    }
+
+    /**
+     * Skip to the item in the play list.
+     *
+     * @param item item in the play list you want to play
+     * @throws IllegalArgumentException if the play list is null
+     * @throws NullPointerException if index is outside play list range
+     */
+    public void skipToPlaylistItem(MediaItem2 item) {
+        mProvider.skipToPlaylistItem_impl(item);
+    }
+
+    @Override
+    public MediaMetadata2 getPlaylistMetadata() {
+        // TODO(jaewan): Implement (b/74174649)
+        return null;
+    }
+
+    /**
+     * Add the media item to the play list at position index.
+     * <p>
+     * This will not change the currently playing media item.
+     * If index is less than or equal to the current index of the play list,
+     * the current index of the play list will be incremented correspondingly.
+     *
+     * @param index the index you want to add
+     * @param item the media item you want to add
+     * @throws IndexOutOfBoundsException if index is outside play list range
+     */
+    @Override
+    public void addPlaylistItem(int index, @NonNull MediaItem2 item) {
+        mProvider.addPlaylistItem_impl(index, item);
+    }
+
+    /**
+     * Remove the media item in the play list.
+     * <p>
+     * If the item is the currently playing item of the playlist, current playback
+     * will be stopped and playback moves to next source in the list.
+     *
+     * @throws IllegalArgumentException if the play list is null
+     */
+    public void removePlaylistItem(MediaItem2 item) {
+        mProvider.removePlaylistItem_impl(item);
+    }
+
+    /**
+     * Replace the media item at index in the playlist.
+     * @param index the index of the item to replace
+     * @param item the new item
+     */
+    @Override
+    public void replacePlaylistItem(int index, @NonNull MediaItem2 item) {
+        mProvider.replacePlaylistItem_impl(index, item);
+    }
+
+    /**
+     * Return currently playing media item.
+     *
+     * @return currently playing media item
+     */
+    @Override
+    public MediaItem2 getCurrentPlaylistItem() {
+        return mProvider.getCurrentPlaylistItem_impl();
+    }
+
+    @Override
+    public void updatePlaylistMetadata(@Nullable MediaMetadata2 metadata) {
+        // TODO(jaewan): Implement (b/74174649)
+    }
+
+    @Override
+    public int getRepeatMode() {
+        // TODO(jaewan): Implement (b/74118768)
+        return 0;
+    }
+
+    @Override
+    public void setRepeatMode(int repeatMode) {
+        // TODO(jaewan): Implement (b/74118768)
+    }
+
+    @Override
+    public int getShuffleMode() {
+        // TODO(jaewan): Implement (b/74118768)
+        return 0;
+    }
+
+    @Override
+    public void setShuffleMode(int shuffleMode) {
+        // TODO(jaewan): Implement (b/74118768)
+    }
 }