需求分析

首先ATM银行系统包括两个基础大功能：开户和登陆账户（当然在系统中没有一个账户时不能登录，需要先开户）。

一名用户有6项基本信息描述：姓名、性别、银行卡号、银行卡密码、账户余额、取款限额。

在登录账户后又有7项功能：查询账户信息、存款、取款、转账、修改密码、退出、注销账户。

代码展示

// ATM.javapublic class ATM {private int id;private String name;private char sex;private double moneyLeft;private double moneyCon;private String code;public ATM() {}public ATM(int id, String name, char sex, double moneyLeft, double moneyCon, String code) {this.id = id;this.name = name;this.sex = sex;this.moneyLeft = moneyLeft;this.moneyCon = moneyCon;this.code = code;}public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public char getSex() {return sex;}public void setSex(char sex) {this.sex = sex;}public double getMoneyLeft() {return moneyLeft;}public void setMoneyLeft(double moneyLeft) {this.moneyLeft = moneyLeft;}public double getMoneyCon() {return moneyCon;}public void setMoneyCon(double moneyCon) {this.moneyCon = moneyCon;}public String getCode() {return code;}public void setCode(String code) {this.code = code;}
}

// ATMOperator.javapublic class ATMOperator {ArrayList<ATM> ATMlist = new ArrayList<>();//开户public void register() {ATM user = new ATM();Scanner sc = new Scanner(System.in);System.out.println("请输入你的用户名");String name = sc.next();user.setName(name);while (true) {System.out.println("请输入你的性别，‘男’ 或 ‘女’ ");String tmp = sc.next();char sex = tmp.charAt(0);if (sex != '男' && sex != '女') {System.out.println("请输入‘男’ 或 ‘女’");} else {user.setSex(sex);break;}}while (true) {System.out.println("请输入你的密码");String code = sc.next();System.out.println("请确认你的密码");String confirmCode = sc.next();if (code.equals(confirmCode)) {user.setCode(code);break;} else {System.out.println("两次密码不一致，请重新输入密码");}}System.out.println("请输入你的每次取款限额");double moneyCon = sc.nextDouble();user.setMoneyCon(moneyCon);String id = "";Random r = new Random();for (int i = 0; i < 7; i++) {int num = r.nextInt(10);id += num;}System.out.println("恭喜你，开户成功！卡号是：" + id);int id1 = Integer.parseInt(id);user.setId(id1);ATMlist.add(user);}//查询打印账户信息public void print(int n) {System.out.println("----------" + ATMlist.get(n).getName() + "先生的账户信息----------");System.out.println("账户卡号：" + ATMlist.get(n).getId());System.out.println("账户名：" + ATMlist.get(n).getName());System.out.println("性别：" + ATMlist.get(n).getSex());System.out.println("余额：" + ATMlist.get(n).getMoneyLeft());System.out.println("取款限额：" + ATMlist.get(n).getMoneyCon());System.out.println("--------------------------------");}//展示登录界面public void showLogon(int user) {Scanner sc = new Scanner(System.in);while (true) {System.out.println("请输入你需要办理的业务号");System.out.println("1、查询打印账户信息");System.out.println("2、存款");System.out.println("3、取款");System.out.println("4、转账");System.out.println("5、修改密码");System.out.println("6、退出");System.out.println("7、注销账户");String n = sc.next();switch (n) {case "1":print(user);break;case "2":saveMoney(user);break;case "3":getMoney(user);break;case "4":transforAccounts(user);break;case "5":changePassword(user);break;case "6":return;case "7":unsubscribe(user);break;default:System.out.println("请输入正确的指令");break;}}}//登录账户public int logon() {if (ATMlist.size() == 0) {System.out.println("您还未开户，请先开户");throw new RuntimeException("Exception occurred");}Scanner sc = new Scanner(System.in);System.out.println("请输入你的卡号");int id = sc.nextInt();int tmp = -1;for (int i = 0; i < ATMlist.size(); i++) {if (ATMlist.get(i).getId() == id) {System.out.println(ATMlist.get(i).getName() + "先生，您已经成功登录账户");tmp = i;break;}}if (tmp == -1) {System.out.println("您输入的卡号不存在");throw new RuntimeException("Exception occurred");} else {showLogon(tmp);return tmp;}}//存款public void saveMoney(int user) {Scanner sc = new Scanner(System.in);System.out.println("请输入你要存的金额");double saveMoney = sc.nextDouble();double rs = saveMoney + ATMlist.get(user).getMoneyLeft();System.out.println("存钱成功！您的余额为：" + rs);ATMlist.get(user).setMoneyLeft(rs);}//取款public void getMoney(int user) {Scanner sc = new Scanner(System.in);System.out.println("请输入你要取的金额");double money = sc.nextDouble();if (money > ATMlist.get(user).getMoneyLeft()) {System.out.println("余额不足，取款失败");} else {double rs = ATMlist.get(user).getMoneyLeft() - money;ATMlist.get(user).setMoneyLeft(rs);System.out.println("取款成功！你的余额为：" + ATMlist.get(user).getMoneyLeft());}}//转账public void transforAccounts(int user) {Scanner sc = new Scanner(System.in);System.out.println("请输入你的转账对象的卡号");int id = sc.nextInt();for (int i = 0; i < ATMlist.size(); i++) {if (id == ATMlist.get(i).getId()) {System.out.println("请问是要给*" + ATMlist.get(i).getName().substring(1) + "转账吗？");String tmp = sc.next();char answer = tmp.charAt(0);if (answer == (ATMlist.get(i).getName().charAt(0))) {System.out.println("请输入你要转账的金额");double money = sc.nextDouble();if (money > ATMlist.get(user).getMoneyLeft()) {System.out.println("你的余额不足，转账失败");return;} else {if (money > ATMlist.get(user).getMoneyCon()) {System.out.println("超出取款限额，请重试");return;} else {double rs = ATMlist.get(user).getMoneyLeft() - money;ATMlist.get(user).setMoneyLeft(rs);double otherrs = ATMlist.get(i).getMoneyLeft() + money;ATMlist.get(i).setMoneyLeft(otherrs);System.out.println("转账成功！您的余额为：" + rs);}}} else {System.out.println("你输入的对方账户姓氏不正确，请重试");return;}}else System.out.println("卡号输入有误，请重试");}}//修改密码public void changePassword(int user) {Scanner sc = new Scanner(System.in);System.out.println("确认为本人，请输入你的新密码");String newcode = sc.next();System.out.println("请确认新密码");String confirmCode = sc.next();if (newcode.equals(confirmCode)) {ATMlist.get(user).setCode(newcode);System.out.println("修改密码成功！请牢记密码");} else {System.out.println("两次密码不一致，请重试");return;}}//退出public void exit() {;}//注销账户public void unsubscribe(int user) {Scanner sc = new Scanner(System.in);while (true) {System.out.println("你确定要注销该账户？y/n");String answer = sc.next();if (answer.equals("y")) {System.out.println("你已成功注销账户");ATMlist.remove(user);break;} else if (answer.equals("n")) {System.out.println("你选择了保留账户");break;} else {System.out.println("请输入 y/n");}}}public void start() {Scanner sc = new Scanner(System.in);while (true){System.out.println("请选择你要进行的操作");System.out.println(("1、开户"));System.out.println("2、登录账户");System.out.println("0、退出系统");String num = sc.next();switch (num) {case "0":return;case "1":register();break;case "2":int user = logon();break;default:System.out.println("请输入正确的指令");break;}}}
}

// Test.java (测试用例)public class Test {public static void main(String[] args) {ATMOperator ts = new ATMOperator();ts.start();}
}

场景测试

1、首先是在未开户情况下的登录账户操作：

2、开户

（一）性别乱填

（二）密码输入不一致

（三）正常开户

3、登录账户，但是登录密码错误

4、成功登录账户

a. 查询打印账户信息

b. 存款取款

c.转账（这里转账卡号输错情况写错了，截图懒得改了....)

转账需要2个用户，我先开2个用户，并给梨花存2000元：

现在我用梨花的账户给小王’转账2500：

余额不足，那我转1500：

超出梨花转账限额，那我转100：

 成功！

d.修改密码

e.注销账户

以上就是所有基本功能！

感谢阅读！！