package DoubleDeckerBus; import javax.swing.*; import java.awt.*; import DoubleDeckerBus.DrawningObjects.*; public class Canvas extends JComponent { public DrawningBus DrawningBus; public void paintComponent (Graphics g){ if (DrawningBus == null){ return; } super.paintComponents (g) ; Graphics2D g2d = (Graphics2D)g; DrawningBus.DrawTransport(g2d); super.repaint(); } }