import java.awt.*;
import javax.swing.*;
import java.util.concurrent.*; //*3 Use special thread-safe implementations

/**
 * Main program for Threads demo
 */
public class Main {
    /** Our Row's */
    private CopyOnWriteArrayList<Row> rows = new CopyOnWriteArrayList<Row> (); //*3

    public static void main (String [] args) {
	java.awt.EventQueue.invokeLater (new Runnable() {
            public void run() {
		new Main ();
            }
        });
    }

    public Main () {
	// Window setup
	JFrame frame = new JFrame();
	frame.setSize (500, 500);
	frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);

	// Our canvas
	Canvas canvas = new Canvas (this);
	frame.add (canvas);

	// Show our window
	frame.setVisible (true);

	// Now create our Row's
	for (int i=0; i<5; i++) { //*1 Create our Row's and remember them in ivar
	    Row r = new Row (new Rectangle (10, 100+i*75, 500-40, 40), canvas); //*1
	    rows.add (r); //*1
	}
    }

    public void drawCanvas (Graphics g) {
	// Draw each of our Row's
	for (Row r: rows) r.draw (g); //*2 Draw each of our Row's
    }
}