Java 动态绑定方法 多态

//多态存在的条件

//1.要有继承

//2.要有重写

//3.父类引用指向子类对象

package v39;

public class Test {

public static void main(String[] args){

Cat c = new Cat("catname","blue");

Dog d = new Dog("dogname","black");

Lady l1 = new Lady("l1",c);

Lady l2 = new Lady("l2",d);

l1.myPetEnjoy();//调用Cat的方法，方法存在code segment中

l2.myPetEnjoy();//调用Dog

的方法，方法存在codesegment中

}

}

class Lady{

private String name;

private Animal pet;

Lady(String name, Animal pet){

this.name = name;

this.pet = pet;

}

public void myPetEnjoy(){

pet.enjoy();

}

}

class Animal{

public String name;

Animal(String name){

this.name = name;

}

public void enjoy(){

System.out.println("叫声。。。");

}

}

class Bird extends Animal{

private String featherColor;

Bird(String n, String f){

super(n);

featherColor = f;

}

public void enjoy(){

System.out.println("鸟叫声。。。");

}

}

class Cat extends Animal{

public String eyeColor;

Cat(String name, String eyeColor){

super(name);

this.eyeColor = eyeColor;

}

public void enjoy(){

System.out.println("猫叫声喵。。。");

}

}

class Dog extends Animal{

public String furColor;

Dog(String name, String furColor){

super(name);

this.furColor = furColor;

}

public void enjoy(){

System.out.println("狗叫声。。。");

}

}