Remove unnecessary SDK_INT checks

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/mediacodec/MediaCodecRenderer.java

@@ -2613,11 +2613,7 @@ public abstract class MediaCodecRenderer extends BaseRenderer {
    *     buffer with {@link MediaCodec#BUFFER_FLAG_END_OF_STREAM} set. False otherwise.
    */
   private static boolean codecNeedsEosFlushWorkaround(String name) {
-    return (Util.SDK_INT <= 23 && "OMX.google.vorbis.decoder".equals(name))
+    return Util.SDK_INT <= 23 && "OMX.google.vorbis.decoder".equals(name);
-        || (Util.SDK_INT == 19
-            && ("hb2000".equals(Util.DEVICE) || "stvm8".equals(Util.DEVICE))
-            && ("OMX.amlogic.avc.decoder.awesome".equals(name)
-                || "OMX.amlogic.avc.decoder.awesome.secure".equals(name)));
   }
 
   /**

libraries/session/src/main/java/androidx/media3/session/DefaultMediaNotificationProvider.java

@@ -366,12 +366,6 @@ public class DefaultMediaNotificationProvider implements MediaNotification.Provi
       }
     }
 
-    if (player.isCommandAvailable(COMMAND_STOP)) {
-      // We must include a cancel intent for pre-L devices.
-      mediaStyle.setCancelButtonIntent(
-          actionFactory.createMediaActionPendingIntent(mediaSession, COMMAND_STOP));
-    }
-
     long playbackStartTimeMs = getPlaybackStartTimeEpochMs(player);
     boolean displayElapsedTimeWithChronometer = playbackStartTimeMs != C.TIME_UNSET;
     builder

libraries/session/src/main/java/androidx/media3/session/legacy/AudioAttributesCompat.java

@@ -308,10 +308,9 @@ public class AudioAttributesCompat {
     }
     if (Build.VERSION.SDK_INT >= 26) {
       return new AudioAttributesCompat(new AudioAttributesImplApi26((AudioAttributes) aa));
-    } else if (Build.VERSION.SDK_INT >= 21) {
+    } else {
       return new AudioAttributesCompat(new AudioAttributesImplApi21((AudioAttributes) aa));
     }
-    return null;
   }
 
   // The rest of this file implements an approximation to AudioAttributes using old stream types
@@ -377,10 +376,8 @@ public class AudioAttributesCompat {
         mBuilderImpl = new AudioAttributesImplBase.Builder();
       } else if (Build.VERSION.SDK_INT >= 26) {
         mBuilderImpl = new AudioAttributesImplApi26.Builder();
-      } else if (Build.VERSION.SDK_INT >= 21) {
-        mBuilderImpl = new AudioAttributesImplApi21.Builder();
       } else {
-        mBuilderImpl = new AudioAttributesImplBase.Builder();
+        mBuilderImpl = new AudioAttributesImplApi21.Builder();
       }
     }
 
@@ -394,10 +391,8 @@ public class AudioAttributesCompat {
         mBuilderImpl = new AudioAttributesImplBase.Builder(aa);
       } else if (Build.VERSION.SDK_INT >= 26) {
         mBuilderImpl = new AudioAttributesImplApi26.Builder(checkNotNull(aa.unwrap()));
-      } else if (Build.VERSION.SDK_INT >= 21) {
-        mBuilderImpl = new AudioAttributesImplApi21.Builder(checkNotNull(aa.unwrap()));
       } else {
-        mBuilderImpl = new AudioAttributesImplBase.Builder(aa);
+        mBuilderImpl = new AudioAttributesImplApi21.Builder(checkNotNull(aa.unwrap()));
       }
     }
 

libraries/session/src/main/java/androidx/media3/session/legacy/LegacyParcelableUtil.java

@@ -88,7 +88,7 @@ public final class LegacyParcelableUtil {
   // TODO: b/335804969 - Remove this workaround once the bug fix is in the androidx.media dependency
   @SuppressWarnings("unchecked")
   private static <T> T maybeApplyMediaDescriptionParcelableBugWorkaround(T value) {
-    if (Util.SDK_INT < 21 || Util.SDK_INT >= 23) {
+    if (Util.SDK_INT >= 23) {
       return value;
     }
     if (value instanceof android.support.v4.media.MediaBrowserCompat.MediaItem) {

libraries/session/src/main/java/androidx/media3/session/legacy/MediaBrowserCompat.java

@@ -73,6 +73,7 @@ import android.support.v4.os.ResultReceiver;
 import android.text.TextUtils;
 import android.util.Log;
 import androidx.annotation.IntDef;
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
 import androidx.annotation.RestrictTo;
@@ -203,10 +204,8 @@ public final class MediaBrowserCompat {
       mImpl = new MediaBrowserImplApi26(context, serviceComponent, callback, rootHints);
     } else if (Build.VERSION.SDK_INT >= 23) {
       mImpl = new MediaBrowserImplApi23(context, serviceComponent, callback, rootHints);
-    } else if (Build.VERSION.SDK_INT >= 21) {
-      mImpl = new MediaBrowserImplApi21(context, serviceComponent, callback, rootHints);
     } else {
-      mImpl = new MediaBrowserImplBase(context, serviceComponent, callback, rootHints);
+      mImpl = new MediaBrowserImplApi21(context, serviceComponent, callback, rootHints);
     }
   }
 
@@ -463,7 +462,7 @@ public final class MediaBrowserCompat {
      */
     @Nullable
     public static MediaItem fromMediaItem(@Nullable Object itemObj) {
-      if (itemObj == null || Build.VERSION.SDK_INT < 21) {
+      if (itemObj == null) {
         return null;
       }
       MediaBrowser.MediaItem itemFwk = (MediaBrowser.MediaItem) itemObj;
@@ -484,7 +483,7 @@ public final class MediaBrowserCompat {
      */
     @Nullable
     public static List<MediaItem> fromMediaItemList(@Nullable List<?> itemList) {
-      if (itemList == null || Build.VERSION.SDK_INT < 21) {
+      if (itemList == null) {
         return null;
       }
       List<MediaItem> items = new ArrayList<>(itemList.size());
@@ -599,11 +598,7 @@ public final class MediaBrowserCompat {
     @Nullable ConnectionCallbackInternal mConnectionCallbackInternal;
 
     public ConnectionCallback() {
-      if (Build.VERSION.SDK_INT >= 21) {
       mConnectionCallbackFwk = new ConnectionCallbackApi21();
-      } else {
-        mConnectionCallbackFwk = null;
-      }
     }
 
     /**
@@ -676,7 +671,7 @@ public final class MediaBrowserCompat {
 
   /** Callbacks for subscription related events. */
   public abstract static class SubscriptionCallback {
-    @Nullable final MediaBrowser.SubscriptionCallback mSubscriptionCallbackFwk;
+    @NonNull final MediaBrowser.SubscriptionCallback mSubscriptionCallbackFwk;
     final IBinder mToken;
     @Nullable WeakReference<Subscription> mSubscriptionRef;
 
@@ -684,10 +679,8 @@ public final class MediaBrowserCompat {
       mToken = new Binder();
       if (Build.VERSION.SDK_INT >= 26) {
         mSubscriptionCallbackFwk = new SubscriptionCallbackApi26();
-      } else if (Build.VERSION.SDK_INT >= 21) {
-        mSubscriptionCallbackFwk = new SubscriptionCallbackApi21();
       } else {
-        mSubscriptionCallbackFwk = null;
+        mSubscriptionCallbackFwk = new SubscriptionCallbackApi21();
       }
     }
 
@@ -1739,7 +1732,7 @@ public final class MediaBrowserCompat {
       if (mServiceBinderWrapper == null) {
         // TODO: When MediaBrowser is connected to framework's MediaBrowserService,
         // subscribe with options won't work properly.
-        mBrowserFwk.subscribe(parentId, checkNotNull(callback.mSubscriptionCallbackFwk));
+        mBrowserFwk.subscribe(parentId, callback.mSubscriptionCallbackFwk);
       } else {
         try {
           mServiceBinderWrapper.addSubscription(
@@ -2087,9 +2080,9 @@ public final class MediaBrowserCompat {
       // This is to prevent ClassNotFoundException when options has Parcelable in it.
       if (mServiceBinderWrapper == null || mServiceVersion < SERVICE_VERSION_2) {
         if (options == null) {
-          mBrowserFwk.subscribe(parentId, checkNotNull(callback.mSubscriptionCallbackFwk));
+          mBrowserFwk.subscribe(parentId, callback.mSubscriptionCallbackFwk);
         } else {
-          mBrowserFwk.subscribe(parentId, options, checkNotNull(callback.mSubscriptionCallbackFwk));
+          mBrowserFwk.subscribe(parentId, options, callback.mSubscriptionCallbackFwk);
         }
       } else {
         super.subscribe(parentId, options, callback);
@@ -2104,7 +2097,7 @@ public final class MediaBrowserCompat {
         if (callback == null) {
           mBrowserFwk.unsubscribe(parentId);
         } else {
-          mBrowserFwk.unsubscribe(parentId, checkNotNull(callback.mSubscriptionCallbackFwk));
+          mBrowserFwk.unsubscribe(parentId, callback.mSubscriptionCallbackFwk);
         }
       } else {
         super.unsubscribe(parentId, callback);

libraries/session/src/main/java/androidx/media3/session/legacy/MediaBrowserServiceCompat.java

@@ -1328,10 +1328,8 @@ public abstract class MediaBrowserServiceCompat extends Service {
       mImpl = new MediaBrowserServiceImplApi26();
     } else if (Build.VERSION.SDK_INT >= 23) {
       mImpl = new MediaBrowserServiceImplApi23();
-    } else if (Build.VERSION.SDK_INT >= 21) {
-      mImpl = new MediaBrowserServiceImplApi21();
     } else {
-      mImpl = new MediaBrowserServiceImplBase();
+      mImpl = new MediaBrowserServiceImplApi21();
     }
     mImpl.onCreate();
   }

libraries/session/src/main/java/androidx/media3/session/legacy/MediaControllerCompat.java

@@ -40,6 +40,7 @@ import android.text.TextUtils;
 import android.util.Log;
 import android.view.KeyEvent;
 import androidx.annotation.GuardedBy;
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
 import androidx.annotation.RestrictTo;
@@ -142,9 +143,12 @@ public final class MediaControllerCompat {
         .getWindow()
         .getDecorView()
         .setTag(R.id.media_controller_compat_view_tag, mediaController);
-    if (android.os.Build.VERSION.SDK_INT >= 21) {
+    MediaController controllerFwk = null;
-      MediaControllerImplApi21.setMediaController(activity, mediaController);
+    if (mediaController != null) {
+      Object sessionTokenObj = mediaController.getSessionToken().getToken();
+      controllerFwk = new MediaController(activity, (MediaSession.Token) sessionTokenObj);
     }
+    activity.setMediaController(controllerFwk);
   }
 
   /**
@@ -162,11 +166,16 @@ public final class MediaControllerCompat {
     Object tag = activity.getWindow().getDecorView().getTag(R.id.media_controller_compat_view_tag);
     if (tag instanceof MediaControllerCompat) {
       return (MediaControllerCompat) tag;
-    } else if (android.os.Build.VERSION.SDK_INT >= 21) {
+    } else {
-      return MediaControllerImplApi21.getMediaController(activity);
+      MediaController controllerFwk = activity.getMediaController();
-    }
+      if (controllerFwk == null) {
         return null;
       }
+      MediaSession.Token sessionTokenFwk = controllerFwk.getSessionToken();
+      return new MediaControllerCompat(
+          activity, MediaSessionCompat.Token.fromToken(sessionTokenFwk));
+    }
+  }
 
   @SuppressWarnings("WeakerAccess") /* synthetic access */
   static void validateCustomAction(@Nullable String action, @Nullable Bundle args) {
@@ -221,10 +230,8 @@ public final class MediaControllerCompat {
 
     if (Build.VERSION.SDK_INT >= 29) {
       mImpl = new MediaControllerImplApi29(context, sessionToken);
-    } else if (Build.VERSION.SDK_INT >= 21) {
-      mImpl = new MediaControllerImplApi21(context, sessionToken);
     } else {
-      mImpl = new MediaControllerImplBase(sessionToken);
+      mImpl = new MediaControllerImplApi21(context, sessionToken);
     }
   }
 
@@ -649,19 +656,14 @@ public final class MediaControllerCompat {
    * #registerCallback}
    */
   public abstract static class Callback implements IBinder.DeathRecipient {
-    @Nullable final MediaController.Callback mCallbackFwk;
+    @NonNull final MediaController.Callback mCallbackFwk;
     @Nullable MessageHandler mHandler;
     @Nullable IMediaControllerCallback mIControllerCallback;
 
     // Sharing this in constructor
     @SuppressWarnings({"assignment.type.incompatible", "argument.type.incompatible"})
     public Callback() {
-      if (android.os.Build.VERSION.SDK_INT >= 21) {
       mCallbackFwk = new MediaControllerCallbackApi21(this);
-      } else {
-        mCallbackFwk = null;
-        mIControllerCallback = new StubCompat(this);
-      }
     }
 
     /**
@@ -2000,7 +2002,7 @@ public final class MediaControllerCompat {
 
     @Override
     public final void registerCallback(Callback callback, Handler handler) {
-      mControllerFwk.registerCallback(checkNotNull(callback.mCallbackFwk), handler);
+      mControllerFwk.registerCallback(callback.mCallbackFwk, handler);
       synchronized (mLock) {
         IMediaSession extraBinder = mSessionToken.getExtraBinder();
         if (extraBinder != null) {
@@ -2022,7 +2024,7 @@ public final class MediaControllerCompat {
 
     @Override
     public final void unregisterCallback(Callback callback) {
-      mControllerFwk.unregisterCallback(checkNotNull(callback.mCallbackFwk));
+      mControllerFwk.unregisterCallback(callback.mCallbackFwk);
       synchronized (mLock) {
         IMediaSession extraBinder = mSessionToken.getExtraBinder();
         if (extraBinder != null) {
@@ -2149,7 +2151,7 @@ public final class MediaControllerCompat {
 
     @Override
     public int getRatingType() {
-      if (android.os.Build.VERSION.SDK_INT < 22) {
+      if (android.os.Build.VERSION.SDK_INT == 21) {
         try {
           IMediaSession extraBinder = mSessionToken.getExtraBinder();
           if (extraBinder != null) {
@@ -2302,27 +2304,6 @@ public final class MediaControllerCompat {
       mPendingCallbacks.clear();
     }
 
-    @SuppressWarnings("argument.type.incompatible") // Activity.setMediaController is not annotated
-    static void setMediaController(Activity activity, MediaControllerCompat mediaControllerCompat) {
-      MediaController controllerFwk = null;
-      if (mediaControllerCompat != null) {
-        Object sessionTokenObj = mediaControllerCompat.getSessionToken().getToken();
-        controllerFwk = new MediaController(activity, (MediaSession.Token) sessionTokenObj);
-      }
-      activity.setMediaController(controllerFwk);
-    }
-
-    @Nullable
-    static MediaControllerCompat getMediaController(Activity activity) {
-      MediaController controllerFwk = activity.getMediaController();
-      if (controllerFwk == null) {
-        return null;
-      }
-      MediaSession.Token sessionTokenFwk = controllerFwk.getSessionToken();
-      return new MediaControllerCompat(
-          activity, MediaSessionCompat.Token.fromToken(sessionTokenFwk));
-    }
-
     private static class ExtraBinderRequestResultReceiver extends ResultReceiver {
       private WeakReference<MediaControllerImplApi21> mMediaControllerImpl;
 

libraries/session/src/main/java/androidx/media3/session/legacy/MediaDescriptionCompat.java

@@ -294,19 +294,8 @@ public final class MediaDescriptionCompat implements Parcelable {
 
   @Override
   public void writeToParcel(Parcel dest, int flags) {
-    if (Build.VERSION.SDK_INT < 21) {
-      dest.writeString(mMediaId);
-      TextUtils.writeToParcel(mTitle, dest, flags);
-      TextUtils.writeToParcel(mSubtitle, dest, flags);
-      TextUtils.writeToParcel(mDescription, dest, flags);
-      dest.writeParcelable(mIcon, flags);
-      dest.writeParcelable(mIconUri, flags);
-      dest.writeBundle(mExtras);
-      dest.writeParcelable(mMediaUri, flags);
-    } else {
     ((MediaDescription) getMediaDescription()).writeToParcel(dest, flags);
   }
-  }
 
   @Override
   public String toString() {
@@ -365,7 +354,7 @@ public final class MediaDescriptionCompat implements Parcelable {
   @Nullable
   @SuppressWarnings("deprecation")
   public static MediaDescriptionCompat fromMediaDescription(Object descriptionObj) {
-    if (descriptionObj != null && Build.VERSION.SDK_INT >= 21) {
+    if (descriptionObj != null) {
       Builder bob = new Builder();
       MediaDescription description = (MediaDescription) descriptionObj;
       bob.setMediaId(description.getMediaId());
@@ -416,13 +405,9 @@ public final class MediaDescriptionCompat implements Parcelable {
       new Parcelable.Creator<MediaDescriptionCompat>() {
         @Override
         public MediaDescriptionCompat createFromParcel(Parcel in) {
-          if (Build.VERSION.SDK_INT < 21) {
-            return new MediaDescriptionCompat(in);
-          } else {
           return checkNotNull(
               fromMediaDescription(MediaDescription.CREATOR.createFromParcel(in)));
         }
-        }
 
         @Override
         public MediaDescriptionCompat[] newArray(int size) {

libraries/session/src/main/java/androidx/media3/session/legacy/MediaMetadataCompat.java

@@ -22,7 +22,6 @@ import android.annotation.SuppressLint;
 import android.graphics.Bitmap;
 import android.media.MediaMetadata;
 import android.net.Uri;
-import android.os.Build;
 import android.os.Bundle;
 import android.os.Parcel;
 import android.os.Parcelable;
@@ -563,7 +562,7 @@ public final class MediaMetadataCompat implements Parcelable {
    */
   @Nullable
   public static MediaMetadataCompat fromMediaMetadata(@Nullable Object metadataObj) {
-    if (metadataObj != null && Build.VERSION.SDK_INT >= 21) {
+    if (metadataObj != null) {
       Parcel p = Parcel.obtain();
       ((MediaMetadata) metadataObj).writeToParcel(p, 0);
       p.setDataPosition(0);

libraries/session/src/main/java/androidx/media3/session/legacy/MediaSessionCompat.java

@@ -47,7 +47,6 @@ import android.os.Binder;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.Handler;
-import android.os.IBinder;
 import android.os.Looper;
 import android.os.Message;
 import android.os.Parcel;
@@ -459,7 +458,6 @@ public class MediaSessionCompat {
               Build.VERSION.SDK_INT >= 31 ? PendingIntent.FLAG_MUTABLE : 0);
     }
 
-    if (android.os.Build.VERSION.SDK_INT >= 21) {
     if (android.os.Build.VERSION.SDK_INT >= 29) {
       mImpl = new MediaSessionImplApi29(context, tag, session2Token, sessionInfo);
     } else if (android.os.Build.VERSION.SDK_INT >= 28) {
@@ -474,11 +472,6 @@ public class MediaSessionCompat {
     Handler handler = new Handler(myLooper != null ? myLooper : Looper.getMainLooper());
     setCallback(new Callback() {}, handler);
     mImpl.setMediaButtonReceiver(mbrIntent);
-    } else {
-      mImpl =
-          new MediaSessionImplApi19(
-              context, tag, mbrComponent, mbrIntent, session2Token, sessionInfo);
-    }
     mController = new MediaControllerCompat(context, this);
 
     if (sMaxBitmapSize == 0) {
@@ -915,7 +908,7 @@ public class MediaSessionCompat {
   @Nullable
   public static MediaSessionCompat fromMediaSession(
       @Nullable Context context, @Nullable Object mediaSession) {
-    if (Build.VERSION.SDK_INT < 21 || context == null || mediaSession == null) {
+    if (context == null || mediaSession == null) {
       return null;
     }
     MediaSessionImpl impl;
@@ -1001,7 +994,8 @@ public class MediaSessionCompat {
    */
   public abstract static class Callback {
     final Object mLock = new Object();
-    @Nullable final MediaSession.Callback mCallbackFwk;
+    @androidx.annotation.NonNull
+    final MediaSession.Callback mCallbackFwk;
     private boolean mMediaPlayPausePendingOnHandler;
 
     @GuardedBy("mLock")
@@ -1013,11 +1007,7 @@ public class MediaSessionCompat {
     CallbackHandler mCallbackHandler;
 
     public Callback() {
-      if (android.os.Build.VERSION.SDK_INT >= 21) {
       mCallbackFwk = new MediaSessionCallbackApi21();
-      } else {
-        mCallbackFwk = null;
-      }
       mSessionImpl = new WeakReference<>(null);
     }
 
@@ -1845,11 +1835,7 @@ public class MediaSessionCompat {
 
     @Override
     public void writeToParcel(Parcel dest, int flags) {
-      if (android.os.Build.VERSION.SDK_INT >= 21) {
       dest.writeParcelable((Parcelable) mInner, flags);
-      } else {
-        dest.writeStrongBinder((IBinder) mInner);
-      }
     }
 
     @Override
@@ -1963,12 +1949,7 @@ public class MediaSessionCompat {
           @SuppressWarnings("deprecation")
           @Override
           public Token createFromParcel(Parcel in) {
-            Object inner;
+            Object inner = in.readParcelable(null);
-            if (android.os.Build.VERSION.SDK_INT >= 21) {
-              inner = in.readParcelable(null);
-            } else {
-              inner = in.readStrongBinder();
-            }
             return new Token(checkNotNull(inner));
           }
 
@@ -2048,13 +2029,11 @@ public class MediaSessionCompat {
     /**
      * Gets the underlying {@link android.media.session.MediaSession.QueueItem}.
      *
-     * <p>On builds before {@link android.os.Build.VERSION_CODES#LOLLIPOP} null is returned.
+     * @return The underlying {@link android.media.session.MediaSession.QueueItem}.
-     *
-     * @return The underlying {@link android.media.session.MediaSession.QueueItem} or null.
      */
-    @Nullable
+    @androidx.annotation.NonNull
     public Object getQueueItem() {
-      if (mItemFwk != null || android.os.Build.VERSION.SDK_INT < 21) {
+      if (mItemFwk != null) {
         return mItemFwk;
       }
       mItemFwk =
@@ -2082,15 +2061,13 @@ public class MediaSessionCompat {
      * Creates a list of {@link QueueItem} objects from a framework {@link
      * android.media.session.MediaSession.QueueItem} object list.
      *
-     * <p>This method is only supported on API 21+. On API 20 and below, it returns null.
-     *
      * @param itemList A list of {@link android.media.session.MediaSession.QueueItem} objects.
      * @return An equivalent list of {@link QueueItem} objects, or null if none.
      */
     @Nullable
     public static List<QueueItem> fromQueueItemList(
         @Nullable List<? extends @NonNull Object> itemList) {
-      if (itemList == null || Build.VERSION.SDK_INT < 21) {
+      if (itemList == null) {
         return null;
       }
       List<QueueItem> items = new ArrayList<>(itemList.size());

libraries/session/src/main/java/androidx/media3/session/legacy/MediaSessionManager.java

@@ -71,10 +71,8 @@ public final class MediaSessionManager {
   private MediaSessionManager(Context context) {
     if (Build.VERSION.SDK_INT >= 28) {
       mImpl = new MediaSessionManagerImplApi28(context);
-    } else if (Build.VERSION.SDK_INT >= 21) {
-      mImpl = new MediaSessionManagerImplApi21(context);
     } else {
-      mImpl = new MediaSessionManagerImplBase(context);
+      mImpl = new MediaSessionManagerImplApi21(context);
     }
   }
 

libraries/session/src/main/java/androidx/media3/session/legacy/PlaybackStateCompat.java

@@ -847,7 +847,7 @@ public final class PlaybackStateCompat implements Parcelable {
    */
   @Nullable
   public static PlaybackStateCompat fromPlaybackState(@Nullable Object stateObj) {
-    if (stateObj != null && Build.VERSION.SDK_INT >= 21) {
+    if (stateObj != null) {
       PlaybackState stateFwk = (PlaybackState) stateObj;
       List<PlaybackState.CustomAction> customActionFwks = stateFwk.getCustomActions();
       List<PlaybackStateCompat.CustomAction> customActions = null;
@@ -896,7 +896,7 @@ public final class PlaybackStateCompat implements Parcelable {
    */
   @Nullable
   public Object getPlaybackState() {
-    if (mStateFwk == null && Build.VERSION.SDK_INT >= 21) {
+    if (mStateFwk == null) {
       PlaybackState.Builder builder = new PlaybackState.Builder()
           .setState(mState, mPosition, mSpeed, mUpdateTime)
           .setBufferedPosition(mBufferedPosition)
@@ -998,14 +998,12 @@ public final class PlaybackStateCompat implements Parcelable {
      * Gets the underlying framework {@link android.media.session.PlaybackState.CustomAction}
      * object.
      *
-     * <p>This method is only supported on API 21+.
-     *
      * @return An equivalent {@link android.media.session.PlaybackState.CustomAction} object, or
      *     null if none.
      */
     @Nullable
     public Object getCustomAction() {
-      if (mCustomActionFwk != null || Build.VERSION.SDK_INT < 21) {
+      if (mCustomActionFwk != null) {
         return mCustomActionFwk;
       }
 

libraries/session/src/main/java/androidx/media3/session/legacy/VolumeProviderCompat.java

@@ -130,10 +130,8 @@ public abstract class VolumeProviderCompat {
    */
   public final void setCurrentVolume(int currentVolume) {
     mCurrentVolume = currentVolume;
-    if (Build.VERSION.SDK_INT >= 21) {
     VolumeProvider volumeProviderFwk = (VolumeProvider) getVolumeProvider();
     volumeProviderFwk.setCurrentVolume(currentVolume);
-    }
     if (mCallback != null) {
       mCallback.onVolumeChanged(this);
     }

libraries/test_exoplayer_playback/src/androidTest/java/androidx/media3/test/exoplayer/playback/gts/DebugRenderersFactory.java

@@ -237,16 +237,10 @@ import java.util.ArrayList;
     }
 
     @Override
-    protected void renderOutputBuffer(MediaCodecAdapter codec, int index, long presentationTimeUs) {
+    protected void renderOutputBuffer(
-      skipToPositionBeforeRenderingFirstFrame = false;
-      super.renderOutputBuffer(codec, index, presentationTimeUs);
-    }
-
-    @Override
-    protected void renderOutputBufferV21(
         MediaCodecAdapter codec, int index, long presentationTimeUs, long releaseTimeNs) {
       skipToPositionBeforeRenderingFirstFrame = false;
-      super.renderOutputBufferV21(codec, index, presentationTimeUs, releaseTimeNs);
+      super.renderOutputBuffer(codec, index, presentationTimeUs, releaseTimeNs);
     }
 
     @Override

libraries/test_session_current/src/androidTest/java/androidx/media3/session/legacy/AudioAttributesCompatTest.java

@@ -21,7 +21,6 @@ import static org.hamcrest.core.IsNot.not;
 
 import android.media.AudioAttributes;
 import android.media.AudioManager;
-import android.os.Build;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 import androidx.test.filters.SdkSuppress;
 import org.junit.After;
@@ -54,9 +53,6 @@ public class AudioAttributesCompatTest {
   @Before
   @SdkSuppress(minSdkVersion = 21)
   public void setUpApi21() {
-    if (Build.VERSION.SDK_INT < 21) {
-      return;
-    }
     mMediaAA =
         new AudioAttributes.Builder()
             .setContentType(AudioAttributes.CONTENT_TYPE_MUSIC)

libraries/test_utils/src/main/java/androidx/media3/test/utils/DecodeOneFrameUtil.java

@@ -35,7 +35,6 @@ import androidx.media3.common.Format;
 import androidx.media3.common.MimeTypes;
 import androidx.media3.common.util.MediaFormatUtil;
 import androidx.media3.common.util.UnstableApi;
-import androidx.media3.common.util.Util;
 import java.io.IOException;
 import java.nio.ByteBuffer;
 
@@ -209,7 +208,7 @@ public final class DecodeOneFrameUtil {
     // Format must not include KEY_FRAME_RATE on API21.
     // https://developer.android.com/reference/android/media/MediaCodecList#findDecoderForFormat(android.media.MediaFormat)
     float frameRate = Format.NO_VALUE;
-    if (Util.SDK_INT == 21 && format.containsKey(MediaFormat.KEY_FRAME_RATE)) {
+    if (format.containsKey(MediaFormat.KEY_FRAME_RATE)) {
       try {
         frameRate = format.getFloat(MediaFormat.KEY_FRAME_RATE);
       } catch (ClassCastException e) {
@@ -221,9 +220,7 @@ public final class DecodeOneFrameUtil {
 
     @Nullable String mediaCodecName = mediaCodecList.findDecoderForFormat(format);
 
-    if (Util.SDK_INT == 21) {
     MediaFormatUtil.maybeSetInteger(format, MediaFormat.KEY_FRAME_RATE, round(frameRate));
-    }
     return mediaCodecName;
   }
 

libraries/transformer/src/androidTest/java/androidx/media3/transformer/mh/performance/ExoplayerEffectPlaybackSeekTest.java

@@ -102,16 +102,15 @@ public final class ExoplayerEffectPlaybackSeekTest {
         new MediaCodecVideoRenderer(context, MediaCodecSelector.DEFAULT) {
           private int numberOfFramesRendered;
 
-          // Overriding V21 is sufficient as we don't have test running below API26.
           @Override
-          protected void renderOutputBufferV21(
+          protected void renderOutputBuffer(
               MediaCodecAdapter codec, int index, long presentationTimeUs, long releaseTimeNs) {
             numberOfFramesRendered++;
             if (numberOfFramesRendered == frameIndexToSkip) {
               frameSkippedCondition.open();
               return;
             }
-            super.renderOutputBufferV21(codec, index, presentationTimeUs, releaseTimeNs);
+            super.renderOutputBuffer(codec, index, presentationTimeUs, releaseTimeNs);
           }
         };
 

libraries/transformer/src/main/java/androidx/media3/transformer/EncoderUtil.java

@@ -313,7 +313,7 @@ public final class EncoderUtil {
     // Format must not include KEY_FRAME_RATE on API21.
     // https://developer.android.com/reference/android/media/MediaCodecList#findDecoderForFormat(android.media.MediaFormat)
     float frameRate = Format.NO_VALUE;
-    if (Util.SDK_INT == 21 && format.containsKey(MediaFormat.KEY_FRAME_RATE)) {
+    if (format.containsKey(MediaFormat.KEY_FRAME_RATE)) {
       try {
         frameRate = format.getFloat(MediaFormat.KEY_FRAME_RATE);
       } catch (ClassCastException e) {
@@ -328,9 +328,7 @@ public final class EncoderUtil {
             ? mediaCodecList.findDecoderForFormat(format)
             : mediaCodecList.findEncoderForFormat(format);
 
-    if (Util.SDK_INT == 21) {
     MediaFormatUtil.maybeSetInteger(format, MediaFormat.KEY_FRAME_RATE, round(frameRate));
-    }
     return mediaCodecName;
   }
 

testapps/controller/src/main/java/androidx/media3/testapp/controller/LaunchActivity.kt

@@ -19,7 +19,6 @@ import android.content.ComponentName
 import android.content.Context
 import android.content.Intent
 import android.media.session.MediaSessionManager as ActiveSessionManager
-import android.os.Build
 import android.os.Build.VERSION_CODES
 import android.os.Bundle
 import android.service.notification.NotificationListenerService
@@ -75,10 +74,7 @@ class LaunchActivity : AppCompatActivity() {
         }
       )
 
-    if (Build.VERSION.SDK_INT >= VERSION_CODES.LOLLIPOP) {
     activeSessionListener = ActiveSessionListener()
-    }
-
     mediaSessionApps = mediaAppListAdapter.addSection(R.string.media_app_header_media_service)
 
     val mediaAppsList: RecyclerView? = findViewById(R.id.app_list)
@@ -90,9 +86,7 @@ class LaunchActivity : AppCompatActivity() {
   override fun onStart() {
     super.onStart()
 
-    if (Build.VERSION.SDK_INT >= VERSION_CODES.LOLLIPOP) {
     activeSessionListener!!.onStart()
-    }
 
     // Finds apps that implement MediaSessionService, MediaLibraryService, or
     // MediaBrowserServiceCompat.
@@ -102,10 +96,8 @@ class LaunchActivity : AppCompatActivity() {
 
   override fun onStop() {
     super.onStop()
-    if (Build.VERSION.SDK_INT >= VERSION_CODES.LOLLIPOP) {
     activeSessionListener!!.onStop()
   }
-  }
 
   /**
    * Encapsulates the API 21+ functionality of looking for and observing updates to active media