高分悬赏解决一个程序有关问题

import java.awt.BorderLayout;
public class Login extends JFrame {

	private JPanel contentPane;
	private JTextField textField;
	private TextField passwordField;
	Connection con;
	java.sql.Statement stmt;
	ResultSet rs;

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					Login frame = new Login();
					frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}

	/**
	 * Create the frame.
	 */
	public Login() {
		setTitle("\u8D44\u4EA7\u6E05\u67E5\u7CFB\u7EDF");
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setBounds(100, 100, 455, 274);
		contentPane = new JPanel();
		contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
		contentPane.setLayout(new BorderLayout(0, 0));
		setContentPane(contentPane);
		
		JPanel panel = new JPanel();
		contentPane.add(panel, BorderLayout.NORTH);
		
		JLabel label = new JLabel("\u6B22\u8FCE\u4F7F\u7528\u5357\u4EAC\u6653\u5E84\u5B66\u9662\u8D44\u4EA7\u6E05\u67E5\u7CFB\u7EDF");
		label.setFont(new Font("微软雅黑", Font.BOLD, 13));
		panel.add(label);
		
		JPanel panel_1 = new JPanel();
		contentPane.add(panel_1, BorderLayout.CENTER);
		
		JLabel label_1 = new JLabel("\u7528\u6237\u540D \uFF1A");
		label_1.setFont(new Font("宋体", Font.BOLD, 12));
		
		JLabel label_2 = new JLabel("\u5BC6  \u7801 \uFF1A");
		label_2.setFont(new Font("宋体", Font.BOLD, 12));
		
		textField = new JTextField();
		textField.setColumns(10);
		
		passwordField = new TextField();
		passwordField.setEchoChar('*');
		GroupLayout gl_panel_1 = new GroupLayout(panel_1);
		gl_panel_1.setHorizontalGroup(
			gl_panel_1.createParallelGroup(Alignment.LEADING)
				.addGroup(gl_panel_1.createSequentialGroup()
					.addGap(94)
					.addGroup(gl_panel_1.createParallelGroup(Alignment.TRAILING)
						.addGroup(gl_panel_1.createSequentialGroup()
							.addComponent(label_2)
							.addGap(18)
							.addComponent(passwordField, 118, 118, 118))
						.addGroup(gl_panel_1.createSequentialGroup()
							.addComponent(label_1)