public void testEquals() throws Exception {
    new ClassSanityTester()
        .setDistinctValues(Class.class, Color.class, Gender.class)
        .setDistinctValues(Enum.class, Color.BLUE, Color.RED)
        .forAllPublicStaticMethods(EnumMultisetFactory.class)
        .testEquals();
  }

  @J2ktIncompatible
  @GwtIncompatible // reflection
  public void testNulls() throws Exception {
    new NullPointerTester()