Олимпийские кольца

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.util.ArrayList;
import java.util.List;
 
import javax.swing.JFrame;
import javax.swing.JPanel;
 
public class Olympic extends JFrame {
    private static final long serialVersionUID = 1L;
    private static final int THICKNESS = 5;
 
    Olympic() {
        setSize(500, 300);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLocationRelativeTo(null);
        drawOlympicSymbol();
        setVisible(true);
    }
 
    private void drawOlympicSymbol() {
        List<Circle> circleList = new ArrayList<Circle>();
        int width = getSize().width;
        int portion = width / 4;
        int radius = portion;
        portion /= 2;
        Circle blueCircle = new Circle(portion, portion, radius, THICKNESS,
                Color.BLUE);
        circleList.add(blueCircle);
 
        int blackStartPosition = blueCircle.x + radius;
        Circle blackCircle = new Circle(blackStartPosition, portion, radius,
                THICKNESS, Color.BLACK);
        circleList.add(blackCircle);
        add(new CirclePanel(circleList));
 
        int redStartPosition = blackCircle.x + radius;
        Circle redCircle = new Circle(redStartPosition, portion, radius,
                THICKNESS, Color.RED);
        circleList.add(redCircle);
 
        int yellowStartPositionX = width / 6;
        int yellowStartPositionY = blueCircle.y + radius - 3;
        Circle yellowCircle = new Circle(yellowStartPositionX * 3,
                yellowStartPositionY, radius, THICKNESS, Color.YELLOW);
        circleList.add(yellowCircle);
 
        Circle greenCircle = new Circle(yellowCircle.x - radius,
                yellowStartPositionY, radius, THICKNESS, Color.GREEN);
        circleList.add(greenCircle);
    }
 
    public static void main(String[] args) {
        new Olympic();
    }
 
    private class CirclePanel extends JPanel {
        List<Circle> circleList;
 
        CirclePanel(List<Circle> circleList) {
            this.circleList = circleList;
        }
 
        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2d = (Graphics2D) g;
            for (Circle circle : circleList) {
                g2d.setStroke(new BasicStroke(circle.thickness));
                g2d.setColor(circle.color);
                g2d.drawOval(circle.x, circle.y, circle.radius, circle.radius);
            }
        }
    }
 
    private class Circle {
        private int x, y, radius, thickness;
        private Color color;
 
        Circle(int x, int y, int radius, int thickness, Color color) {
            this.x = x;
            this.y = y;
            this.radius = radius;
            this.thickness = thickness;
            this.color = color;
        }
    }
}