import java.awt.*;

class SetOfLights extends Thread {
    
    private Canvas area;
    private int    x;
    boolean walk = false;
    private static final int red = 0;
    boolean walkOn = false;
    
    SetOfLights(Canvas c, int x) {
        area = c;
        this.x = x;
    }
    
    public void run() {
        while(true) {
            for(int light=0; light<3; light++) {
                if(light == red & walk ) {
                    walkOn = false;
                    for( int i=0; i<11; i++ ){
                        draw(light);
                        try {
                            sleep(500);
                        } catch(InterruptedException e) {}
                        walkOn = !walkOn ;
                    }
                    walk = false;            
                } else {
                    draw(light);
                    try{
                        sleep(500);
                    } catch (InterruptedException e) {}
                } // end if-else
           } // end for     
        } // end while
    }
    
    public void draw(int light) {
        Graphics g = area.getGraphics();
        
        g.setColor(Color.black);
        g.drawOval(x-8,10,30,68);
        g.drawOval(x,85,15,15);
               
        g.drawString("RED", x-90, 28);
        g.drawString("YELLOW", x-90,48);
        g.drawString("GREEN", x-90, 68);
        g.drawString("WALK", x-90,98);
        
        switch(light) {
        case 0:
            g.setColor(Color.red);
            g.fillOval(x,15,15,15);
            g.setColor(Color.lightGray);
            g.fillOval(x,35,15,15);
            g.fillOval(x,55,15,15);
            break;

        case 1:            
            g.setColor(Color.green);
            g.fillOval(x,55,15,15);
            g.setColor(Color.lightGray);
            g.fillOval(x,15,15,15);
            g.fillOval(x,35,15,15);
            break;
        
        case 2:
            g.setColor(Color.yellow);
            g.fillOval(x,35,15,15);
            g.setColor(Color.lightGray);
            g.fillOval(x,15,15,15);
            g.fillOval(x,55,15,15);
            break;
        }
    }
}