如何将新对象参数存储为HashMap的值？代码问题求助

我尝试将注册窗口输入的用户名、密码等用户信息存储到HashMap中，计划用username作为键，对应值为完整的Client对象，但目前无法正确保存输入的参数。以下是现有代码：

Client.class #

public  class Client {
    
    public String name;
    public String username;
    public String password;
    public Double balance;
    public String address;
    public String phone;
    private ArrayList<Account> accounts;
    
    // Default Constructor
    public Client() {
        name = "";
        address = "";
        phone = "";
        username = "";
        password = "";
        balance = 0.0;
        
    }

    // Parameterized Constructor
    public Client(String name, String username,String password, String phone, String address, Date date) {
        
        this.name = name;
        this.username = username;
        this.password = password;
        this.address = address;
        this.phone = phone;
        accounts = new ArrayList<>();
    }
    
    public ArrayList<Account> getStringList(String acc_num, String From, String To) {
        return accounts;
    }
    
    public void setStringList(ArrayList<Account> accounts) {
        this.accounts = accounts;
    }
    
    
    void showClientInfo() {
        System.out.println("Name: "+name);
        System.out.println("Phone Name: "+phone);
        System.out.println("Address Name: "+address);
    }
    
    
    public Account getAccount(String acctNum) {
        for(Account a: accounts) {
            if(acctNum.equals(a.getAccountNumber())) {
                return a;
            }
        }
        return null;
    }
    
    public boolean removeAccount(String acctNum) {
        Account a = getAccount(acctNum);
        if(a != null) {
            a.setActive(false);
            accounts.remove(a);
            return true;
        }
        return false;
    }
    
    public String getName() {
        return name;
    }
    
    public void setName(String name) {
        if (name != null && !name.isEmpty()) {
            this.name = name;
        }
    }
    
    public String getPhone() {
        return phone;
    }
    
    public void setPhone(String phone) {
        if (phone != null && !phone.isEmpty()) {
            this.phone = phone;
        }
    }
    
    
    public String getAddress() {
        return address;
    }
    
    public void setAddress(String address) {
        this.address = address;
    }
    
    public String getUsername() {
        return username;
    }
    
    public void setUsername(String username) {
        this.username = username;
    }
    
    public String getPassword() {
        return password;
    }
    
    public void setPassword(String password) {
        this.password = password;
    }

    
    // end of class
}

Bank_Account.class #

// Bank_Account Class
public class Bank_Account {
    
 
    public Client newClient = new Client();
    public String username,password;
    public static HashMap<String, Client> clientMap;
    
    // constructor
    public Bank_Account(String username, String password) {
        this.username = username;
        this.password = password;
        clientMap = new HashMap<String, Client>();
    }
    
    // updates the object member variables
    public void addInfo(String username, String password, String name, String address, String phone) {
        
        newClient = new Client(username, password, name, address, phone, new Date());
        if (newClient != null) {
            clientMap.put(newClient.getUsername(), newClient);
        }
    }
    
    public boolean closeAccount(String username, String acctNum) {

        Client client = clientMap.get(username);
        if (client != null) {
            return client.removeAccount(acctNum);
        }
        
        return false;
        
    }
    
    
    public static void displayCustomerInformation(Client client){
        if(client != null){
            System.out.println(client);
        }
    }
    
    public static  Map<String, Client> getLoginInfo() {
        return clientMap;
    }
    
    public int addAmount(int b) {
        return 0;
        }
        
    public static String getDate() {
        return getDate();
    }
    
    public int removeAmount(int b) {
        return 0;
    }
    
    public void updateBalance() {
        
    }
    
    
    public void finalize() {
        System.out.println("Bank Account Destructor");
    }

    
    // end of class
}

Sign up GUI.class #

//function executed when Verify Account Button is clicked
        btn_Create_Account.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
        
                
                //set username/password text field as parameter for bank account constructor
                Bank_Account bank = new Bank_Account(tf_UserName.getText(), tf_Pass.getText());
            
                //save username/password text field
                String userId = tf_UserName.getText();
                String password = tf_Pass.getText();
                    
                // check if user exists 
                if (Bank_Account.clientMap.containsKey(userId)) {
                        
                    System.out.println("usernmae already exists " + userId );
                    JOptionPane.showMessageDialog(f,"username already exists ");
                
                    }
                
                //check if password created contains specials characters
                else if(!password.matches((((?=.*\\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[!@#$%^&*_]).{8,})))) {
                        
                        JOptionPane.showMessageDialog(f, "Invalid password condition. Set again :");
                        
                        }
                
                //if user does not exist put inside hashmap and insert password inside client class
                else {
                        System.out.println(Bank_Account.clientMap);
                        Bank_Account.clientMap.put(userId, client);
                        JOptionPane.showMessageDialog(f, "Account registered successfully " );
                        // **************************************
                        System.out.println("account registered "+ Bank_Account.clientMap.get(userId) + Bank_Account.getLoginInfo());
                        frame.remove(f);
                        frame.repaint();
                        frame.validate();
                        openSignInForm(frame, client);
                    }
                    
                
            }
                    
                    
        });
    }

核心问题点 #

1. 静态clientMap被重复初始化
   每次点击按钮创建Bank_Account实例时，构造方法都会重新创建一个新的HashMap，导致之前存储的用户信息全部丢失。
2. GUI代码未初始化Client对象
   注册逻辑中直接使用未初始化的client变量存入Map，导致存入的是无效对象。
3. getDate()方法无限递归
   return getDate();会触发无限递归，最终导致栈溢出。

修复步骤 #

1. 修正Bank_Account类的静态Map初始化

将静态Map的初始化移到静态代码块，确保只执行一次：

public class Bank_Account {
    public Client newClient = new Client();
    public String username,password;
    public static HashMap<String, Client> clientMap;
    
    // 静态初始化块，仅在类加载时执行一次
    static {
        clientMap = new HashMap<String, Client>();
    }
    
    // 构造方法移除Map初始化逻辑
    public Bank_Account(String username, String password) {
        this.username = username;
        this.password = password;
    }
    
    // 修复getDate()方法，返回当前时间字符串
    public static String getDate() {
        return new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date());
    }
    
    // 其他方法保持不变...
}

2. 修正GUI注册逻辑

先收集所有用户输入，创建完整的Client对象后再存入Map：

btn_Create_Account.addActionListener(new ActionListener() {
    public void actionPerformed(ActionEvent e) {
        String userId = tf_UserName.getText();
        String password = tf_Pass.getText();
        // 假设存在对应输入框获取姓名、地址、电话
        String name = tf_Name.getText();
        String address = tf_Address.getText();
        String phone = tf_Phone.getText();
        
        // 先检查用户是否存在，避免重复创建实例
        if (Bank_Account.clientMap.containsKey(userId)) {
            System.out.println("username already exists " + userId );
            JOptionPane.showMessageDialog(f,"username already exists ");
        } else if(!password.matches("(?=.*\\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[!@#$%^&*_]).{8,}")) {
            JOptionPane.showMessageDialog(f, "Invalid password condition. Set again :");
        } else {
            // 创建完整的Client对象
            Client newClient = new Client(name, userId, password, phone, address, new Date());
            Bank_Account.clientMap.put(userId, newClient);
            JOptionPane.showMessageDialog(f, "Account registered successfully " );
            System.out.println("account registered "+ Bank_Account.clientMap.get(userId));
            frame.remove(f);
            frame.repaint();
            frame.validate();
            openSignInForm(frame, newClient);
        }
    }
});

3. 可选：为Client类添加toString()方法

方便打印查看用户信息：

@Override
public String toString() {
    return "Client{" +
            "name='" + name + '\'' +
            ", username='" + username + '\'' +
            ", address='" + address + '\'' +
            ", phone='" + phone + '\'' +
            '}';
}

内容的提问来源于stack exchange，提问作者sillyconAdmin