补充上次的将父类作为方法的返回类型

Posted 2022-04-28 lev1

宠物类

package cn.Animal;

public class Animal 
    public void play() 

狗类

package cn.Animal;

public class Dog extends Animal 
    public void play() 
        System.out.println("狗在玩蛇");
    

猫类

package cn.Animal;

public class Cat extends Animal 
    public void play() 
        System.out.println("猫咪在玩球");
    

鸭子类

package cn.Animal;

public class Duck extends Animal 
    public void play() 
        System.out.println("鸭子在玩水");
    

主人类

package cn.Animal;
//主人类
public class Host 
    //动物在玩不同的游戏,将父类作为方法的返回类型
    public Animal toPlay(String type) 
        Animal animal = null;
        if(type.equals("cat")) 
            animal =  new Cat();
        else if(type.equals("dog")) 
            animal = new Dog();
        else 
            animal =  new Duck();
        
        return animal;
    
    

测试类

package cn.Animal;

public class Test 
        public static void main(String[] args) 
            Host host = new Host();
            Animal animal = host.toPlay("dog");
            animal.play();
        

结果