求助！这个问题是什么意思呢

有方法没有定义返回值，17行截出来看看，代码多处错误：

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

public class Login extends JFrame {
	/** * */
	private static final long serialVersionUID = 1L;
	JLabel a1 = new JLabel("账号：");
	JLabel a2 = new JLabel("密码：");
	JButton b1 = new JButton("确定");
	JButton b2 = new JButton("重置");
	JTextField jt;
	JPasswordField jp;
	public Login() {
		setTitle("登录");
		setBounds(500, 250, 300, 200);
		setVisible(true);
		setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
		Container cp = getContentPane();
		 jt = new JTextField(15);
		 jp = new JPasswordField(15);
		JPanel p1 = new JPanel();
		p1.add(a1);
		p1.add(jt);
		
		JPanel p2 = new JPanel();
		p2.add(a2);
		p2.add(jp);
		
		JPanel p3 = new JPanel();
		p3.add(b1);
		p3.add(b2);
		
		cp.add( p1,BorderLayout.NORTH);
		cp.add(p2,BorderLayout.CENTER);
		cp.add( p3,BorderLayout.SOUTH);
		
		b2.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arge0) {
				jt.setText("");
				jp.setText("");
			}
		});
		b1.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String t1 = jt.getText();
				String jt1 = "test1";
				if ((t1.trim().equals(jt1))
						&& new String(jp.getPassword()).trim().equals("test1")) {
					JOptionPane.showMessageDialog(null, "登录成功");
				} else {
					JOptionPane.showMessageDialog(null, "用户或密码错误，请重新输入");
				}
			}
		});
	}
	
	public static void main(String[] args) {
		new Login();
	}
}

函数申明没有写返回值类型

打开sgb.java文件，看看17行代码有什么问题。