Java 发红包实现

分析

 用户类

public class User {
    private String username; //定义用户变量
    private int money; //定于余额

    public User() {
    }

    public User(String username, int money) {
        this.username = username;
        this.money = money;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public int getMoney() {
        return money;
    }

    public void setMoney(int money) {
        this.money = money;
    }

    //创建show方法用来展示用户信息和余额
    public void show() {
        System.out.println(" " + username + " 我的余额：" + money);
    }
    public void show2(){
        System.out.print(" " + username + " 红包金额：" + money);
        System.out.println(" 我的余额"+money);
    }
    public void show1() {
        System.out.println(" " + username + " 剩余金额：" + money);
    }

}

 群主类

import java.util.ArrayList;

public class QunZhu extends User {
    //无参构造
    public QunZhu() {

    }

    //有参构造
    public QunZhu(String username, int money) {
        super(username, money);  //通过子类调用父类的构造方法
    }

    //发红包的自定义方法
    //分析 ；返回值     发红包的各个红包金额   Arraylist<Inter>
    //      方法名称   发红包s       end
    //      参数列表   红包大小，份数 int leftmoney, int count
    public ArrayList<Integer> send(int leftmoney, int count) {
        //定义一个变量用来存储群主的余额
        int money = super.getMoney();
        //判断发红包的金额是否小于余额
        if (leftmoney > money) {
            System.out.println("余额不足");
            return null;
        }
        //如果红包金额小于，就发红包来扣钱，重新设置余额
        setMoney(money - leftmoney);
        //定义一个集合，用来存储若干个红包的金额
        ArrayList<Integer> arrayList = new ArrayList<Integer>();
        //设定每份红包的金额
        int jiner = leftmoney / count;
        //如果红包分的不平均，取模取余
        int yushu = leftmoney % count;
        //循环遍历，将每份红包金额放到对数组对象中
        for (int i = 0; i < count - 1; i++) {
            //将金额添加到数组对象的元素中
            arrayList.add(jiner);
        }
        //将最后一个红包
        int last = jiner + yushu;
        //将最后一个红包添加到数组对象中
        arrayList.add(last);
        //返回值 集合
        return arrayList;
    }

}

 群员类

import java.util.ArrayList;
import java.util.Random;

public class QunYuan extends User {
    //无参构造
    public QunYuan() {
    }

    //有参构造
    public QunYuan(String username, int money) {
        super(username, money);  //调用父类的构造方法
    }

    //创建收红包或者打开红包的方法；
    //   返回值     没有返回值 用void
    //   方法名称   收红包或者打开红包的方法OpenHongBao
    //   参数列表   Arraylist<Inter> -----arraylist
    public void OpenHongBao(ArrayList<Integer> arrayList) {
        // 从多个红包当中随便抽取一个，给我自己。
        // 随机获取一个集合当中的索引编号
        //创建随机数对象index
        Random random = new Random();
        int index = random.nextInt(arrayList.size());
        //将红包金额给到自己
        int delta = arrayList.remove(index);
        //计算现有余额
        int money = super.getMoney();
        //将获得红包金额加到本来的余额里
        super.setMoney(money + delta);
    }

}

 测试类

import java.util.ArrayList;
import java.util.Scanner;

public class DemoTest {
    public static void main(String[] args) {
        //创建群主对象
        QunZhu qunZhu1 = new QunZhu("群主", 800);
        //创建群员对象
        QunYuan qunYuan1 = new QunYuan("小明", 0);
        QunYuan qunYuan2 = new QunYuan("小黄", 0);
        QunYuan qunYuan3 = new QunYuan("小里", 0);
        QunYuan qunYuan4 = new QunYuan("小三", 0);
        QunYuan qunYuan5 = new QunYuan("小蓝", 0);
        QunYuan qunYuan6 = new QunYuan("小紫", 0);
        QunYuan qunYuan7 = new QunYuan("小黑", 0);
        System.out.println("=================");
        qunZhu1.show();
        System.out.println("=================");
        qunYuan1.show();
        qunYuan2.show();
        qunYuan3.show();
        qunYuan4.show();
        qunYuan5.show();
        qunYuan6.show();
        qunYuan7.show();
        System.out.println("===============");
        //键盘输入
        System.out.println(qunZhu1.getUsername() + " 发红包了");
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入红包金额：");
        int money = scanner.nextInt();
        System.out.println("请输入红包个数：");
        int count = scanner.nextInt();
        if (count < 7) {
            System.out.println("输入错误");
            return;
        }
        //创建新的集合用来发红包
        ArrayList<Integer> redlist = qunZhu1.send(money, count);
        //群员打开红包
        System.out.println("=================");
        System.out.println("====红包抢完了====");
        qunYuan1.OpenHongBao(redlist);
        qunYuan2.OpenHongBao(redlist);
        qunYuan3.OpenHongBao(redlist);
        qunYuan4.OpenHongBao(redlist);
        qunYuan5.OpenHongBao(redlist);
        qunYuan6.OpenHongBao(redlist);
        qunYuan7.OpenHongBao(redlist);
        //展示金额
        System.out.println("=================");
        qunZhu1.show1();
        System.out.println("=================");
        qunYuan1.show2();
        qunYuan2.show2();
        qunYuan3.show2();
        qunYuan4.show2();
        qunYuan5.show2();
        qunYuan6.show2();
        qunYuan7.show2();
        System.out.println("=================");
    }
}