继承练习：发红包案例实现（群主发红包 群成员接收红包）

//Userpackage ExtendTest;/*群主发红包的功能实现（用到Extend）：父类：User（用户）属性：name（姓名），money（总金额）方法：无参构造和含参数（name，money）构造，show方法显示totalmoney内容子类：Manager（群主）继承User的属性和构造方法自己的方法Send()，参数列表为（sendmoney钱包金额，count人数），返回值类型：Arraylist（list1）判断发送金额 > 余额，返回空集合，输出：余额不足！发送金额 <= 余额 则余额=余额 - 发送金额子类：Member（成员）继承User的属性和构造方法自己的方法receive(),返回值类型：void或者int（返回成员的余额）参数列表Arraylist<Integer>,随机获得集合Arraylist中的任意一个红包（随机数Random）*/public class User {//父类：用户private String name;private int money;public User() {}public User(String name, int money) {this.name = name;this.money = money;}public void show(){System.out.println("我叫"+name+",我有多少钱："+money);}public String getName() {return name;}public void setName(String name) {this.name = name;}public int getmoney() {return money;}public void setmoney(int money) {this.money = money;}}//Managerpackage ExtendTest;import java.util.ArrayList;public class Manager extends User {//子类：群主public Manager() {// 有个默认super();方法}public Manager(String name, int money) {super(name, money);}public ArrayList<Integer> send(int sendmoney,int count){ArrayList<Integer> list1 = new ArrayList<Integer>();int leftmoney = super.getmoney();if (leftmoney < sendmoney){System.out.println("余额不足！");return list1;}super.setmoney(leftmoney - sendmoney);int avg = sendmoney/count;//均分count人后的每个红包的金额int mod = sendmoney%count;//红包未除尽的剩余金额（计入最后一个红包发送）for (int i = 0; i < count - 1; i++) {list1.add(avg);}int sum = avg + mod;list1.add(sum);return list1;}}//Memberpackage ExtendTest;import java.util.ArrayList;import java.util.Random;public class Member extends User{//子类：普通成员public Member() {// 默认含有一个super()}public Member(String name, int totalmoney) {super(name, totalmoney);}public int receive(ArrayList<Integer> list){int index = new Random().nextInt(list.size());int del = list.remove(index);super.setmoney(super.getmoney() + del);//现在余额=余额+红包金额return super.getmoney();}}//测试主类package ExtendTest;import java.util.ArrayList;public class RedPackageTest {public static void main(String[] args) {Manager manager = new Manager("群主",100);Member one = new Member("M1",10);Member two = new Member("M2",0);Member three = new Member("M3",5);manager.show();ArrayList<Integer> list=manager.send(20,3);manager.show();one.show();two.show();three.show();int onemoney = one.receive(list);System.out.println("M1's money:"+onemoney);System.out.println("M2's money:"+two.receive(list));System.out.println("M3's money:"+three.receive(list));}}