Move @AudioFocusGain from C to AudioFocusManager and make it private

This is only used inside AudioFocusManager, it doesn't need to public.

Also mark it TYPE_USE and update the position to match.

#minor-release

PiperOrigin-RevId: 426407790

library/common/src/main/java/com/google/android/exoplayer2/C.java

@@ -471,34 +471,6 @@ public final class C {
   /** See {@link android.media.AudioAttributes#ALLOW_CAPTURE_BY_SYSTEM}. */
   public static final int ALLOW_CAPTURE_BY_SYSTEM = AudioAttributes.ALLOW_CAPTURE_BY_SYSTEM;
 
-  /**
-   * Audio focus types. One of {@link #AUDIOFOCUS_NONE}, {@link #AUDIOFOCUS_GAIN}, {@link
-   * #AUDIOFOCUS_GAIN_TRANSIENT}, {@link #AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK} or {@link
-   * #AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE}.
-   */
-  @Documented
-  @Retention(RetentionPolicy.SOURCE)
-  @IntDef({
-    AUDIOFOCUS_NONE,
-    AUDIOFOCUS_GAIN,
-    AUDIOFOCUS_GAIN_TRANSIENT,
-    AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK,
-    AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE
-  })
-  public @interface AudioFocusGain {}
-  /** @see AudioManager#AUDIOFOCUS_NONE */
-  public static final int AUDIOFOCUS_NONE = AudioManager.AUDIOFOCUS_NONE;
-  /** @see AudioManager#AUDIOFOCUS_GAIN */
-  public static final int AUDIOFOCUS_GAIN = AudioManager.AUDIOFOCUS_GAIN;
-  /** @see AudioManager#AUDIOFOCUS_GAIN_TRANSIENT */
-  public static final int AUDIOFOCUS_GAIN_TRANSIENT = AudioManager.AUDIOFOCUS_GAIN_TRANSIENT;
-  /** @see AudioManager#AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK */
-  public static final int AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK =
-      AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK;
-  /** @see AudioManager#AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE */
-  public static final int AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE =
-      AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE;
-
   /**
    * Flags which can apply to a buffer containing a media sample. Possible flag values are {@link
    * #BUFFER_FLAG_KEY_FRAME}, {@link #BUFFER_FLAG_END_OF_STREAM}, {@link #BUFFER_FLAG_LAST_SAMPLE},

library/core/src/main/java/com/google/android/exoplayer2/AudioFocusManager.java

@@ -95,6 +95,37 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
   /** Audio focus has been temporarily lost, but playback may continue with reduced volume. */
   private static final int AUDIO_FOCUS_STATE_LOSS_TRANSIENT_DUCK = 3;
 
+  /**
+   * Audio focus types. One of {@link #AUDIOFOCUS_NONE}, {@link #AUDIOFOCUS_GAIN}, {@link
+   * #AUDIOFOCUS_GAIN_TRANSIENT}, {@link #AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK} or {@link
+   * #AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE}.
+   */
+  @Documented
+  @Retention(RetentionPolicy.SOURCE)
+  @Target(TYPE_USE)
+  @IntDef({
+    AUDIOFOCUS_NONE,
+    AUDIOFOCUS_GAIN,
+    AUDIOFOCUS_GAIN_TRANSIENT,
+    AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK,
+    AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE
+  })
+  private @interface AudioFocusGain {}
+  /** @see AudioManager#AUDIOFOCUS_NONE */
+  @SuppressWarnings("InlinedApi")
+  private static final int AUDIOFOCUS_NONE = AudioManager.AUDIOFOCUS_NONE;
+  /** @see AudioManager#AUDIOFOCUS_GAIN */
+  private static final int AUDIOFOCUS_GAIN = AudioManager.AUDIOFOCUS_GAIN;
+  /** @see AudioManager#AUDIOFOCUS_GAIN_TRANSIENT */
+  private static final int AUDIOFOCUS_GAIN_TRANSIENT = AudioManager.AUDIOFOCUS_GAIN_TRANSIENT;
+  /** @see AudioManager#AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK */
+  private static final int AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK =
+      AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK;
+  /** @see AudioManager#AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE */
+  @SuppressWarnings("InlinedApi")
+  private static final int AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE =
+      AudioManager.AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE;
+
   private static final String TAG = "AudioFocusManager";
 
   private static final float VOLUME_MULTIPLIER_DUCK = 0.2f;
@@ -106,7 +137,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
   @Nullable private AudioAttributes audioAttributes;
 
   @AudioFocusState private int audioFocusState;
-  @C.AudioFocusGain private int focusGainToRequest;
+  private @AudioFocusGain int focusGainToRequest;
   private float volumeMultiplier = VOLUME_MULTIPLIER_DEFAULT;
 
   private @MonotonicNonNull AudioFocusRequest audioFocusRequest;
@@ -147,7 +178,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
       this.audioAttributes = audioAttributes;
       focusGainToRequest = convertAudioAttributesToFocusGain(audioAttributes);
       Assertions.checkArgument(
-          focusGainToRequest == C.AUDIOFOCUS_GAIN || focusGainToRequest == C.AUDIOFOCUS_NONE,
+          focusGainToRequest == AUDIOFOCUS_GAIN || focusGainToRequest == AUDIOFOCUS_NONE,
           "Automatic handling of audio focus is only available for USAGE_MEDIA and USAGE_GAME.");
     }
   }
@@ -185,7 +216,7 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
   }
 
   private boolean shouldAbandonAudioFocusIfHeld(@Player.State int playbackState) {
-    return playbackState == Player.STATE_IDLE || focusGainToRequest != C.AUDIOFOCUS_GAIN;
+    return playbackState == Player.STATE_IDLE || focusGainToRequest != AUDIOFOCUS_GAIN;
   }
 
   @PlayerCommand
@@ -266,12 +297,12 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
    * @param audioAttributes The audio attributes associated with this focus request.
    * @return The type of audio focus gain that should be requested.
    */
-  @C.AudioFocusGain
+  private static @AudioFocusGain int convertAudioAttributesToFocusGain(
-  private static int convertAudioAttributesToFocusGain(@Nullable AudioAttributes audioAttributes) {
+      @Nullable AudioAttributes audioAttributes) {
     if (audioAttributes == null) {
       // Don't handle audio focus. It may be either video only contents or developers
       // want to have more finer grained control. (e.g. adding audio focus listener)
-      return C.AUDIOFOCUS_NONE;
+      return AUDIOFOCUS_NONE;
     }
 
     switch (audioAttributes.usage) {
@@ -279,13 +310,13 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
         // during the phone call when AUDIOFOCUS_GAIN_TRANSIENT is requested for that.
         // Don't request audio focus here.
       case C.USAGE_VOICE_COMMUNICATION_SIGNALLING:
-        return C.AUDIOFOCUS_NONE;
+        return AUDIOFOCUS_NONE;
 
         // Javadoc says 'AUDIOFOCUS_GAIN: Examples of uses of this focus gain are for music
         // playback, for a game or a video player'
       case C.USAGE_GAME:
       case C.USAGE_MEDIA:
-        return C.AUDIOFOCUS_GAIN;
+        return AUDIOFOCUS_GAIN;
 
         // Special usages: USAGE_UNKNOWN shouldn't be used. Request audio focus to prevent
         // multiple media playback happen at the same time.
@@ -294,13 +325,13 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
             TAG,
             "Specify a proper usage in the audio attributes for audio focus"
                 + " handling. Using AUDIOFOCUS_GAIN by default.");
-        return C.AUDIOFOCUS_GAIN;
+        return AUDIOFOCUS_GAIN;
 
         // Javadoc says 'AUDIOFOCUS_GAIN_TRANSIENT: An example is for playing an alarm, or
         // during a VoIP call'
       case C.USAGE_ALARM:
       case C.USAGE_VOICE_COMMUNICATION:
-        return C.AUDIOFOCUS_GAIN_TRANSIENT;
+        return AUDIOFOCUS_GAIN_TRANSIENT;
 
         // Javadoc says 'AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK: Examples are when playing
         // driving directions or notifications'
@@ -312,28 +343,28 @@ import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
       case C.USAGE_NOTIFICATION_COMMUNICATION_REQUEST:
       case C.USAGE_NOTIFICATION_EVENT:
       case C.USAGE_NOTIFICATION_RINGTONE:
-        return C.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK;
+        return AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK;
 
         // Javadoc says 'AUDIOFOCUS_GAIN_EXCLUSIVE: This is typically used if you are doing
         // audio recording or speech recognition'.
         // Assistant is considered as both recording and notifying developer
       case C.USAGE_ASSISTANT:
         if (Util.SDK_INT >= 19) {
-          return C.AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE;
+          return AUDIOFOCUS_GAIN_TRANSIENT_EXCLUSIVE;
         } else {
-          return C.AUDIOFOCUS_GAIN_TRANSIENT;
+          return AUDIOFOCUS_GAIN_TRANSIENT;
         }
 
         // Special usages:
       case C.USAGE_ASSISTANCE_ACCESSIBILITY:
         if (audioAttributes.contentType == C.CONTENT_TYPE_SPEECH) {
           // Voice shouldn't be interrupted by other playback.
-          return C.AUDIOFOCUS_GAIN_TRANSIENT;
+          return AUDIOFOCUS_GAIN_TRANSIENT;
         }
-        return C.AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK;
+        return AUDIOFOCUS_GAIN_TRANSIENT_MAY_DUCK;
       default:
         Log.w(TAG, "Unidentified audio usage: " + audioAttributes.usage);
-        return C.AUDIOFOCUS_NONE;
+        return AUDIOFOCUS_NONE;
     }
   }