}

  public void testCreateEmptyWithClass() {
    Multiset<Color> ms = EnumMultiset.create(ImmutableList.<Color>of(), Color.class);
    ms.add(Color.RED);
  }

  public void testCreateEmptyWithoutClassFails() {
    assertThrows(
        IllegalArgumentException.class, () -> EnumMultiset.create(ImmutableList.<Color>of()));
  }

  public void testToString() {