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

public class Draw
{
	public static void main(String args[])
	{
		JFrame frame = new JFrame("Draw");
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

		DrawPanel panel = new DrawPanel();

		frame.add(panel);
		frame.setPreferredSize(new Dimension(1000, 500));

		frame.pack();
		frame.setVisible(true);
	}
}

class DrawPanel extends JPanel
{
	public void paintComponent(Graphics g)
	{
		super.paintComponent(g);

		g.drawLine(0, 0, getWidth(), getHeight());
		g.drawRect(20, 20, getWidth()-100, getHeight()-100);
	}
}