How can i make a wheels rotate/flip

look i'm attempt to make a car moving, and i'm tring to use g2d to rotate a rectangle for example just to understands how can i make the wheels rotate/flip, so look at that code:

Code:

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import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class RotateTest extends JPanel {
 Timer timer;
 int x = 1;
 public RotateTest(){
  ActionListener task = new ActionListener(){
  @Override
  public void actionPerformed(ActionEvent ae) {
    x += 1;
    repaint();
  }};
  timer = new Timer(25, task);
  timer.start();
 }
 @Override
 public void paint(Graphics g){
  super.paint(g);
        Graphics2D g2d = (Graphics2D) g;
 
        g2d.setColor(new Color(150, 150, 150));
        g2d.fillRect(20, 20, 80, 50);
        g2d.translate(180, -50);
        g2d.rotate(Math.PI/x);
        g2d.fillRect(80, 80, 80, 50);
       
 }
 
 
 public static void main(String[] args) {
        JFrame frame = new JFrame("Rotation");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(new RotateTest());
        frame.setSize(300, 200);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
}

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Now someone car help me with this, beacuse when you run that code the right rectangle is flip in circle and not in his specific place without change no x or y,
Can you fix the code for me? or give me an another option to make this?

thanks :)