银行系统（Java）异常处理

package analog_ATM;
import java.io.IOException;
//import java.sql.*;
import java.util.*;

/**
 * 1.账户类,模拟ATM机，即读取了用户的个人信息
 * 2.查询余额
 * 3.交易记录
 * 4.存/取
 * 5.其他功能
 */

class InsufficientFundsException extends Exception{//自定义异常类
	Account account;   //貌似有危险
	private double dAmount;
	InsufficientFundsException(){}  //无参
	InsufficientFundsException(Account account, double dAmount){
		this.account = account;
		this.dAmount = dAmount;
	}
	
	public String getMessage(){  //错误信息
		String str = "取款失败！账户余额：" + account.getBalance()+ "，取款额：" + dAmount + "，余额不足";
		return str;
	}
}

class Account{
	boolean isUseful = true;    //卡是否可用
	String cardNumber;   //4位数的卡号，由银行按照规定分配
	String userName;  //用户名
	String password;  //密码
	double balance;  //余额
	
	Account(){
		this.isUseful = true;
		this.balance = 0.0;
	}
	Account(String cardNumber, String userName, String password){
		this.isUseful = true;
		this.balance = 0.0;
		this.cardNumber = cardNumber;
		this.userName = userName;
		this.password = password;
	}
	//
	//public void setCardNumber() {
		//Random rnd = new Random();
		 //rnd.setSeed(9999);
	//}
	//
	public void setUserName() throws IOException{//cin exception
		Scanner sc = new Scanner(System.in);
		System.out.println("请输入您的用户名：");
		this.userName = sc.nextLine();
	}
	//
	public void setPassword() throws IOException {//cin exception
		Scanner sc = new Scanner(System.in);
		System.out.println("请输入您的密码：");
		this.password = sc.nextLine();
	}
	//查余额
	public double getBalance(){
		return this.balance;
	}
	//取
	public void withdraw(double money) throws InsufficientFundsException{
		if (balance < money) {
			throw new InsufficientFundsException(this, money);
		}
		balance = balance - money;
		System.out.println("取款成功！账户余额为" + balance);
	}
	//查记录
	public void recordsInfo() {
		
	}	
    //存
	public void saveMoney(double money) {
		this.balance += money;
		System.out.println("存款成功！新余额为："+this.balance);
	}
}
//银行系统
class Bank{
	
	Account card[];
	static int current_account_index = 0;
	static int accountNumber = 0;  //账户数量
	static int illegalCardNumber = 0;   //冻结数量
	
	Bank(){
		card = new Account[1];
		card[0] = new Account("1000", "root", "password");
		accountNumber ++;
	}
	
	void addAccount() throws IOException, InsufficientFundsException {
		Account [] temp = card;
		card = new Account[accountNumber + 1];
		for(int i = 0; i<accountNumber; i++) {
			card[i] = new Account();
			card[i] = temp[i];
		}
		card[accountNumber] = new Account();
		card[accountNumber].cardNumber = String.valueOf(accountNumber + 1000);
		card[accountNumber].setUserName();
		card[accountNumber].setPassword();
		System.out.println("注册成功，卡好为："+card[accountNumber].cardNumber);
		accountNumber++;
		load();
	}
	
	void cutAccount(String cardNumber) {
		//系统发现恶意账户，应该立刻冻结它.
		//卡丢了，立刻冻结
		//根据卡号冻结
		for (Account ac: card) {
			if(ac.cardNumber.equals(cardNumber)) {
				ac.isUseful = false;
				illegalCardNumber++;
			}
		}
	}
	//
	void load() throws IOException, InsufficientFundsException{
		System.out.println("*********************欢迎进入xx银行登录界面***********************");
		System.out.println("1:登录\t2.注册\t3.退出");
		Scanner sc = new Scanner(System.in);
		System.out.println("请选择功能：");
		int i = sc.nextInt();
		if (i==1) {
			loadInfo();
			}
		if (i==2) {
			addAccount();
			}
		if (i==3) {
			System.exit(0);
			}
	}
	
	//
	void mainWnd() throws IOException, InsufficientFundsException{
		System.out.println("欢迎进入银行系统!");
		System.out.println("*****************银行系统************************");
		while (true){
			System.out.println("1:存钱    \t2.取钱    \t3.查看余额\t4.挂失    \t5.退出    ");
			Scanner sc = new Scanner(System.in);
			System.out.println("请选择功能：");
			int i = sc.nextInt();
			if(i==5) {break;}
			if(i==1) {
				if(card[current_account_index].isUseful == true) {
					System.out.println("请输入存款金额：");
					double money = sc.nextDouble();
					card[current_account_index].saveMoney(money);}
				else {System.out.println("账户以被冻结");break;}
			}
			if(i==2) {
				if(card[current_account_index].isUseful == true) {
					System.out.println("请输入取款金额：");
					double money = sc.nextDouble();
					card[current_account_index].withdraw(money);
					}
				else {System.out.println("账户以被冻结");break;}
				}
			if(i==3) {
				if(card[current_account_index].isUseful == true) {
					System.out.println("余额为："+card[current_account_index].getBalance());}
				else {System.out.println("账户以被冻结");break;}
			}
			if(i==4) {if(card[current_account_index].isUseful == true) {
					cutAccount(card[current_account_index].cardNumber);}
			else {System.out.println("账户以被冻结");break;}
			}
		}
		System.exit(0);
	}
	
	void loadInfo() throws IOException, InsufficientFundsException{
		Scanner sc = new Scanner(System.in);
		System.out.println("请输入卡号：");
		String cardNumber = sc.nextLine();
		System.out.println("请输入密码：");
		String password = sc.nextLine();
		for (Account ac: card) {
			if(ac.isUseful == true && ac.cardNumber.equals(cardNumber) && ac.password.equals(password)) {
				System.out.println("登录成功！");
				mainWnd();
			}
			current_account_index++;
		}
		System.out.println("卡号或者密码错误！请重新登录");
		loadInfo();
	}
}


//test
public class ATM {

	public static void main(String[] args) throws IOException{
		// TODO Auto-generated method stub
		Bank b = new Bank();
		//System.out.println(b.card[0].balance);
		
		try {
			b.load();
		} catch (InsufficientFundsException e) {
			// TODO Auto-generated catch block
			System.out.println(e.getMessage());
		}
	}
}