Draw polygon in Java

//from w  ww  .j  a  va 2s  .  co  m
import java.awt.Graphics;

import javax.swing.JComponent;
import javax.swing.JFrame;

class MyCanvas extends JComponent {
  public void paint(Graphics g) {
    int[] x = new int[]{100,200,300,400};
    int[] y = new int[]{400,300,300,100};
    g.drawPolygon (x, y, x.length);  

  }
}

public class Main {
  public static void main(String[] a) {
    JFrame window = new JFrame();
    window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    window.setBounds(30, 30, 450, 450);
    window.getContentPane().add(new MyCanvas());
    window.setVisible(true);
  }
}