java practice questions - bank customers

package main;
import java.util.ArrayList;
/**
 * (10 points)
 * Do a simple bank and account demonstration program.
 * (1) Define an account class, including attributes such as username, password, balance, and methods such as depositing and withdrawing money.
 * (2) Define a bank class, including attributes such as bank name, account list, etc., and the functions of opening accounts and checking accounts. A list of accounts can use collection-related classes,
 * Such as ArrayList, it is best to use generics at the same time.
 * (3) Define a test class and main function, create a bank in it, open some accounts, simulate depositing money, withdrawing money, displaying balance, etc.
 */
public class Main {
    public static void main(String[] args){
        Bank bank = new Bank("HDBank");
        bank.openAccount("xiaoming","666",0);
        bank.openAccount("xiaoli","777",0);
        bank.openAccount("xiaohong","888",0);
        bank.saveMoney("xiaoli",100);
        // Deposit money to a specific account
        bank.drawMoney("xiaoli",50,"777");
        //To withdraw money from a specific account, you need to verify the password
        bank.showAccount("xiaoli");
        //Display xiaoli account information
        bank.drawMoney("xiaoli",100,"a wrong password");
        //If the password is wrong, the withdrawal of money fails
        bank.drawMoney("xiaoli",100,"777");
        //Insufficient balance
    }
}

class Account{
    private String userName;
    private String password;
    private double balance;
    Account(String userName,String password,double balance){
        this.userName = userName;
        this.password = password;
        this.balance = balance;
    }
    public void save(double money){
        //save money
        balance += money;
        System.out.printf("%s has deposited %.2f yuan, and the account balance is %.2f yuan.\n",userName,money,balance);
    }
    public void draw(double money){
        //Withdraw money, if the account balance is insufficient, the money cannot be withdrawn
        if(balance - money <= 0) {
            System.out.printf("%s withdraws money %.2f, and the account balance is %.2f yuan.",userName,money,balance);
            System.out.println("Insufficient balance, failed to withdraw money.");
        }else {
            balance -= money;
            System.out.printf("%s took %.2f yuan, and the account balance is %.2f yuan.\n", userName, money, balance);
        }
    }
    public void show(){
        //display account information
        System.out.printf("userName:%s\n",userName);
        System.out.printf("balance:%.2f\n",balance);
    }
    public String getUserName(){
        //get username
        return userName;
    }
    public String getPassword(){
        // get the password
        return password;
    }
    public String getInfo(){
        //return account information
        return "userName:"+userName+",banlance:"+balance;
    }
}

class Bank{
    public String bankName;
    private ArrayList<Account> accounts;
    Bank(String bankName){
        this.bankName=bankName;
        accounts=new ArrayList<Account>();
    }
    Bank(String bankName,ArrayList<Account> accounts){
        this.bankName=bankName;
        this.accounts=accounts;
    }
    public void openAccount(String userName,String password,double balance){
        //open an account
        accounts.add(new Account(userName,password,balance));
    }
    public Account seekAccount(String userName){
        //Find the account by user name, if found, return the account, otherwise, return null
        for(Account account:accounts){
            if(userName.equals(account.getUserName()))
                return account;
        }
        return null;
    }
    public void showAccount(String userName){
        Account account=seekAccount(userName);
        if(account==null)
            System.out.println("The account does not exist.");
        else
            account.show();
    }
    public void saveMoney(String userName,double money){
        // Deposit money to a specific account
        Account account = seekAccount(userName); //查找
        if(account==null)
            System.out.println("The account does not exist.");
        else
            account.save(money);
    }
    public void drawMoney(String userName,double money,String password){
        //To withdraw money from a specific account, you need to verify the password
        Account account = seekAccount(userName); //查找
        if(account==null)
            System.out.println("The account does not exist.");
        else {
            if(password.equals(account.getPassword())) {
                account.draw(money);
            }else {
                System.out.println("The password is incorrect. Failed to withdraw money.");
            }
        }
    }
}