求各位解答，没有具体的思路

import java.awt.Dimension;

import javax.swing.JFrame;

public class ShootApp extends JFrame {

    public ShootApp() {
        setTitle("Shooting Game");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        getContentPane().setPreferredSize(new Dimension(500, 500));
        pack();

        GamePanel p = new GamePanel();
        setContentPane(p);
        setResizable(false);
        setVisible(true);

        p.startGame();
    }

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        new ShootApp();
    }

}
import java.awt.Color;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;

import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JPanel;

class TargetThread extends Thread {
    JLabel target = null;
    GamePanel panel = null;

    public TargetThread(GamePanel panel, JLabel target) {
        this.panel = panel;
        this.target = target;
    }

    @Override
    public void run() {
        // TODO Auto-generated method stub
        while (true) {
            int x = target.getX() + 5;
            int y = target.getY();

            if (x > panel.getWidth())
                target.setLocation(0, 0);
            else
                target.setLocation(x, y);

            target.getParent().repaint();

            try {
                sleep(50);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }

}

class BulletThread extends Thread {
    GamePanel panel = null;
    JLabel bullet = null;
    JLabel target = null;
    TargetThread tThread = null;

    public BulletThread(GamePanel panel, TargetThread tThread, JLabel target, JLabel bullet) {
        this.panel = panel;
        this.bullet = bullet;
        this.target = target;
        this.tThread = tThread;
    }

    public boolean hit() {
        return false;
    }

    @Override
    public void run() {
        // TODO Auto-generated method stub
        while (true) {
            if (hit() == true) {
                bullet.setLocation(panel.getWidth() / 2 - 10, panel.getHeight() - 70);

            } else {
                int x = bullet.getX();
                int y = bullet.getY() - 10;

                if (y + bullet.getHeight() < 0) {
                    bullet.setLocation(panel.getWidth() / 2 - 10, panel.getHeight() - 70);
                } else
                    bullet.setLocation(x, y);
            }
            target.getParent().repaint();
            try {
                sleep(30);
            } catch (InterruptedException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
}

class GamePanel extends JPanel {
    JLabel baseLabel = new JLabel();
    JLabel bulletLabel = new JLabel();
    JLabel targetLabel;
    TargetThread tThread = null;

    public GamePanel() {
        setLayout(null);
        setSize(500, 500);
        baseLabel.setSize(50, 50);
        baseLabel.setOpaque(true);
        baseLabel.setBackground(Color.BLACK);

        bulletLabel.setSize(20, 20);
        bulletLabel.setOpaque(true);
        bulletLabel.setBackground(Color.RED);

        ImageIcon img = new ImageIcon("targetImage.jpg");
        targetLabel = new JLabel(img);
        targetLabel.setSize(img.getIconWidth(), img.getIconHeight());

        add(baseLabel);
        add(bulletLabel);
        add(targetLabel);
    }

    public void startGame() {
        baseLabel.setLocation(this.getWidth() / 2 - 25, this.getHeight() - 50);
        bulletLabel.setLocation(this.getWidth() / 2 - 10, this.getHeight() - 70);
        targetLabel.setLocation(0, 0);

        tThread = new TargetThread(this, targetLabel);
        tThread.start();

        baseLabel.setFocusable(true);
        baseLabel.requestFocus();
        baseLabel.addKeyListener(new KeyAdapter() {
            BulletThread bThread = null;

            @Override
            public void keyPressed(KeyEvent e) {
                // TODO Auto-generated method stub
                if (e.getKeyChar() == '\n') {
                    if (bThread == null || !bThread.isAlive()) {
                        bThread = new BulletThread(GamePanel.this, tThread, targetLabel, bulletLabel);
                        bThread.start();
                    }
                }
            }

        });
    }

现在目标呗子弹击中 目标和子弹没有任何变化

如果目标被子弹击中，则必须包含目标和子弹返回起始位置的场景