模拟发红包案例-Java

模拟发红包

  • 结构分析

代码

  • User类
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public class User {
    private String name;
    private double money;

    public User() {
    }

    public User(String name, double money) {
        this.name = name;
        this.money = money;
    }

    //显示信息
    public void show() {
        System.out.println("我叫：" + this.name + "剩余金额：" + this.money);
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public double getMoney() {
        return money;
    }

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

  • Manager类
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public class Manager extends User {
    public Manager() {
    }

    public Manager(String name, int money) {
        super(name, money);
    }

    //发平均红包
    public ArrayList<Double> send(double totoalMoney, int count) {
        /**红包金额平等
         //存放若干红包金额
         ArrayList<Integer> integerArrayList = new ArrayList<>();
         if (totoalMoney > super.getMoney()) {
         System.out.println("余额不足！");
         return integerArrayList;
         }
         int avg = totoalMoney / count;//均分
         int mod = totoalMoney % count;//余数
         //修改余额
         super.setMoney(super.getMoney() - totoalMoney);
         for (int i = 0; i < count - 1; i++) {
         integerArrayList.add(avg);
         }
         //最后一个人分红包
         int last = mod + avg;
         integerArrayList.add(last);
         return integerArrayList;
         **/

        //随机分配金额，最少一分钱。最多不超过剩下金额平均值的2倍
        //公式：0.01 + random.nextInt(leftMoney /leftCount * 2)

        Random r = new Random();
        //totoalMoney最多两位小数，计算完强转为int
        int leftMoney = (int) (totoalMoney* 100);//转换成分计算

        int leftCount = count;
        int max = leftMoney / leftCount * 2;
        ArrayList<Double> list = new ArrayList<>();
        //随机发前count-1个
        for (int i = 0; i < count - 1; i++) {
            int money = r.nextInt(leftMoney / leftCount * 2) + 1;
            list.add((double) money / 100);
            leftMoney -= money;
            leftCount--;
        }
        list.add((double) leftMoney / 100);
        super.setMoney(super.getMoney()-totoalMoney);
        return list;
    }

}

  • Member类
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public class Member extends User {
    public Member() {
    }

    public Member(String name, int money) {
        super(name, money);
    }

    public void receive(ArrayList<Double> list) {
        //随机获取一个集合中的索引编号
        int index = new Random().nextInt(list.size());
        //根据索引，从集合中删除，得到被删除的红包金额
        double delta = list.remove(index);
        //加法，重新设置剩余金额
        super.setMoney(super.getMoney() + delta);
    }
}
  • 主类
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public static void main(String[] args) {
       Manager manager = new Manager("hxx", 100);
       Member one = new Member("qzy", 0);
       Member two = new Member("zyx", 0);
       Member third = new Member("wn", 0);
       Member four = new Member("hxs",0);
       //发红包
       ArrayList<Double> list = manager.send(3.1, 4);
       //分红包
       one.receive(list);
       two.receive(list);
       third.receive(list);
       four.receive(list);

       manager.show();

       one.show();
       two.show();
       third.show();
       four.show();
}
  • 运行结果
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我叫：hxx剩余金额：96.9
我叫：qzy剩余金额：0.56
我叫：zyx剩余金额：0.66
我叫：wn剩余金额：0.67
我叫：hxs剩余金额：1.21