private void doDrawing(Graphics g) {

			Graphics2D g2d = (Graphics2D) g;

			g2d.setColor(Color.blue);

			for (int i = 0; i <= 1000; i++) {

				Dimension size = getSize();
				Insets insets = getInsets();

				int w = size.width - insets.left - insets.right;
				int h = size.height - insets.top - insets.bottom;

				Random r = new Random();
				int x = Math.abs(r.nextInt()) % w;
				int y = Math.abs(r.nextInt()) % h;
				g2d.drawLine(x, y, x, y);
			}
		}