code: public static <E> HashSet<E> newHashSet(Iterable<? extends E> elements) {
  		return (elements instanceof Collection) ? new HashSet<E>((Collection<? extends E>)elements)
  				: newHashSet(elements.iterator());
  	}
docs: Creates a <i>mutable</i> {@code HashSet} instance containing the given elements in unspecified order.
  
  @param elements the elements that the set should contain
  @return a new {@code HashSet} containing those elements (minus duplicates)