一个奇怪的有关问题，为什么小弟我画不出图片来

一个奇怪的问题，为什么我画不出图片来？

Java code

import java.awt.*;import java.awt.event.*;public class TankClient extends Frame{    private static int GAME_WIDTH = 800;    private static int GAME_HEIGHT = 600;        public static void main(String[] args) {        new TankClient().launchFrame();    }        Tank myTank = new Tank(50,50);              public void launchFrame(){        Frame f = new Frame();                  f.setBounds(222, 120, GAME_WIDTH, GAME_HEIGHT);        f.setBackground(Color.GREEN);        f.addWindowListener(new WindowAdapter(){            public void windowClosing(WindowEvent e){                System.exit(0);            }            });        f.setResizable(false);        f.setVisible(true);            }        public void paint(Graphics g) {        g.setColor(Color.GREEN);        g.fillOval(30, 30, 50, 50);    }}

Java code

import java.awt.*;import java.awt.event.*;public class TankClient extends Frame{    private static int GAME_WIDTH = 800;    private static int GAME_HEIGHT = 600;        public static void main(String[] args) {        new TankClient();    }        //Tank myTank = new Tank(50,50);              public TankClient(){        //Frame f = new Frame();        setBounds(222, 120, GAME_WIDTH, GAME_HEIGHT);        setBackground(Color.GREEN);        addWindowListener(new WindowAdapter(){            public void windowClosing(WindowEvent e){                System.exit(0);            }            });        setResizable(false);        setVisible(true);            }        public void paint(Graphics g) {        g.setColor(Color.RED);        g.fillOval(30, 30, 50, 50);    }}