java 회전 매트릭스

import javax.swing.*;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Insets;
import java.awt.geom.Line2D;

public class Graphics2DTest1 extends JPanel{
    double x = 1;
    double y = 400;

    double r = 100;
    double cx, cy;
    double rx,ry;


    double movex;
    double movey;

    double theta = 30;

  public static void main(String[] args){
    JFrame frame = new JFrame();

    Graphics2DTest1 app = new Graphics2DTest1();
    frame.setBackground(Color.BLACK); 
    frame.getContentPane().add(app);
    frame.setResizable(false);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setBounds(0, 0, 400, 400);
    frame.setTitle("タイトル");
    frame.setVisible(true);
    Insets insets = frame.getInsets();
    frame.setSize(400 + insets.left + insets.right, 400 + insets.top + insets.bottom);
  }

  public void paintComponent(Graphics g){
     Graphics2D g2 = (Graphics2D)g;
     g.setColor(Color.white);
     g.drawLine(0,200,400,200);
     g.drawLine(200,0,200,400);
     //array(g);
     //Circle(g);
     //oval(g);
     rotation(g2);
  }

  public void array(Graphics2D g){
      for(int i = 0; i <= 400; i++){
          g.draw(new Line2D.Double(x + i ,y - i,x + i,y - i));
          movex += 1;
          movey -= 1;
      }
   }


  public void Circle(Graphics2D g){
      for(int i = 0; i < 360; i++){
          cy = (int) (200 + Math.sin(i) * r);
          cx = (int) (200 + Math.cos(i) * r);
          g.draw(new Line2D.Double(cx, cy, cx, cy));
      }
  }

  public void oval(Graphics2D g){
      for(int i = 0; i < 360; i++){
          cy = (int) (200 + Math.sin(i) * r / 2);
          cx = (int) (200 + Math.cos(i) * r);
          g.draw(new Line2D.Double(cx, cy, cx, cy));
      }
  }

  public void rotation(Graphics2D g){
      g.setColor(Color.yellow);
      for(int i = 0; i < 12; i++){
          double rx = 200 + (r * Math.cos((theta * i) / 180 * Math.PI));
          double ry = 200 + (r * Math.sin((theta * i) / 180 * Math.PI));
          g.draw(new Line2D.Double(rx, ry, rx, ry));
      //g2.draw(new Line2D.Double(x, y, x, y));
          System.out.println(i + "回目");
          System.out.println("rx" + rx);
          System.out.println("ry" + ry);
      }
   }
}