package exp4; abstract class Animal{ String name; int age; public Animal(){}; public Animal(String name, int age){ this.name = name; this.age = age; } abstract void eat(); abstract void show(); } class Cat extends Animal{ public Cat(){}; public Cat(String name, int age){ super(name, age); } void eat(){ System.out.println("猫吃鱼"); } void show(){ System.out.println(this.name+","+this.age); } } class Dog extends Animal{ public Dog(){}; public Dog(String name, int age){ super(name, age); } void eat(){ System.out.println("狗吃肉"); } void show(){ System.out.println(this.name+","+this.age); } } public class AnimalTool { public static void main(String[] args){ Animal a = new Cat(); Animal b = new Dog("旺财", 3); a.name = "Tom"; a.age = 999; a.show(); b.show(); a.eat(); b.eat(); } }