return (Map<K, Collection<V>>) new EnumMap<K0, Collection<V>>(keyClass);
      }
    };
  }

  private static final class ArrayListSupplier<V extends @Nullable Object>
      implements Supplier<List<V>>, Serializable {
    private final int expectedValuesPerKey;

    ArrayListSupplier(int expectedValuesPerKey) {
      this.expectedValuesPerKey = checkNonnegative(expectedValuesPerKey, "expectedValuesPerKey");
    }

        return (Map<K, Collection<V>>) new EnumMap<K0, Collection<V>>(keyClass);
      }
    };
  }

  private static final class ArrayListSupplier<V extends @Nullable Object>
      implements Supplier<List<V>>, Serializable {
    private final int expectedValuesPerKey;

    ArrayListSupplier(int expectedValuesPerKey) {
      this.expectedValuesPerKey = checkNonnegative(expectedValuesPerKey, "expectedValuesPerKey");
    }