code: @Pure
  	public static <T> Iterator<T> filterNull(Iterator<T> unfiltered) {
  		return Iterators.filter(unfiltered, Predicates.notNull());
  	}
docs: Returns a new iterator filtering any null references.
  
  @param unfiltered
  the unfiltered iterator. May not be <code>null</code>.
  @return an unmodifiable iterator containing all elements of the original iterator without any <code>null</code>
  references. Never <code>null</code>.