java program that print circles in circles

This is main class

package graphs;
import javax.swing.*;
public class Graphs {

   
    public static void main(String[] args) {
       String title="ALLAH IS ONE";
      
       JFrame f= new JFrame();
       f.setSize(700,700);
       f.setTitle(title);
       paints P= new paints();
       f.add(P);
       f.setVisible(true);
      f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    }
   
}

After writing main class create a class of paints and call it in main class

package graphs;
import javax.swing.*;
import java.awt.*;
import java.awt.geom.*;

public class paints extends JComponent {
      public void paint(Graphics g)
    {
                Graphics2D g2 = (Graphics2D) g;
      
           int a=16,s=30,d=400,f=400;
               for(int i=0;i<14;i++)
               {
                  Ellipse2D.Double R= new Ellipse2D.Double(a,s,d,f);
                  g2.draw(R);
                  if(i%2==0)
                  {  g2.setColor(Color.BLACK);
                      g2.fill(R);
                  }
                  else
                  {    g2.setColor(Color.red);
                      g2.fill(R);
                  }
                  a+=14;s+=14;d-=30;f-=30;
         
    }}
}

Output is