Java AWT Graphics2D transform rotate

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;
import java.util.Random;

import javax.swing.JFrame;
import javax.swing.JPanel;

public class Main extends JPanel {
  Random rnd = new Random();

  @Override/*from w  w w . j a va 2  s.  co  m*/
  public void paintComponent(Graphics g) {
    super.paintComponent(g);

    Graphics2D g2d = (Graphics2D) g;
    g2d.setBackground(Color.WHITE);
    g2d.clearRect(0, 0, getParent().getWidth(), getParent().getHeight());
    // antialising
    g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

    // save transform
    AffineTransform origTransform = g2d.getTransform();

    g2d.setPaint(Color.BLACK);
    g2d.setStroke(new BasicStroke(3f));

    // Rectangle2D (original)
    Rectangle2D rectangle = new Rectangle2D.Float(50, 50, 50, 50);
    g2d.draw(rectangle);

    // Shearing
    AffineTransform shear = new AffineTransform();

    // move to upper right
    shear.translate(rectangle.getX() + rectangle.getWidth() + 50, 0);

    shear.shear(-.5, 0);

    g2d.transform(shear);
    g2d.draw(rectangle);

    g2d.setTransform(origTransform);

    // rotate
    AffineTransform rotate = new AffineTransform();

    // move to bottom left
    rotate.translate(0, rectangle.getY() + rectangle.getHeight());

    rotate.rotate(Math.PI / 4, rectangle.getCenterX(), rectangle.getCenterY());

    g2d.transform(rotate);
    g2d.draw(rectangle);

    g2d.setTransform(origTransform);

    // scale
    AffineTransform scale = new AffineTransform();

    // move to bottom right
    scale.translate(rectangle.getX() + 30, rectangle.getY());

    // scale
    scale.scale(1.5, 1.5);

    g2d.transform(scale);
    g2d.draw(rectangle);
  }

  public static void main(String[] args) {
    // create frame for Main
    JFrame frame = new JFrame("java2s.com");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    Main Main = new Main();
    frame.add(Main);
    frame.setSize(300, 210);
    frame.setVisible(true);
  }
}