案例分析

基于下面的代码

Animal.java
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public class Animal {    public int age;    public void eat() {        System.out.println("Animal eat()");    }}

Person.java
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public class Person {    public int age;    public double balance;    public void eat() {        System.out.println("Person eat()");    }    public void work() {        System.out.println("Person work()");    }}

Dog.java
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public class Dog {    public int age;    public void eat() {        System.out.println("Dog eat()");    }    public void bark() {        System.out.println("Dog bark()");    }}

Zoo.java
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public class Zoo {    public static void main(String[] args) {        new Zoo().run();    }     public void run() {        Dog dog = new Dog();        Person person = new Person();        dog.eat();        person.eat();    }}

问题

age 和 eat 在 Person / Dog / Animal 中都有