Paint & Graphics in Java

Class No.1
package FreeFlow;

import java.awt.Graphics;

import javax.swing.JPanel;

import java.awt.Color;
import java.awt.Dimension;

public class Dots extends JPanel {

public Dots() {
setBackground(Color.PINK);
setPreferredSize(new Dimension(400, 400));
}


public void paintComponent(Graphics g) {
super.paintComponent(g);

g.drawRect(0, 0, 400, 400);
g.setColor(Color.BLACK);
g.drawLine(0, 200, 400, 200);
g.setColor(Color.BLUE);
g.drawLine(200, 0, 200,400);

g.fillRect(10, 10, 180, 180);
g.setColor(Color.WHITE);
g.drawArc(10, 10, 179, 179, 0, 360);
g.setColor(Color.ORANGE);
g.drawArc(20, 20, 160, 160, 0, 360);
g.setColor(Color.WHITE);
g.drawArc(30, 30, 140, 140, 0, 360);
g.setColor(Color.ORANGE);
g.drawArc(40, 40, 120, 120, 0, 360);
g.setColor(Color.ORANGE);
g.drawArc(50, 50, 100, 100, 0, 360);
g.setColor(Color.WHITE);
g.drawArc(60, 60, 80, 80, 0, 360);
g.setColor(Color.YELLOW);
g.fillArc(80, 80, 40, 40, 0, 360);
g.setColor(Color.BLACK);
g.fillArc(90, 90, 20, 20, 0, 360);


//g.fillRect(110, 110, 180, 180);
//
g.fillRect(210, 210, 180, 180);
g.setColor(Color.WHITE);
g.drawArc(210, 210, 179, 179, 0, 360);
g.setColor(Color.ORANGE);
g.drawArc(220, 220, 160, 160, 0, 360);
g.setColor(Color.WHITE);
g.drawArc(230, 230, 140, 140, 0, 360);
g.setColor(Color.ORANGE);
g.drawArc(240, 240, 120, 120,0,360 );
g.setColor(Color.ORANGE);
g.drawArc(250, 250, 100, 100, 0, 360);
g.setColor(Color.WHITE);
g.drawArc(260, 260, 80, 80, 0, 360);
g.setColor(Color.YELLOW);
g.fillArc(280, 280, 40, 40, 0, 360);
g.setColor(Color.BLACK);
g.fillArc(290, 290, 20, 20, 0, 360);

//
g.setColor(Color.WHITE);
g.drawLine(200, 200, 0, 400);
g.drawLine(0, 200, 200, 400);
g.setColor(Color.GRAY);
g.fillRoundRect(75, 220, 50, 50, 15, 15);
g.fillRoundRect(75, 330, 50, 50, 15, 15);
g.setColor(Color.RED);
g.fillRoundRect(140, 275, 50, 50, 15, 15);
g.fillRoundRect(10, 275, 50, 50, 15, 15);

//
g.draw3DRect(210, 10, 180, 180, true);
g.draw3DRect(210, 10, 170, 170, false);
g.draw3DRect(210, 10, 160, 160, true);
g.draw3DRect(210, 10, 150, 150, false);
g.draw3DRect(210, 10, 140, 140, true);
g.draw3DRect(210, 10, 130, 130, false);
g.draw3DRect(210, 10, 120, 120, true);
g.draw3DRect(210, 10, 110, 110, false);
g.draw3DRect(210, 10, 100, 100, true);
g.draw3DRect(210, 10, 90, 90, false);
g.draw3DRect(210, 10, 80, 80, true);
g.draw3DRect(210, 10, 70, 70, false);

}



}

Class No.2
package FreeFlow;

import java.awt.BorderLayout;
import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;

public class MainFrame extends JFrame {

private Dots contentPane;

/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
MainFrame frame = new MainFrame();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}

/**
* Create the frame.
*/
public MainFrame() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(400, 400, 400, 400);
contentPane = new Dots();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(new BorderLayout(0, 0));
pack();
}

}