事情是这样的，我们班有一个作业要做一个JAVA走迷宫的游戏，然后我就在网上找了这段代码，可是老师还要我们解释这段代码，我完全看不懂，所以可以麻烦各位大神帮我详细解释一下吗，谢谢了
package qw;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.util.Random;
import java.util.Stack;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
class Lattice {
static final int INTREE = 1;
static final int NOTINTREE = 0;
private int x = -1;
private int y = -1;
private int flag = NOTINTREE;
private Lattice father = null;
public Lattice(int xx, int yy) {
x = xx;
y = yy;
}
public int getX() {
return x;
}
public int getY() {
return y;
}
public int getFlag() {
return flag;
}
public Lattice getFather() {
return father;
}
public void setFather(Lattice f) {
father = f;
}
public void setFlag(int f) {
flag = f;
}
public String toString() {
return new String("(" + x + "," + y + ")\n");
}
}
public class maze extends JPanel {
private static final long serialVersionUID = -8300339045454852626L;
private int NUM, width, padding;// width 每个格子的宽度和高度
private Lattice[][] maze;
private int ballX, ballY;
private boolean drawPath = false;
maze(int m, int wi, int p) {
NUM = m;
width = wi;
padding = p;
maze = new Lattice[NUM][NUM];
for (int i = 0; i <= NUM - 1; i++)
for (int j = 0; j <= NUM - 1; j++)
maze[i][j] = new Lattice(i, j);
createMaze();
setKeyListener();
this.setFocusable(true);
}
private void init() {
for (int i = 0; i <= NUM - 1; i++)
for (int j = 0; j <= NUM - 1; j++) {
maze[i][j].setFather(null);
maze[i][j].setFlag(Lattice.NOTINTREE);
}
ballX = 0;
ballY = 0;
drawPath = false;
createMaze();
// setKeyListener();
this.setFocusable(true);
repaint();
}
public int getCenterX(int x) {
return padding + x * width + width / 2;
}
public int getCenterY(int y) {
return padding + y * width + width / 2;
}
public int getCenterX(Lattice p) {
return padding + p.getY() * width + width / 2;
}
public int getCenterY(Lattice p) {
return padding + p.getX() * width + width / 2;
}
private void checkIsWin() {
if (ballX == NUM - 1 && ballY == NUM - 1) {
JOptionPane.showMessageDialog(null, "YOU WIN !", "你走出了迷宫。",
JOptionPane.PLAIN_MESSAGE);
init();
}
}
synchronized private void move(int c) {
int tx = ballX, ty = ballY;
// System.out.println(c);
switch (c) {
case KeyEvent.VK_LEFT :
ty--;
break;
case KeyEvent.VK_RIGHT :
ty++;
break;
case KeyEvent.VK_UP :
tx--;
break;
case KeyEvent.VK_DOWN :
tx++;
break;
case KeyEvent.VK_SPACE :
if (drawPath == true) {
drawPath = false;
} else {
drawPath = true;
}
break;
default :
}
if (!isOutOfBorder(tx, ty)
&& (maze[tx][ty].getFather() == maze[ballX][ballY]
|| maze[ballX][ballY].getFather() == maze[tx][ty])) {
ballX = tx;
ballY = ty;
}
}
private void setKeyListener() {
this.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent e) {
int c = e.getKeyCode();
move(c);
repaint();
checkIsWin();
}
});
}
private boolean isOutOfBorder(Lattice p) {
return isOutOfBorder(p.getX(), p.getY());
}
private boolean isOutOfBorder(int x, int y) {
return (x > NUM - 1 || y > NUM - 1 || x < 0 || y < 0) ? true : false;
}
private Lattice[] getNeis(Lattice p) {
final int[] adds = {-1, 0, 1, 0, -1};// 顺序为上右下左
if (isOutOfBorder(p)) {
return null;
}
Lattice[] ps = new Lattice[4];// 顺序为上右下左
int xt;
int yt;
for (int i = 0; i <= 3; i++) {
xt = p.getX() + adds[i];
yt = p.getY() + adds[i + 1];
if (isOutOfBorder(xt, yt))
continue;
ps[i] = maze[xt][yt];
}
return ps;
}
private void createMaze() {
Random random = new Random();
int rx = Math.abs(random.nextInt()) % NUM;
int ry = Math.abs(random.nextInt()) % NUM;
Stack<Lattice> s = new Stack<Lattice>();
Lattice p = maze[rx][ry];
Lattice neis[] = null;
s.push(p);
while (!s.isEmpty()) {
p = s.pop();
p.setFlag(Lattice.INTREE);
neis = getNeis(p);
int ran = Math.abs(random.nextInt()) % 4;
for (int a = 0; a <= 3; a++) {
ran++;
ran %= 4;
if (neis[ran] == null || neis[ran].getFlag() == Lattice.INTREE)
continue;
s.push(neis[ran]);
neis[ran].setFather(p);
}
}
// changeFather(maze[0][0],null);
}
private void changeFather(Lattice p, Lattice f) {
if (p.getFather() == null) {
p.setFather(f);
return;
} else {
changeFather(p.getFather(), p);
}
}
private void clearFence(int i, int j, int fx, int fy, Graphics g) {
int sx = padding + ((j > fy ? j : fy) * width),
sy = padding + ((i > fx ? i : fx) * width),
dx = (i == fx ? sx : sx + width),
dy = (i == fx ? sy + width : sy);
if (sx != dx) {
sx++;
dx--;
} else {
sy++;
dy--;
}
g.drawLine(sx, sy, dx, dy);
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
for (int i = 0; i <= NUM; i++) {
g.drawLine(padding + i * width, padding, padding + i * width,
padding + NUM * width);
}
for (int j = 0; j <= NUM; j++) {
g.drawLine(padding, padding + j * width, padding + NUM * width,
padding + j * width);
}
g.setColor(this.getBackground());
for (int i = NUM - 1; i >= 0; i--) {
for (int j = NUM - 1; j >= 0; j--) {
Lattice f = maze[i][j].getFather();
if (f != null) {
int fx = f.getX(), fy = f.getY();
clearFence(i, j, fx, fy, g);
}
}
}
g.drawLine(padding, padding + 1, padding, padding + width - 1);
int last = padding + NUM * width;
g.drawLine(last, last - 1, last, last - width + 1);
g.setColor(Color.RED);
g.fillOval(getCenterX(ballY) - width / 3, getCenterY(ballX) - width / 3,
width / 2, width / 2);
}
public static void main(String[] args) {
final int n = 30, width = 600, padding = 20, LX = 200, LY = 100;
JPanel p = new maze(n, (width - padding - padding) / n, padding);
JFrame frame = new JFrame("MAZE");
frame.getContentPane().add(p);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(width + padding, width + padding + padding);
frame.setLocation(LX, LY);
frame.setVisible(true);
}
}