Week 9 Examples - JShell

import java.util.*;
ls1 = (ArrayList)ls2;
ls1 instanceof ArrayList;
ls1 instanceof List;
ls1 instanceof LinkedList;
ls.add(5);
ls.add("hi");
String x = (String)ls.get(0);
String y = ((Integer)ls.get(0)).toString();
ls = List.of(5, "hi");
class Animal {}
class Antelope extends Animal {}
l.eat(a);
class Turtle extends Animal {}
var t = new Turtle();
l.eat(t);
class Lion extends Animal implements Predator{
  public void eat(Animal food) {
    System.out.println("yum");
  }
}
var l = new Lion();
l.eat(l);
class Ant extends Animal{}
class AntEater extends Animal implements Predator<Ant> {
  public void eat(Ant food) {
    System.out.println("bloodoadododod");
  }
}
AntEater a = new AntEater();
a.eat(flick);
l.eat(flick);
interface Predator<FOOD extends Animal> {
  void eat(FOOD food);
  default void eatAll(List<FOOD> foods) {
    for(var food : foods) eat(food);
  }
}
var lion = new Lion();
var flick = new Ant();
var simba = new Lion();
var al = new AntEater();
simba.eatAll(foods);
var anteaterFoods = List.of(flick);
al.eatAll(anteaterFoods);
List<Ant> foods = List.of(flick);
simba.eatAll(anteaterFoods);
List<String> ls = null;
List<String> ls1 = null;
List<Object> ls2 = null;
List<? extends Object> ls3 = null;
ls = new ArrayList<String>();
ls1 = new ArrayList<String>();
ls3 = new ArrayList<String>();
interface Zookeeper {
// feeds food to animal
public void feedingTime(Object animal, Object food);
// returns a sublists of animals that can live together peacefully
public List<Object> safeSubset(List<Object> animals);
}