import java.awt.Graphics;
import javax.swing.JPanel;
import javax.swing.JFrame;

public class RectSpiral extends JPanel
{
    public void paintComponent(Graphics g)
    {
        int width = getSize().width;
        int height = getSize().height;

        int widthCenter = width / 2;
        int heightCenter = height / 2;

        for (int i = 0; i <= 7 ; i++)
        {
           g.drawLine(10*i, 10*(i+1), width - 10*(i+1), 10*(i+1));
           g.drawLine(widthCenter-5-10*i, heightCenter + 5 + 10*i, widthCenter + 5 + 10*i, heightCenter + 5 + 10*i );
           g.drawLine(widthCenter + 5 + 10*i, heightCenter - 4 - 10*(i), widthCenter + 5 + 10*i, heightCenter + 5 + 10*i);
           g.drawLine(10 + 10*i, 20 + 10*(i), 10 + 10*i, height - 10*(i+ 1));
        }
    }

    public static void main(String[] args)
    {
        RectSpiral panel = new RectSpiral();

        JFrame application = new JFrame();

        application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        application.add(panel);
        application.setSize(170, 190);
        application.setVisible(true);
    }
}