*
 * @author Mike Bostock
 * @since 2.0
 */
@GwtCompatible
@J2ktIncompatible
public final class EnumBiMap<K extends Enum<K>, V extends Enum<V>> extends AbstractBiMap<K, V> {
  /*
   * J2CL's EnumMap does not need the Class instance, so we can use Object.class instead. (Or we
   * could use null, but that messes with our nullness checking, including under J2KT. We could

 *
 * @author Mike Bostock
 * @since 2.0
 */
@GwtCompatible
@J2ktIncompatible
public final class EnumHashBiMap<K extends Enum<K>, V extends @Nullable Object>
    extends AbstractBiMap<K, V> {
  transient Class<K> keyTypeOrObjectUnderJ2cl;

  /**
   * Returns a new, empty {@code EnumHashBiMap} using the specified key type.
   *
   * @param keyType the key type
   */

   * as implementation details.
   *
   * <p>Since the bimap is immutable, ImmutableBiMap doesn't require special logic for keeping the
   * bimap and its inverse in sync during serialization, the way AbstractBiMap does.
   */
  @J2ktIncompatible // serialization
  private static final class SerializedForm<K, V> extends ImmutableMap.SerializedForm<K, V> {
    SerializedForm(ImmutableBiMap<K, V> bimap) {
      super(bimap);