///////////NightSky.java////////////
import java.awt.*;
import java.applet.Applet;
import java.util.Random;
 
public class NightSky extends Applet 
{
    public static void main(String[] args) 
    {
        Applet applet = null;
 
        if( args.length > 0 )
            try
            {
                applet = new NightSky( Integer.parseInt(args[0]) );
            }
            catch( NumberFormatException nfe )
            {
                System.out.println( args[0] + 
                    " doesn't grok as a number, proceeding " + 
                    "with defaults..." );
            }
 
        if( applet == null )
            applet = new NightSky();
 
        javax.swing.JFrame frame = new javax.swing.JFrame("Night Sky");
 
        // To close the application:
        frame.setDefaultCloseOperation( javax.swing.JFrame.EXIT_ON_CLOSE );
        frame.getContentPane().add(applet);
        frame.setSize(350,350);
        applet.init();
        applet.start();
        frame.setVisible(true);
    }
 
    private int starCount = 50;
    private Star [] stars;
    private static final Random random = new Random();
    private static Color[] colors = { Color.red,  Color.yellow, Color.green,
                                      Color.cyan, Color.magenta, Color.blue };    
 
    public NightSky()
    {
    }
 
    public NightSky( int starCount )
    {
        this.starCount = starCount;
    }
 
    public void init ()
    {
        stars = new Star[starCount];
 
        for( int i = 0; i < stars.length; i++ )
            stars[i] = new Star( random.nextInt(300), 
                                 random.nextInt(300), 
                                 10 + random.nextInt(5), // Slight variation in size.
                                 4 + random.nextInt(3),
                                 colors[random.nextInt(colors.length)] );
 
        setBackground (Color.black);
    }
    
    
    public void paint(Graphics page) 
    {
        for( int i = 0; i < stars.length; i++ )
            stars[i].draw(page);
    }
}
 
class Star 
{
 
    private int centerX;
    private int centerY;
    private int radius ;
    private Color color;
    private int totalLines ;
    
    public Star (int centerX, int centerY, int radius, int totalLines, Color shade) 
    {
        this.centerX = centerX ;
        this.centerY = centerY ;
        this.radius = radius ;
        this.totalLines = totalLines ;
        color = shade;
    }
    
    public Star (int centerX, int centerY, int radius, Color shade) 
    {
        // Default the total lines to 6
        this(centerX, centerY, radius, 6, shade) ;
    }
    
    public Star (int center, int radius, Color shade) 
    {
        // centerX and centerY are same
        this(center, center, radius, 6, shade) ;
    }
    
    public void draw (Graphics page)
    {
    
        double angle = 2*Math.PI/totalLines;
        
        for (int i = 0; i < totalLines; i++)
        {
            int x1 = (int) (radius * Math.cos ( angle * i));
            int y1 = (int) (radius * Math.sin ( angle * i));
            
            x1 = centerX + x1;
            y1 = centerY + y1;
            page.setColor ( color ) ;
            page.drawLine ( centerX, centerY, x1, y1);
        }
    }
}