一、效果展示

二、代码编写

1. 素材准备

首先创建一个基本的 java 项目，并将本游戏需要用到的图片素材 image 导入。

图片素材如下：
https://pan.baidu.com/s/1db_IcPvPKWKbVPtodPWO5Q?pwd=03kv
提取码：03kv

2. 创建窗口类

① Java 内部已经给我们封装了窗口的各种方法，我们只需创建一个窗口类并重写父类的方法，即可使用；
② Alt + Enter 键 → implement methods 可一键补全所有的重写方法；
③ 实现多线程有两种方法，分别是继承 Thread 类和实现 Runnable 接口，这里我们用 Runnable 方法，因为 Java 不支持多继承。

重写 paint 方法，实现场景、物体的绘制，使用多线程无限绘制窗口。

完整代码如下：

package com.zxe.beans;

import javax.swing.*;
import java.awt.*;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.ArrayList;
import java.util.List;

/**
 * 窗口类
 */
public class MyFrame extends JFrame implements KeyListener, Runnable {

    //定义一个集合用于所有的关卡
    private List<LevelMap> levelMaps = new ArrayList<>();
    //定义一个变量，存放当前背景
    private LevelMap levelMap = new LevelMap();
    //定义变量，记录马里奥
    private Mario mario;

    //重写paint方法，实现场景、物体的绘制
    @Override
    public void paint(Graphics g) {
        //创建一张图片
        Image image = createImage(1045, 500);
        //设置图片
        Graphics graphics = image.getGraphics();
        graphics.drawImage(levelMap.getBg(), 0, 0, 1045, 500, this);
        //绘制障碍物
        for (Obstacle obstacle : levelMap.getObstacles()){
            graphics.drawImage(obstacle.getObstacleImage(), obstacle.getX(), obstacle.getY(), this);
        }
        //绘制马里奥
        graphics.drawImage(mario.getMarioImage(), mario.getX(), mario.getY(), this);

        //将图片描绘到当前窗口中
        g.drawImage(image, 0, 0, this);
    }

    @Override
    public void keyTyped(KeyEvent e) {

    }

    @Override
    public void keyPressed(KeyEvent e) {
        if (e.getKeyCode() == 37) {
            mario.runLeft();
        } else if (e.getKeyCode() == 39) {
            mario.runRight();
        } else if (e.getKeyCode() == 38) {
            mario.jump();
        }
    }

    public Mario getMario() {
        return mario;
    }

    public void setMario(Mario mario) {
        this.mario = mario;
    }

    @Override
    public void keyReleased(KeyEvent e) {
        if (e.getKeyCode() == 37) {
            mario.runLeftStop();
        } else if (e.getKeyCode() == 39) {
            mario.runRightStop();
        } else if (e.getKeyCode() == 38) {
            mario.jumpDown();
        }
    }

    @Override
    public void run() {
        //无限次绘制马里奥
        while (true) {
            repaint();
            try {
                Thread.sleep(50);
            } catch (InterruptedException e) {
                throw new RuntimeException(e);
            }
            //判断一下马里奥是否通关
            if (mario.getX() > 1040) {
                levelMap = levelMaps.get(levelMap.getLevel());
                mario.setLevelMap(levelMap);
                mario.setX(50);
                mario.setY(420);
            }
        }
    }

    public List<LevelMap> getLevelMaps() {
        return levelMaps;
    }

    public void setLevelMaps(List<LevelMap> levelMaps) {
        this.levelMaps = levelMaps;
    }

    public LevelMap getLevelMap() {
        return levelMap;
    }

    public void setLevelMap(LevelMap levelMap) {
        this.levelMap = levelMap;
    }
}

3. 创建常量类

小游戏中的各种元素画面其实都是一张张的图片，而这些图片路径的定义都将放在常量类中完成。

package com.zxe.beans;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

/**
 * 常量类
 */
public class Constant {
    //给窗口定义一张图片
    public static BufferedImage bg;
    //右跳图片
    public static BufferedImage jumpR;
    //左跳图片
    public static BufferedImage jumpL;
    //右边站立
    public static BufferedImage standR;
    //左边站立
    public static BufferedImage standL;
    //定义一个集合，存放右跑动作
    public static List<BufferedImage> runR = new ArrayList<>();
    //定义一个集合，存放左跑动作
    public static List<BufferedImage> runL = new ArrayList<>();
    //为障碍物定义一个集合
    public static List<BufferedImage> onstacles = new ArrayList<>();

    //定义一个变量，记录文件路径前缀
    public static String prefix = "C:\\Users\\Lenovo\\Desktop\\demo\\file\\image\\";

    //初始化图片到系统中
    public static void initImage() {
        try {
            //加载图片
            bg = ImageIO.read(new File(prefix + "bg2.jpeg"));
            jumpR = ImageIO.read(new File(prefix + "mario_jump_r.png"));
            jumpL = ImageIO.read(new File(prefix + "mario_jump_l.png"));
            standR = ImageIO.read(new File(prefix + "mario_stand_r.png"));
            standL = ImageIO.read(new File(prefix + "mario_stand_l.png"));
            runR.add(ImageIO.read(new File(prefix + "mario_run_r1.png")));
            runR.add(ImageIO.read(new File(prefix + "mario_run_r2.png")));
            runL.add(ImageIO.read(new File(prefix + "mario_run_l1.png")));
            runL.add(ImageIO.read(new File(prefix + "mario_run_l2.png")));
            for (int i = 1; i <= 6; i++) {
                onstacles.add(ImageIO.read(new File(prefix + "ob" + i + ".png")));
            }
        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException(e);
        }
    }

}

常量用 static 修饰，外部可直接通过类名调用常量，而无需创建对象。

4. 创建动作类

记录玛丽的动作状态，具体的常量名与代码分离，可以降低代码的耦合度，更规范化。

5. 创建关卡类

每个关卡的障碍物是不一样的，这里需要外部传入关卡号，在关卡类中把不同的障碍物拼成自定义的关卡。

完整代码如下：

package com.zxe.beans;

import com.zxe.utils.Constant;

import java.awt.image.BufferedImage;
import java.util.ArrayList;
import java.util.List;

/**
 * 关卡地图类
 */
public class LevelMap {
    //记录当前场景需要的图片
    private BufferedImage bg;
    //记录当前关卡
    private int level;
    //创建一个集合，用于存放障碍物
    private List<Obstacle> obstacles = new ArrayList<>();

    public LevelMap() {
    }

    public LevelMap(int level) {
        this.level = level;
        bg = Constant.bg;
        if (level == 1) {
            //绘制方块
            obstacles.add(new Obstacle(100, 370, 0, this));
            obstacles.add(new Obstacle(130, 370, 1, this));
            obstacles.add(new Obstacle(160, 370, 0, this));
            obstacles.add(new Obstacle(190, 370, 1, this));
            obstacles.add(new Obstacle(300, 260, 0, this));
            obstacles.add(new Obstacle(330, 260, 1, this));
            obstacles.add(new Obstacle(360, 260, 1, this));
            obstacles.add(new Obstacle(800, 300, 0, this));
            obstacles.add(new Obstacle(830, 300, 0, this));
            obstacles.add(new Obstacle(860, 300, 1, this));
            obstacles.add(new Obstacle(890, 300, 1, this));
            //绘制水管
            obstacles.add(new Obstacle(420, 420, 4, this));
            obstacles.add(new Obstacle(450, 420, 5, this));
            obstacles.add(new Obstacle(415, 390, 2, this));
            obstacles.add(new Obstacle(435, 390, 2, this));
            obstacles.add(new Obstacle(455, 390, 3, this));
            obstacles.add(new Obstacle(600, 420, 4, this));
            obstacles.add(new Obstacle(630, 420, 5, this));
            obstacles.add(new Obstacle(600, 390, 4, this));
            obstacles.add(new Obstacle(630, 390, 5, this));
            obstacles.add(new Obstacle(595, 360, 2, this));
            obstacles.add(new Obstacle(615, 360, 2, this));
            obstacles.add(new Obstacle(635, 360, 3, this));

        } else if (level == 2) {
            int i = 0;
            for (int y = 420; y >= 300; y -= 30) {
                for (int x = 100; x <= 190 - 30 * i; x += 30) {
                    obstacles.add(new Obstacle(x + 30 * i, y, 0, this));
                }
                for (int x = 300; x <= 390 - 30 * i; x += 30) {
                    obstacles.add(new Obstacle(x, y, 0, this));
                }
                for (int x = 550; x <= 640 - 30 * i; x += 30) {
                    obstacles.add(new Obstacle(x + 30 * i, y, 0, this));
                }
                for (int x = 670; x <= 790 - 30 * i; x += 30) {
                    obstacles.add(new Obstacle(x, y, 0, this));
                }
                i++;
            }
        }
    }

    public BufferedImage getBg() {
        return bg;
    }

    public void setBg(BufferedImage bg) {
        this.bg = bg;
    }

    public int getLevel() {
        return level;
    }

    public void setLevel(int level) {
        this.level = level;
    }

    public List<Obstacle> getObstacles() {
        return obstacles;
    }

    public void setObstacles(List<Obstacle> obstacles) {
        this.obstacles = obstacles;
    }
}

6. 创建障碍物类

障碍物的属性包括图片以及横纵坐标。

完整代码如下：

package com.zxe.beans;

import com.zxe.utils.Constant;

import java.awt.image.BufferedImage;

/**
 * 障碍物类
 */
public class Obstacle {
    //记录障碍物的坐标
    private int x;
    private int y;
    //定义一个变量，记录当前障碍物的图片信息
    private BufferedImage obstacleImage;
    //定义障碍物类型
    private int type;
    //定义变量存放当前的背景
    private LevelMap bg;

    public Obstacle(int x, int y, int type, LevelMap bg) {
        this.x = x;
        this.y = y;
        this.type = type;
        this.bg = bg;
        //根据障碍物的编号，从常量中的障碍物集合中获取对应的图片
        this.obstacleImage = Constant.onstacles.get(type);
    }

    public int getX() {
        return x;
    }

    public void setX(int x) {
        this.x = x;
    }

    public int getY() {
        return y;
    }

    public void setY(int y) {
        this.y = y;
    }

    public BufferedImage getObstacleImage() {
        return obstacleImage;
    }

    public void setObstacleImage(BufferedImage obstacleImage) {
        this.obstacleImage = obstacleImage;
    }

    public int getType() {
        return type;
    }

    public void setType(int type) {
        this.type = type;
    }

    public LevelMap getBg() {
        return bg;
    }

    public void setBg(LevelMap bg) {
        this.bg = bg;
    }
}

7. 创建马里奥类

马里奥的无限行走动作由多线程实现，定义一个状态量status，用于标记马里奥当前的运动状态，以便进行不同动作的来回切换。

完整代码如下：

package com.zxe.beans;

import com.zxe.utils.Action;
import com.zxe.utils.Constant;

import java.awt.image.BufferedImage;

/**
 * 马里奥类
 */
public class Mario implements Runnable {
    //记录马里奥坐标信息
    private  int x;
    private int y;
    //记录马里奥状态
    private String status;
    //定义一个变量，记录马里奥当前动作所对应的图片信息
    private BufferedImage marioImage;
    //定义变量，记录当前的关卡地图，也可以获取障碍物的信息
    private LevelMap levelMap = new LevelMap();

    //创建线程执行马里奥的动作
    private Thread thread;
    //定义变量，记录马里奥的移动速度
    private int xSpeed;
    //定义变量，记录马里奥的跳跃速度
    private int ySpeed;
    //定义变量，记录马里奥的上升状态
    private int up;

    public Mario() {}

    public Mario(int x, int y) {
        this.x = x;
        this.y = y;
        //默认马里奥的动作是朝右站立
        status = Action.STAND_RIGHT;
        marioImage = Constant.standR;
        thread = new Thread(this);
        thread.start();
    }

    //马里奥向左移动的方法
    public void runLeft() {
        //判断当前是否为跳跃状态，如果不是，就改变状态
        if ( !status.contains("jump") ) {
            status = Action.RUN_LEFT;
        } else {
            status = Action.JUMP_LEFT;
        }
        xSpeed = -5;
    }

    //马里奥向右移动的方法
    public void runRight() {
        //判断当前是否为跳跃状态，如果不是，就改变状态
        if ( !status.contains("jump") ) {
            status = Action.RUN_RIGHT;
        } else {
            status = Action.JUMP_RIGHT;
        }
        xSpeed = 5;
    }

    public void jump() {
        if (status.contains("left")) {
            status = Action.JUMP_LEFT;
        } else {
            status = Action.JUMP_RIGHT;
        }
            ySpeed = -12;
    }

    public void jumpDown() {
        ySpeed = 12;
    }

    private void jumpStop() {
        if (status.contains("left")) {
            status = Action.STAND_LEFT;
        } else {
            status = Action.STAND_RIGHT;
        }
        ySpeed = 0;
    }

    //马里奥向左移动停止的方法
    public void runLeftStop() {
        if (!status.contains("jump")) {
            status = Action.STAND_LEFT;
        } else {
            status = Action.JUMP_LEFT;
        }
        xSpeed = 0;
    }

    //马里奥向右移动停止的方法
    public void runRightStop() {
        if (!status.contains("jump")) {
            status = Action.STAND_RIGHT;
        } else {
            status = Action.JUMP_RIGHT;
        }
        xSpeed = 0;
    }


    public int getX() {
        return x;
    }

    public void setX(int x) {
        this.x = x;
    }

    public int getY() {
        return y;
    }

    public void setY(int y) {
        this.y = y;
    }

    public String getStatus() {
        return status;
    }

    public void setStatus(String status) {
        this.status = status;
    }

    public BufferedImage getMarioImage() {
        return marioImage;
    }

    public void setMarioImage(BufferedImage marioImage) {
        this.marioImage = marioImage;
    }

    public LevelMap getLevelMap() {
        return levelMap;
    }

    public void setLevelMap(LevelMap levelMap) {
        this.levelMap = levelMap;
    }

    public Thread getThread() {
        return thread;
    }

    public void setThread(Thread thread) {
        this.thread = thread;
    }

    public int getxSpeed() {
        return xSpeed;
    }

    public void setxSpeed(int xSpeed) {
        this.xSpeed = xSpeed;
    }

    public int getySpeed() {
        return ySpeed;
    }

    public void setySpeed(int ySpeed) {
        this.ySpeed = ySpeed;
    }

    public int getUp() {
        return up;
    }

    public void setUp(int up) {
        this.up = up;
    }

    @Override
    public void run() {
        int index = 0;
        //控制马里奥无限移动
        while (true) {
            //判断当前是否移动，xSpeed<0左移动，xSpeed>0右移动
            if (xSpeed < 0 || xSpeed > 0) {
                x += xSpeed;
                if (x < 0) {
                    x = 0;
                }
            }

            if (ySpeed < 0 || ySpeed > 0) {
                y += ySpeed;
                if (y > 420) {
                    y = 420;
                    jumpStop();
                }
                if (y < 280) {
                    y = 280;
                }
            }

            //判断移动状态，跑步状态图片切换
            if (status.contains("run")) {
                index = index == 0 ? 1 : 0;
            }
            //根据马里奥的状态切换不同的图片
            if (Action.RUN_LEFT.equals(status)) {
                marioImage = Constant.runL.get(index);
            }
            if (Action.RUN_RIGHT.equals(status)) {
                marioImage = Constant.runR.get(index);
            }
            if (Action.STAND_LEFT.equals(status)) {
                marioImage = Constant.standL;
            }
            if (Action.STAND_RIGHT.equals(status)) {
                marioImage = Constant.standR;
            }
            if (Action.JUMP_LEFT.equals(status)) {
                marioImage = Constant.jumpL;
            }
            if (Action.JUMP_RIGHT.equals(status)) {
                marioImage = Constant.jumpR;
            }

            // 控制线程的速度
            try {
                Thread.sleep(30);
            } catch (InterruptedException e) {
                throw new RuntimeException(e);
            }
        }
    }

}

8. 编写程序入口

创建游戏窗口，并对窗口的基本属性进行设置，创建三个关卡，并调用 repaint 方法绘制场景。

package com.zxe;

import com.zxe.beans.LevelMap;
import com.zxe.beans.Mario;
import com.zxe.utils.Constant;
import com.zxe.beans.MyFrame;

import javax.swing.*;

public class Main {
    public static void main(String[] args) {
        //创建窗口对象
        MyFrame myFrame = new MyFrame();
        //设置窗口大小
        myFrame.setSize(1045,500);
        //设置窗口居中
        myFrame.setLocationRelativeTo(null);
        //设置窗口可见性
        myFrame.setVisible(true);
        //设置窗口关闭程序
        myFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        //设置键盘监听事件
        myFrame.addKeyListener(myFrame);
        //设置窗口的大小不可改变
        myFrame.setResizable(false);
        //设置窗口标题
        myFrame.setTitle("超级玛丽");

        //加载图片
        Constant.initImage();
        //创建三个关卡地图
        for (int i = 1; i <= 3; i++) {
            myFrame.getLevelMaps().add(new LevelMap(i));
        }
        //设置当前关卡地图
        myFrame.setLevelMap(myFrame.getLevelMaps().get(0));

        //创建马里奥
        Mario mario = new Mario(50, 420);
        myFrame.setMario(mario);
        mario.setLevelMap(myFrame.getLevelMap());

        //绘制场景
        myFrame.repaint();

        Thread thread = new Thread(myFrame);
        thread.start();
    }
}