public void isNotIn(@Nullable Iterable<?> iterable) {
    checkNotNull(iterable);
    if (Iterables.contains(iterable, actual)) {
      failWithActual("expected not to be any of", iterable);
    }
  }
@Test
  public void isNotIn() {
    assertThat("x").isNotIn(oneShotIterable("a", "b", "c"));
  }