import javax.swing.*;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.*;

public class Graphics2DTest2 extends JPanel{

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

    Graphics2DTest2 app = new Graphics2DTest2();
    frame.getContentPane().add(app);

    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setBounds(10, 10, 300, 200);
    frame.setTitle("ƒ^ƒCƒgƒ‹");
    frame.setVisible(true);
  }

  public void paintComponent(Graphics g){
    Graphics2D g2 = (Graphics2D)g;

    g2.draw(new Line2D.Double(20, 20, 160, 140));
  }
}