abstractclassAnimal{}classChickenextendsAnimalimplementsEdible{//implement是接上接口的關鍵字@Override//這裏系統會強制進行方法重寫,如果方法沒有寫或者寫錯了,會一直報錯public String howToEat(){return"Chicken: Fry it";}}classTigerextendsAnimal{}abstractclassFruitimplementsEdible{}classAppleextendsFruit{@Overridepublic String howToEat(){return"Apple: make apple cider";}}classOrangeextendsFruit{public String howToEat(){return"Orange: make orange juice";}}
List list =newArrayList();
list.add("Qiqi");
list.add("MiaoMiao");
list.add(100);for(int i=0; i<3; i++){
String a =(String)list.get(i);
System.out.println(a);}