java银行系统包括开户，存款，取款，转账，查询，修改密码，销户代码

以下是一个简单的 Java 银行系统的代码实现，包括开户，存款，取款，转账，查询，修改密码，销户功能。

import java.util.ArrayList;
import java.util.Scanner;

public class BankSystem {
    static Scanner scanner = new Scanner(System.in);
    static ArrayList<Account> accounts = new ArrayList<>();

    public static void main(String[] args) {
        while (true) {
            System.out.println("请选择操作：");
            System.out.println("1. 开户");
            System.out.println("2. 存款");
            System.out.println("3. 取款");
            System.out.println("4. 转账");
            System.out.println("5. 查询");
            System.out.println("6. 修改密码");
            System.out.println("7. 销户");
            System.out.println("8. 退出");
            int choice = scanner.nextInt();

            switch (choice) {
                case 1:
                    newAccount();
                    break;
                case 2:
                    deposit();
                    break;
                case 3:
                    withdraw();
                    break;
                case 4:
                    transfer();
                    break;
                case 5:
                    query();
                    break;
                case 6:
                    changePassword();
                    break;
                case 7:
                    deleteAccount();
                    break;
                case 8:
                    return;
                default:
                    System.out.println("输入错误，请重新输入");
                    break;
            }
        }
    }

    // 开户
    static void newAccount() {
        System.out.println("请输入账号：");
        String account = scanner.next();
        System.out.println("请输入密码：");
        String password = scanner.next();
        System.out.println("请输入初始存款金额：");
        double balance = scanner.nextDouble();
        accounts.add(new Account(account, password, balance));
        System.out.println("开户成功");
    }

    // 存款
    static void deposit() {
        System.out.println("请输入账号：");
        String account = scanner.next();
        System.out.println("请输入密码：");
        String password = scanner.next();
        Account acc = getAccount(account, password);
        if (acc != null) {
            System.out.println("请输入存款金额：");
            double amount = scanner.nextDouble();
            acc.deposit(amount);
            System.out.println("存款成功");
        }
    }

    // 取款
    static void withdraw() {
        System.out.println("请输入账号：");
        String account = scanner.next();
        System.out.println("请输入密码：");
        String password = scanner.next();
        Account acc = getAccount(account, password);
        if (acc != null) {
            System.out.println("请输入取款金额：");
            double amount = scanner.nextDouble();
            if (acc.withdraw(amount)) {
                System.out.println("取款成功");
            } else {
                System.out.println("余额不足，取款失败");
            }
        }
    }

    // 转账
    static void transfer() {
        System.out.println("请输入源账号：");
        String account1 = scanner.next();
        System.out.println("请输入密码：");
        String password1 = scanner.next();
        Account acc1 = getAccount(account1, password1);
        if (acc1 == null) {
            return;
        }
        System.out.println("请输入目标账号：");
        String account2 = scanner.next();
        Account acc2 = getAccount(account2);
        if (acc2 == null) {
            return;
        }
        System.out.println("请输入转账金额：");
        double amount = scanner.nextDouble();
        if (acc1.withdraw(amount)) {
            acc2.deposit(amount);
            System.out.println("转账成功");
        } else {
            System.out.println("余额不足，转账失败");
        }
    }

    // 查询
    static void query() {
        System.out.println("请输入账号：");
        String account = scanner.next();
        System.out.println("请输入密码：");
        String password = scanner.next();
        Account acc = getAccount(account, password);
        if (acc != null) {
            System.out.println("余额：" + acc.getBalance());
        }
    }

    // 修改密码
    static void changePassword() {
        System.out.println("请输入账号：");
        String account = scanner.next();
        System.out.println("请输入旧密码：");
        String oldPassword = scanner.next();
        Account acc = getAccount(account, oldPassword);
        if (acc != null) {
            System.out.println("请输入新密码：");
            String newPassword = scanner.next();
            acc.setPassword(newPassword);
            System.out.println("修改密码成功");
        }
    }

    // 销户
    static void deleteAccount() {
        System.out.println("请输入账号：");
        String account = scanner.next();
        System.out.println("请输入密码：");
        String password = scanner.next();
        Account acc = getAccount(account, password);
        if (acc != null) {
            accounts.remove(acc);
            System.out.println("销户成功");
        }
    }

    // 根据账号和密码查找账户
    static Account getAccount(String account, String password) {
        for (Account acc : accounts) {
            if (acc.getAccount().equals(account) && acc.getPassword().equals(password)) {
                return acc;
            }
        }
        System.out.println("账号或密码错误");
        return null;
    }

    // 根据账号查找账户
    static Account getAccount(String account) {
        for (Account acc : accounts) {
            if (acc.getAccount().equals(account)) {
                return acc;
            }
        }
        System.out.println("账号不存在");
        return null;
    }
}

// 账户类
class Account {
    private String account;
    private String password;
    private double balance;

    public Account(String account, String password, double balance) {
        this.account = account;
        this.password = password;
        this.balance = balance;
    }

    public String getAccount() {
        return account;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public double getBalance() {
        return balance;
    }

    public void deposit(double amount) {
        balance += amount;
    }

    public boolean withdraw(double amount) {
        if (balance >= amount) {
            balance -= amount;
            return true;
        } else {
            return false;
        }
    }
}