Spiral motion code in java

import java.applet.*;

import java.awt.*;

public class Sprial extends Applet{

public void paint(Graphics g){

int x=0,y=10,xrate=240,yrate=210;

setBackground(Color.green);

g.setColor(Color.black);

for(int i=1;i<=15;i++){

int m=x;

int n=y;

if(i%4==1){

x+=xrate;

xrate-=30;

}

else if(i%4==2){

y+=yrate;

yrate-=30;

}

else if(i%4==3){

x-=xrate;

xrate-=30;

}

else

{

y-=yrate;

yrate-=30;

}

g.drawLine(m, n, x, y);

}

}

}