如何在JFrame中实现图像重叠？多种尝试均未解决求助

我之前卡在了JFrame里实现图像重叠显示的问题上——试了单个JPanel、两个JPanel的方案都没成功，甚至用JLayeredPane也没达到预期效果。虽然涉及多个交互类，不确定代码能不能帮上忙，但还是把未完成的代码贴出来了：

import javax.swing.JLabel; 
import javax.swing.JFrame; 
import javax.swing.JPanel; 
import javax.swing.JLayeredPane; 
import javax.swing.ImageIcon; 
import java.awt.Graphics2D; 
import java.awt.Graphics; 
import java.awt.image.BufferedImage; 
import java.io.File; 
import javax.imageio.ImageIO; 
import java.io.IOException; 
import java.awt.event.KeyListener; 
import java.awt.event.KeyEvent; 

public class MazeDisplay implements KeyListener { 
    static JFrame window; 
    static JPanel backPanel, userPanel; 
    JLabel user, cpu, maze1, maze2; 
    User u; 

    public MazeDisplay(String x, Cell[][] maize1, Cell[][] maize2) throws IOException { 
        maze1 = new JLabel(new ImageIcon(createMazeImage(maize1))); 
        maze2 = new JLabel(new ImageIcon(createMazeImage(maize2))); 
        user = new JLabel(new ImageIcon("user.png")); 
        cpu = new JLabel(new ImageIcon("cpu.png")); 
        u = new User(maize1); 

        window = new JFrame(x); 
        window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
        window.setBounds(400, 400, 986, 509); 

        backPanel = (JPanel) window.getContentPane(); 
        backPanel.setLayout(null); 
        maze1.setBounds(0, 0, 480, 480); 
        maze2.setBounds(500, 0, 480, 480); 
        backPanel.add(maze1); 
        backPanel.add(maze2); 

        userPanel = new JPanel(null); 
        user.setBounds(0, 0, 30, 30); 
        cpu.setBounds(500, 0, 30, 30); 
        userPanel.add(user); 
        userPanel.add(cpu); 

        window.add(userPanel); 
        window.setResizable(false); 
        window.setVisible(true); 
    } 

    public void keyPressed(KeyEvent e) {} 
    public void keyReleased(KeyEvent e) {} 
    public void keyTyped(KeyEvent e) {} 

    public boolean isLegal(int dir) { 
        boolean ret = false; 
        Cell[][] maze = u.getMaize(); 
        if(0 <= u.xPos() && u.xPos() < maze.length && 0 <= u.yPos() && u.yPos() < maze.length) { 
            if(dir == 0) ret = (maze[u.xPos()][u.yPos()].isOpen(dir) && maze[u.xPos()][u.yPos()-1].isOpenO(dir)); 
            else if(dir == 1) ret = (maze[u.xPos()][u.yPos()].isOpen(dir) && maze[u.xPos()+1][u.yPos()].isOpenO(dir)); 
            else if(dir == 2) ret = (maze[u.xPos()][u.yPos()].isOpen(dir) && maze[u.xPos()][u.yPos()+1].isOpenO(dir)); 
            else if(dir == 3) ret = (maze[u.xPos()][u.yPos()].isOpen(dir) && maze[u.xPos()-1][u.yPos()].isOpenO(dir)); 
        } 
        return ret; 
    } 

    public static BufferedImage createMazeImage(Cell[][] maze) throws IOException { 
        BufferedImage[][] iMaze = new BufferedImage[maze.length][maze.length]; 
        for(int i = 0; i < iMaze.length; i++) 
            for(int j = 0; j < iMaze.length; j++) { 
                String cellDir = maze[i][j] + ".png"; 
                iMaze[i][j] = new BufferedImage(30, 30, BufferedImage.TYPE_INT_RGB); 
                Graphics2D icon = iMaze[i][j].createGraphics(); 
                icon.drawImage(ImageIO.read(new File(cellDir)), 0, 0, null); 
            } 

        int xOff = 0, yOff = 0; 
        BufferedImage mazeImage = new BufferedImage(maze.length * 30, maze.length * 30, BufferedImage.TYPE_INT_RGB); 
        Graphics2D g = mazeImage.createGraphics(); 
        for(int r = 0; r < iMaze.length; r++) { 
            for(int c = 0; c < iMaze.length; c++) { 
                g.drawImage(iMaze[r][c], xOff, yOff, null); 
                yOff += 30; 
            } 
            yOff = 0; 
            xOff += 30; 
        } 
        return mazeImage; 
    } 

    public static void main(String[] args) throws IOException { 
        MazeGen g = new MazeGen(16); 
        MazeGen h = new MazeGen(16); 
        MazeDisplay m = new MazeDisplay("Maze Game", g.getMaze(), h.getMaze()); 
    } 
} 

编辑：抱歉之前表述得有点模糊，当时状态很差又累又烦躁。不过还是特别感谢大家的帮助！最后我按照MadProgrammer的建议，改用GridBagLayout就顺利解决了图像重叠显示的问题。

内容的提问来源于stack exchange，提问作者androo