import java.awt.*;				// used for Graphics
import javax.swing.*;			// used for JFrame, JPanel

public class RecursiveDrawer
{
	public static void main(String[] args)
	{
		JFrame frame=new JFrame("");
		frame.setSize(600,600);
		DrawPanel p=new DrawPanel();
		frame.add(p);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.setVisible(true);
	}
	
	public static class DrawPanel extends JPanel
	{
		public void paintComponent(Graphics g)
		{
			draw(g, 300,300,150,0);				// start recursive call using 300,300 as starting point for the 3 lines, each line size is 150
		}
		
		public void draw(Graphics g, int x, int y, int size, int c)		// c is a counter, once it is too big, we won't have enough resolution to continue to recurse
		{
			if(c<8) 							// recurse only 7 times
			{
				g.drawLine(x-size/2,y,x,y);		// draw 3 lines, left of x,y, right of x,y, up from x,y
				g.drawLine(x,y,x+size/2,y);
				g.drawLine(x,y-size/2,x,y);
				draw(g,x-size/2,y,size/2,c+1);	// recurse with three new midpoints, one to the left of x,y, one to the right of x,y, one above x,y
				draw(g,x+size/2,y,size/2,c+1);
				draw(g,x,y-size/2,size/2,c+1);								
			}

		}
	}
}