登陆界面核心代码java

以下是一个基本的登陆界面的Java代码：

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class Login extends JFrame implements ActionListener {
    private JPanel panel;
    private JTextField usernameField;
    private JPasswordField passwordField;
    private JLabel usernameLabel, passwordLabel, messageLabel;
    private JButton loginButton;

    public Login() {
        setTitle("Login");
        setSize(350, 200);
        setDefaultCloseOperation(EXIT_ON_CLOSE);

        panel = new JPanel();
        panel.setLayout(null);

        usernameLabel = new JLabel("Username:");
        usernameLabel.setBounds(10, 20, 80, 25);
        panel.add(usernameLabel);

        usernameField = new JTextField(20);
        usernameField.setBounds(100, 20, 165, 25);
        panel.add(usernameField);

        passwordLabel = new JLabel("Password:");
        passwordLabel.setBounds(10, 50, 80, 25);
        panel.add(passwordLabel);

        passwordField = new JPasswordField(20);
        passwordField.setBounds(100, 50, 165, 25);
        panel.add(passwordField);

        loginButton = new JButton("Login");
        loginButton.setBounds(10, 100, 80, 25);
        loginButton.addActionListener(this);
        panel.add(loginButton);

        messageLabel = new JLabel("");
        messageLabel.setBounds(10, 130, 300, 25);
        panel.add(messageLabel);

        add(panel);
        setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == loginButton) {
            String username = usernameField.getText();
            String password = passwordField.getText();

            if (username.equals("admin") && password.equals("password")) {
                messageLabel.setText("Login successful!");
            } else {
                messageLabel.setText("Invalid username or password!");
            }
        }
    }

    public static void main(String[] args) {
        new Login();
    }
}

这个代码创建了一个基本的登陆界面，包括一个用户名输入框、一个密码输入框、一个登陆按钮和一个信息提示标签。当用户点击登陆按钮时，程序会检查用户名和密码是否正确，并在信息提示标签上显示相应的信息。