Drawing many particles in a loop doesn't work.

[vitali.pom]

Here is an example of my problem, this code does draw:

public static void paint(Graphics g, Ball2 balls, int startX,int imWidth, int endY, Image img, Object ths ){        
        for(int i = 0;i<balls.getBallPositionsArr().length/2;i++){                                 
             //g.setColor (0xffffcc);
             //g.fillRoundRect( (int)(balls.getX(i) - balls.getRadius())-2, (int)(balls.getY(i) - balls.getRadius())-2, (int) balls.getRadius()+4, (int) balls.getRadius()+4,1,1);                                         
             g.setColor (0xffffcc); 
             g.fillRect(20, 20, 50, 10);
        }
             g.setColor (0xffffcc); 
             g.fillRect(20, 20, 50, 10);                          
}

while this doesn't:

public static void paint(Graphics g, Ball2 balls, int startX,int imWidth, int endY, Image img, Object ths ){        
        for(int i = 0;i<balls.getBallPositionsArr().length/2;i++){                                 
             //g.setColor (0xffffcc);
             //g.fillRoundRect( (int)(balls.getX(i) - balls.getRadius())-2, (int)(balls.getY(i) - balls.getRadius())-2, (int) balls.getRadius()+4, (int) balls.getRadius()+4,1,1);                                         
             g.setColor (0xffffcc); 
             g.fillRect(20, 20, 50, 10);
        }                   
}

Why the last piece of code, which shall draw to "g" in a loop doesn't do what's expected? How can I fix it?
In Java SE both work.

[skalogir]

Hi,

Can you try to get the value of

balls.getBallPositionsArr().length/2

when you run your program?
It could be that for some reason, this expression is evaluated to 0 and that could force your program to skip entirely the "for" loop.

[vitali.pom]

Indeed, the value was 0.
Thank you.