The example draws several moving wadges on a circle

/* The example draws several moving wadges on a circle. These wedges move with different speeds */
import java.applet.*;
import java.awt.*;
import java.util.*;

public class DrawMultWedges extends Applet {
Wedges t [] = new Wedges [6];
Graphics g;

public void init ()
{
g = getGraphics ();

for (int i = 0; i < t.length; i++)
{
if ( i < t.length / 2)
t [i] = new Wedges (g, 10, 10 + i * 100, 100, 100, 100 * (i + 1));
else
t [i] = new Wedges (g, 110, 10 + (i - 3) * 100, 100, 100, 100 * (i + 1));
t [i].start ();
}
}

public void paint (Graphics g)
{
}
}

class Wedges implements Runnable {
int x, y, width, height, interval;
Graphics g;
volatile boolean isSet = true;
Thread t;

public Wedges (Graphics g, int x, int y, int width, int height, int interval)
{
this.g = g;
this.x = x;
this.y = y;
this.width = width;
this.height = height;
this.interval = interval;

t = new Thread (this);
}

public void start ()
{
t.start ();
}

public void run ()
{
int i = 0;

if (g == null)
{
System.out.println ("The reference to Graphics is " + g);
return;
}
g.drawArc (x, y, width, height, 0, 360); // draw a circle
while (isSet)
{
g.setColor (Color.white);
g.fillArc (x, y, width, height, i - 45, 45); // erase a wedge
g.setColor (Color.black);
g.drawArc (x, y, width, height, i - 45, 45); // draw a circle sector
g.fillArc (x, y, width, height, i, 45); // draw a wedge
if (i != 315)
i += 45;
else
i = 0;
System.out.println (i);
try
{
Thread.sleep (interval);
} catch (InterruptedException ie)
{
System.out.println (ie.getMessage ());
}
}
g.dispose ();
}

}