ImmutableMultiset.Builder<String> builder = ImmutableMultiset.builder();
    assertThrows(NullPointerException.class, () -> builder.setCount(null, 2));
  }

  public void testBuilderSetCountIllegal() {
    ImmutableMultiset.Builder<String> builder = ImmutableMultiset.builder();
    assertThrows(IllegalArgumentException.class, () -> builder.setCount("a", -2));
  }

  @J2ktIncompatible

    ImmutableMultiset.Builder<String> builder = ImmutableMultiset.builder();
    assertThrows(NullPointerException.class, () -> builder.setCount(null, 2));
  }

  public void testBuilderSetCountIllegal() {
    ImmutableMultiset.Builder<String> builder = ImmutableMultiset.builder();
    assertThrows(IllegalArgumentException.class, () -> builder.setCount("a", -2));
  }

  @J2ktIncompatible

        new ImmutableSortedMultiset.Builder<>(Ordering.natural().nullsFirst());
    assertThrows(NullPointerException.class, () -> builder.setCount(null, 2));
  }

  public void testBuilderSetCountIllegal() {
    ImmutableSortedMultiset.Builder<String> builder = ImmutableSortedMultiset.naturalOrder();
    assertThrows(IllegalArgumentException.class, () -> builder.setCount("a", -2));
  }