how to create a rectangle in java

1import javax.swing.JFrame;
2import java.awt.Rectangle;
3import javax.swing.JComponent;
4import java.awt.Graphics2D;
5import java.awt.Graphics;
6import java.awt.Color;
7
8public class ChrismasTree {
9    public static void main(String[] args) {
10        JFrame window = new JFrame();
11        window.setTitle("Christmas Tree");
12        window.setSize(800, 1000);
13        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
14        window.setVisible(true);
15        DrawingComponent DC = new DrawingComponent();
16        window.add(DC);
17    }
18}
19
20class DrawingComponent extends JComponent{
21    public void paint(Graphics graph0){
22        Graphics2D graph = (Graphics2D) graph0;
23
24        graph.setColor(Color.LIGHT_GRAY);
25        graph.draw(new Rectangle(0, 710, 70, 60));
26
27        graph.setColor(Color.BLUE);
28        graph.draw(new Rectangle(70, 600, 50, 100));
29
30        graph.setColor(Color.BLACK);
31    }
32}