1. Collections.sort(people,Comparator.comparing(Person::getLastName)); 2. Collections.sort(list, Comparator.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]));