bha

public class FertilizerGraph extends JComponent implements Observer {		public void paintComponent(Graphics g){				Graphics2D g2 = (Graphics2D) g;		Rectangle box = new Rectangle(5,10,10,30);		g2.draw(box);	}		public void update(Observable o, Object a){			}}//in my gui class constructor		FertilizerGraph fertgraph = new FertilizerGraph();		f.getContentPane().add(fertgraph, BorderLayout.CENTER);