Use a shared keyForField implementation in track selection parameters

The current setup with distinct, private `keyForField` implementations,
leaves open the (theoretical) possibility of a clash in the `Bundle`
keys used by the superclass and subclass. This change brings
consistency with our only other extensible `Bundleable` type
(`PlaybackException`).

#minor-release

PiperOrigin-RevId: 453385875

libraries/common/src/main/java/androidx/media3/common/TrackSelectionParameters.java

@@ -24,7 +24,6 @@ import android.graphics.Point;
 import android.os.Bundle;
 import android.os.Looper;
 import android.view.accessibility.CaptioningManager;
-import androidx.annotation.IntDef;
 import androidx.annotation.Nullable;
 import androidx.annotation.RequiresApi;
 import androidx.media3.common.util.BundleableUtil;
@@ -34,9 +33,6 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.primitives.Ints;
-import java.lang.annotation.Documented;
-import java.lang.annotation.Retention;
-import java.lang.annotation.RetentionPolicy;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Iterator;
@@ -1073,42 +1069,6 @@ public class TrackSelectionParameters implements Bundleable {
 
   // Bundleable implementation
 
-  @Documented
-  @Retention(RetentionPolicy.SOURCE)
-  @IntDef({
-    // Video
-    FIELD_MAX_VIDEO_WIDTH,
-    FIELD_MAX_VIDEO_HEIGHT,
-    FIELD_MAX_VIDEO_FRAMERATE,
-    FIELD_MAX_VIDEO_BITRATE,
-    FIELD_MIN_VIDEO_WIDTH,
-    FIELD_MIN_VIDEO_HEIGHT,
-    FIELD_MIN_VIDEO_FRAMERATE,
-    FIELD_MIN_VIDEO_BITRATE,
-    FIELD_VIEWPORT_WIDTH,
-    FIELD_VIEWPORT_HEIGHT,
-    FIELD_VIEWPORT_ORIENTATION_MAY_CHANGE,
-    FIELD_PREFERRED_VIDEO_MIMETYPES,
-    FIELD_PREFERRED_VIDEO_ROLE_FLAGS,
-    // Audio
-    FIELD_PREFERRED_AUDIO_LANGUAGES,
-    FIELD_PREFERRED_AUDIO_ROLE_FLAGS,
-    FIELD_MAX_AUDIO_CHANNEL_COUNT,
-    FIELD_MAX_AUDIO_BITRATE,
-    FIELD_PREFERRED_AUDIO_MIME_TYPES,
-    // Text
-    FIELD_PREFERRED_TEXT_LANGUAGES,
-    FIELD_PREFERRED_TEXT_ROLE_FLAGS,
-    FIELD_IGNORED_TEXT_SELECTION_FLAGS,
-    FIELD_SELECT_UNDETERMINED_TEXT_LANGUAGE,
-    // General
-    FIELD_FORCE_LOWEST_BITRATE,
-    FIELD_FORCE_HIGHEST_SUPPORTED_BITRATE,
-    FIELD_SELECTION_OVERRIDES,
-    FIELD_DISABLED_TRACK_TYPE,
-  })
-  private @interface FieldNumber {}
-
   private static final int FIELD_PREFERRED_AUDIO_LANGUAGES = 1;
   private static final int FIELD_PREFERRED_AUDIO_ROLE_FLAGS = 2;
   private static final int FIELD_PREFERRED_TEXT_LANGUAGES = 3;
@@ -1136,6 +1096,15 @@ public class TrackSelectionParameters implements Bundleable {
   private static final int FIELD_PREFERRED_VIDEO_ROLE_FLAGS = 25;
   private static final int FIELD_IGNORED_TEXT_SELECTION_FLAGS = 26;
 
+  /**
+   * Defines a minimum field ID value for subclasses to use when implementing {@link #toBundle()}
+   * and {@link Bundleable.Creator}.
+   *
+   * <p>Subclasses should obtain keys for their {@link Bundle} representation by applying a
+   * non-negative offset on this constant and passing the result to {@link #keyForField(int)}.
+   */
+  @UnstableApi protected static final int FIELD_CUSTOM_ID_BASE = 1000;
+
   @Override
   public Bundle toBundle() {
     Bundle bundle = new Bundle();
@@ -1197,7 +1166,15 @@ public class TrackSelectionParameters implements Bundleable {
   public static final Creator<TrackSelectionParameters> CREATOR =
       TrackSelectionParameters::fromBundle;
 
-  private static String keyForField(@FieldNumber int field) {
+  /**
+   * Converts the given field number to a string which can be used as a field key when implementing
+   * {@link #toBundle()} and {@link Bundleable.Creator}.
+   *
+   * <p>Subclasses should use {@code field} values greater than or equal to {@link
+   * #FIELD_CUSTOM_ID_BASE}.
+   */
+  @UnstableApi
+  protected static String keyForField(int field) {
     return Integer.toString(field, Character.MAX_RADIX);
   }
 }

libraries/exoplayer/src/main/java/androidx/media3/exoplayer/trackselection/DefaultTrackSelector.java

@@ -1688,50 +1688,30 @@ public class DefaultTrackSelector extends MappingTrackSelector {
 
     // Bundleable implementation.
 
-    @Documented
+    private static final int FIELD_EXCEED_VIDEO_CONSTRAINTS_IF_NECESSARY = FIELD_CUSTOM_ID_BASE;
-    @Retention(RetentionPolicy.SOURCE)
+    private static final int FIELD_ALLOW_VIDEO_MIXED_MIME_TYPE_ADAPTIVENESS =
-    @Target(TYPE_USE)
+        FIELD_CUSTOM_ID_BASE + 1;
-    @IntDef({
+    private static final int FIELD_ALLOW_VIDEO_NON_SEAMLESS_ADAPTIVENESS = FIELD_CUSTOM_ID_BASE + 2;
-      // Video
+    private static final int FIELD_EXCEED_AUDIO_CONSTRAINTS_IF_NCESSARY = FIELD_CUSTOM_ID_BASE + 3;
-      FIELD_EXCEED_VIDEO_CONSTRAINTS_IF_NECESSARY,
+    private static final int FIELD_ALLOW_AUDIO_MIXED_MIME_TYPE_ADAPTIVENESS =
-      FIELD_ALLOW_VIDEO_MIXED_MIME_TYPE_ADAPTIVENESS,
+        FIELD_CUSTOM_ID_BASE + 4;
-      FIELD_ALLOW_VIDEO_NON_SEAMLESS_ADAPTIVENESS,
+    private static final int FIELD_ALLOW_AUDIO_MIXED_SAMPLE_RATE_ADAPTIVENESS =
-      FIELD_ALLOW_VIDEO_MIXED_DECODER_SUPPORT_ADAPTIVENESS,
+        FIELD_CUSTOM_ID_BASE + 5;
-      // Audio
+    private static final int FIELD_ALLOW_AUDIO_MIXED_CHANNEL_COUNT_ADAPTIVENESS =
-      FIELD_EXCEED_AUDIO_CONSTRAINTS_IF_NCESSARY,
+        FIELD_CUSTOM_ID_BASE + 6;
-      FIELD_ALLOW_AUDIO_MIXED_MIME_TYPE_ADAPTIVENESS,
+    private static final int FIELD_EXCEED_RENDERER_CAPABILITIES_IF_NECESSARY =
-      FIELD_ALLOW_AUDIO_MIXED_SAMPLE_RATE_ADAPTIVENESS,
+        FIELD_CUSTOM_ID_BASE + 7;
-      FIELD_ALLOW_AUDIO_MIXED_CHANNEL_COUNT_ADAPTIVENESS,
+    private static final int FIELD_TUNNELING_ENABLED = FIELD_CUSTOM_ID_BASE + 8;
-      FIELD_ALLOW_AUDIO_MIXED_DECODER_SUPPORT_ADAPTIVENESS,
+    private static final int FIELD_ALLOW_MULTIPLE_ADAPTIVE_SELECTIONS = FIELD_CUSTOM_ID_BASE + 9;
-      // General
+    private static final int FIELD_SELECTION_OVERRIDES_RENDERER_INDICES = FIELD_CUSTOM_ID_BASE + 10;
-      FIELD_EXCEED_RENDERER_CAPABILITIES_IF_NECESSARY,
+    private static final int FIELD_SELECTION_OVERRIDES_TRACK_GROUP_ARRAYS =
-      FIELD_TUNNELING_ENABLED,
+        FIELD_CUSTOM_ID_BASE + 11;
-      FIELD_ALLOW_MULTIPLE_ADAPTIVE_SELECTIONS,
+    private static final int FIELD_SELECTION_OVERRIDES = FIELD_CUSTOM_ID_BASE + 12;
-      // Overrides
+    private static final int FIELD_RENDERER_DISABLED_INDICES = FIELD_CUSTOM_ID_BASE + 13;
-      FIELD_SELECTION_OVERRIDES_RENDERER_INDICES,
+    private static final int FIELD_ALLOW_VIDEO_MIXED_DECODER_SUPPORT_ADAPTIVENESS =
-      FIELD_SELECTION_OVERRIDES_TRACK_GROUP_ARRAYS,
+        FIELD_CUSTOM_ID_BASE + 14;
-      FIELD_SELECTION_OVERRIDES,
+    private static final int FIELD_ALLOW_AUDIO_MIXED_DECODER_SUPPORT_ADAPTIVENESS =
-      FIELD_RENDERER_DISABLED_INDICES,
+        FIELD_CUSTOM_ID_BASE + 15;
-    })
-    private @interface FieldNumber {}
-
-    // Start at 1000 to avoid conflict with the base class fields.
-    private static final int FIELD_EXCEED_VIDEO_CONSTRAINTS_IF_NECESSARY = 1000;
-    private static final int FIELD_ALLOW_VIDEO_MIXED_MIME_TYPE_ADAPTIVENESS = 1001;
-    private static final int FIELD_ALLOW_VIDEO_NON_SEAMLESS_ADAPTIVENESS = 1002;
-    private static final int FIELD_EXCEED_AUDIO_CONSTRAINTS_IF_NCESSARY = 1003;
-    private static final int FIELD_ALLOW_AUDIO_MIXED_MIME_TYPE_ADAPTIVENESS = 1004;
-    private static final int FIELD_ALLOW_AUDIO_MIXED_SAMPLE_RATE_ADAPTIVENESS = 1005;
-    private static final int FIELD_ALLOW_AUDIO_MIXED_CHANNEL_COUNT_ADAPTIVENESS = 1006;
-    private static final int FIELD_EXCEED_RENDERER_CAPABILITIES_IF_NECESSARY = 1007;
-    private static final int FIELD_TUNNELING_ENABLED = 1008;
-    private static final int FIELD_ALLOW_MULTIPLE_ADAPTIVE_SELECTIONS = 1009;
-    private static final int FIELD_SELECTION_OVERRIDES_RENDERER_INDICES = 1010;
-    private static final int FIELD_SELECTION_OVERRIDES_TRACK_GROUP_ARRAYS = 1011;
-    private static final int FIELD_SELECTION_OVERRIDES = 1012;
-    private static final int FIELD_RENDERER_DISABLED_INDICES = 1013;
-    private static final int FIELD_ALLOW_VIDEO_MIXED_DECODER_SUPPORT_ADAPTIVENESS = 1014;
-    private static final int FIELD_ALLOW_AUDIO_MIXED_DECODER_SUPPORT_ADAPTIVENESS = 1015;
 
     @Override
     public Bundle toBundle() {
@@ -1787,10 +1767,6 @@ public class DefaultTrackSelector extends MappingTrackSelector {
     public static final Creator<Parameters> CREATOR =
         bundle -> new Parameters.Builder(bundle).build();
 
-    private static String keyForField(@FieldNumber int field) {
-      return Integer.toString(field, Character.MAX_RADIX);
-    }
-
     /**
      * Bundles selection overrides in 3 arrays of equal length. Each triplet of matching indices is:
      * the selection override (stored in a sparse array as they can be null), the trackGroupArray of