import java.awt.Graphics;
import javax.swing.JPanel;

/**
 * For drawing stuffs using an ILambda command!
 */
public class GraphCanvas extends JPanel {
    private ILambda _drawing = NoOpLambda.Singleton; // Null Object Pattern!

    public void setDrawable(ILambda drawing) {
        _drawing = drawing;
    }

    public void paintComponent (Graphics g) {
        super.paintComponent (g);
        _drawing.apply (g);
    }
}