day10 零钱通系统

模拟零钱通系统。
主要功能有零钱明细、入账、消费和退出。

package com.yusa.smallchanges;

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

public class SmallChangeSys {
    public int key;
    public double balance;
    public boolean loop =true;
    public Scanner scanner = new Scanner(System.in);
    public String detilInfo="====零钱通明细====";
    // 显示菜单
    public static void main(String[] args) {
        SmallChangeSys smallChangeSys = new SmallChangeSys();
        smallChangeSys.loopMenu();
    }
    //循环菜单
    public void loopMenu(){
        while (true) {
            printMenu();
            key = scanner.nextInt();
            if(key==1){
                printDetil();
            }
            if(key==2){
                income();
            }
            if(key==3){
                cost();
            }
            if (key == 4) {
                quit();
            }
            if (!loop){
                break;
            }
        }
    }
    public void printMenu(){
        System.out.println("====零钱通菜单====");
        System.out.println("\t1.零钱通明细");
        System.out.println("\t2.收益入账");
        System.out.println("\t3.消费");
        System.out.println("\t4.退出");
        System.out.println("请选择：");
    }
    //零钱明细
    public void printDetil(){
        System.out.println(detilInfo);
    }
    //入账
    public void income(){
        System.out.println("请输入入账金额：");
        double inco=scanner.nextDouble();
        while (inco<0){
            System.out.println("入账金额有误，请重新输入：");
            inco=scanner.nextDouble();
        }
        balance+=inco;
        Date date = new Date();
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm");
        detilInfo+="\n收益入账\t+"+inco+"\t"+simpleDateFormat.format(date)   + "\t余额："+balance;
        System.out.println("入账成功");
    }
    //消费
    public void cost(){
        System.out.println("请输入消费金额：");
        double inco=scanner.nextDouble();
        while (inco<0|| inco>balance){
            System.out.println("消费金额有误，请重新输入：");
            inco=scanner.nextDouble();
        }
        System.out.println("请输入消费事项：");
        String costthings=scanner.next();
        balance-=inco;
        Date date = new Date();
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd hh:mm");
        detilInfo+="\n"+costthings+"\t-"+inco+"\t"+simpleDateFormat.format(date)   + "\t余额："+balance;
        System.out.println("消费成功");}
    //退出
    public void quit(){
        System.out.println("是否退出?y/n");
        boolean quitFlag=false;
        while(true){
            String s= scanner.next();
            for (int i = 0; i < s.length(); i++) {
                if(s.charAt(i)=='y'){
                    loop=false;
                    quitFlag=true;
                    System.out.println("已退出");
                    break;
                }
                else if (s.charAt(i)=='n'){
                    quitFlag=true;
                    System.out.println("已取消退出");
                    break;
                }
            }
            if(quitFlag){
                break;
            }
        }
    }
}