如何使用netbeans在java上验证从jlabel到jtextfield的值

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

public class MainFrame extends JFrame {
    private JLabel label;
    private JTextField textField;

    public MainFrame() {
        label = new JLabel("请输入姓名：");
        textField = new JTextField(20);

        textField.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                String input = textField.getText();
                if (input.isEmpty()) {
                    JOptionPane.showMessageDialog(MainFrame.this, "请输入姓名");
                } else {
                    JOptionPane.showMessageDialog(MainFrame.this, "您输入的姓名是：" + input);
                }
            }
        });

        add(label);
        add(textField);

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
        setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                new MainFrame();
            }
        });
    }
}