assertThrows(NullPointerException.class, () -> ImmutableBiMap.of(null, 1));

    assertThrows(NullPointerException.class, () -> ImmutableBiMap.of("one", 1, null, 2));
  }

  public void testOfNullValue() {
    assertThrows(NullPointerException.class, () -> ImmutableBiMap.of("one", null));

    assertThrows(NullPointerException.class, () -> ImmutableBiMap.of("one", 1, "two", null));
  }

    assertThrows(NullPointerException.class, () -> ImmutableSortedMap.of(n, 1));

    assertThrows(NullPointerException.class, () -> ImmutableSortedMap.of("one", 1, null, 2));
  }

  public void testOfNullValue() {
    assertThrows(NullPointerException.class, () -> ImmutableSortedMap.of("one", null));

    assertThrows(NullPointerException.class, () -> ImmutableSortedMap.of("one", 1, "two", null));
  }