JavaSE-11.3.3【接口案例-猫和狗】

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package day2.yubaby03.p3;   /* 3.4 接口案例-猫和狗  */   public class AnimalDemo {       public static void main(String[] args) {         Jumpping j = new Cat();         j.jump();           Animal a = new Cat();         a.setName("tom");         a.setAge(1);         System.out.println(a.getName() + "," + a.getAge());         a.eat(); //        a.jump(); //error         ((Cat) a).jump(); //ok         //or         Cat c = (Cat)a;         c.jump(); //ok           a = new Cat("sam", 2);         System.out.println(a.getName() + "," + a.getAge());         a.eat();         ((Cat) a).jump();           //从上述可以看出，通过接口得到的对象只能调用接口的成员方法，通过父类的只能调用父类的         //更常用的写法：（子类/实现类，既可以调用接口中的方法也可以调用父类中的）         Cat cat = new Cat();         cat.setName("it");         cat.setAge(3);         System.out.println(cat.getName() + "," + cat.getAge());         cat.eat();         cat.jump();     }   }

　　

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package day2.yubaby03.p3;   public abstract class Animal {       private String name;     private int age;       public Animal() {     }       public Animal(String name, int age) {         this.name = name;         this.age = age;     }       public void setName(String name) {         this.name = name;     }       public void setAge(int age) {         this.age = age;     }       public String getName() {         return name;     }       public int getAge() {         return age;     }       public abstract void eat(); }

　　

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package day2.yubaby03.p3;   public interface Jumpping {   //    public abstract void jump();       //或       void jump();   }

　　

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package day2.yubaby03.p3;   public class Cat extends Animal implements Jumpping{       public Cat() {     }       public Cat(String name, int age) {         super(name, age);     }       @Override     public void eat() { //重写自父类         System.out.println("猫猫吃饭了");     }       @Override     public void jump() { //重写自接口         System.out.println("猫猫跳高了");     } }

　　

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package day2.yubaby03.p3;   public class Dog extends Animal implements Jumpping{       public Dog() {     }       public Dog(String name, int age) {         super(name, age);     }       @Override     public void eat() {         System.out.println("狗狗吃饭了");     }       @Override     public void jump() {         System.out.println("狗狗跳高了");     } }