Java tutorial
import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.RoundRectangle2D; public class Main extends javax.swing.JFrame { public Main() { setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); setSize(600, 600); } public void paint(Graphics g) { Graphics2D graphics2 = (Graphics2D) g; RoundRectangle2D roundedRectangle = new RoundRectangle2D.Float(100, 100, 240, 160, 10, 10); graphics2.draw(roundedRectangle); } public static void main(String args[]) { new Main().setVisible(true); } }