code: public static <T> boolean elementIsNotContainedInList(T element, Collection<T> values) {
      if (element != null && values != null) {
        return !values.contains(element);
      }
      else {
        return false;
      }
    }
docs: Checks if the element is not contained within the list of values. If the element, or the list are null then true is returned.
  
  @param element to check
  @param values to check in
  @param <T> the type of the element
  @return {@code true} if the element and values are not {@code null} and the values does not contain the element, {@code false} otherwise