Comparateur Java comparant

1. Collections.sort(people,Comparator.comparing(Person::getLastName));

2.		Collections.sort(list,
		        Comparator.<Integer,Integer>comparing( i -> -grow[i])
		                  .thenComparing( i -> -plant[i]));

3.		Collections.sort(list,
		        Comparator.comparing( (Integer i) -> -grow[i])
		                  .thenComparing( i -> -plant[i]));

4.		Collections.sort(list,
		        Comparator.comparing( i -> -grow[(int)i])
		                  .thenComparing( i -> -plant[(int)i]));

Outstanding Ocelot