Java零钱通

简单零钱通

调取mainMenu方法即可

package com.hspedu.smallChangeSys;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;

public class smallChangeOOP {
    boolean loop = true;
    String key = "";
    Scanner scanner = new Scanner(System.in);

    //2 完成零钱通明细1.可以把收益入账保存到数组 2.可以使用对象 3.简单的可以使用String拼接
    String details = "--------------零钱通明细--------------";

    //3 完成收益入账 完成功能驱动增加新的变化和代码
    //定义新的变量()
    double money = 0;
    double balance = 0;
    Date date = null;
    SimpleDateFormat sdf = new SimpleDateFormat("yyyy, MM, dd, HH, mm");//用于日期格式化

    //4.消费
    //定义
    String note = "";
    public void mainMenu(){

        do {
            System.out.println("n==========零钱通菜单==========");
            System.out.println("tt1 零钱明细");
            System.out.println("tt2 收益入账");
            System.out.println("tt3 消费");
            System.out.println("tt4 退   出");

            System.out.print("请选择（1-4）:");
            key = scanner.next();

            //使用switch分支结构
            switch (key) {
                case "1":
                    System.out.println(details);
                    break;
                case "2":
                    this.income();
                    break;
                case "3":
                    this.consume();
                    break;
                case "4":
                   this.exit();
                   break;
                default:
                    System.out.println("选择不再范围内，请重新输入");
                    break;
            }
        } while (loop);
        System.out.println("------已退出零钱通------");
    }
    public void income(){
        System.out.print("入账金额:");
        money = scanner.nextDouble();
        if (money <= 0) {
            System.out.println("请重新输入金额，应大于0");
            return;
        }
        balance += money;

        date = new Date();
        details += "n入账+" + money + "t" + sdf.format(date) + "t" + balance;
        System.out.println("入账：" + money);
    }
    public void consume(){
        System.out.println("消费金额：");
        money = scanner.nextDouble();
        if (money <= 0 || money >= balance) {//过关斩将校验，一道一道设置条件障碍
            System.out.println("请重新输入,消费金额应在（0-" +balance + "）之间t");
            return;
        }

        System.out.println("消费说明：");
        note = scanner.next();
        balance -= money;
        details += "n" + note + "t-" + money + "t" + sdf.format(date) + "t" + balance;
        System.out.println("消费：" + money);
    }
    public void exit(){
        String choice = "";
        while (true) {
            System.out.println("是否选择退出 y/n");
            choice = scanner.next();
            if ("y".equals(choice) || "n".equals((choice))) {
                break;
            }
        }
        if (choice.equals("y")) {
            loop = false;
        }
    }
}