code: public static Iterable<GraphObject> map(final Iterable<Object> src) {
  
  		return Iterables.map((Object t) -> {
  
  			if (t instanceof GraphObject) {
  				return (GraphObject)t;
  			}
  
  			if (t instanceof Map) {
  
  				return Function.toGraphObjectMap((Map)t);
  			}
  
  			throw new ClassCastException(t.getClass() + " cannot be cast to " + GraphObject.class.getName());
  
  		}, src);
  
  	}
docs: ----- public static methods -----