Java_Day14

Java learning_Day14

本人学习视频用的是马士兵的，也在这里献上
<链接：https://pan.baidu.com/s/1qKNGJNh0GgvlJnitTJGqgA>
提取码：fobs

主要内容：

小游戏：贪吃蛇

成果图：

代码

Yard.java 部分

摘要：下面程序段主要用于显示背景界面以及游戏的开始与结束。

import java.awt.*;
import java.awt.event.*;

public class Yard extends Frame {
    PaintThread paintThread = new PaintThread();
    
    private boolean flag = true;  //判断游戏是否结束
    
    //游戏的行列和每个格子的大小
    public static final int ROWS = 30;
    public static final int COLS = 30;
    public static final int BLOCK_SIZE = 15;
    
    private int score = 0;
    
    Snake s = new Snake(this);
    Egg e = new Egg();
    
    Image offScreenImage = null;
    
    //初始化游戏界面
    public void launch() {
        this.setLocation(200, 200);
        this.setSize(COLS * BLOCK_SIZE, ROWS * BLOCK_SIZE);
        this.addWindowListener(new WindowAdapter() {

            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
            
        });
        this.setVisible(true);
        this.addKeyListener(new KeyMonitor());;
        
        new Thread(paintThread).start();
    }
    
    public static void main(String[] args) {
        new Yard().launch();
    }
    
    //当游戏终止操作
    public void stop() {
        flag = false;
    }

    //画出背景，游戏动画的执行部分
    @Override
    public void paint(Graphics g) {
        Color c = g.getColor();
        g.setColor(Color.GRAY);
        g.fillRect(0, 0, COLS * BLOCK_SIZE, ROWS * BLOCK_SIZE);
        g.setColor(Color.DARK_GRAY);
        //画出横线
        for (int i = 1; i < ROWS; i++) {
            g.drawLine(0, BLOCK_SIZE * i, COLS * BLOCK_SIZE, BLOCK_SIZE * i);
        }
        //画出竖线
        for (int i = 1; i < COLS; i++) {
            g.drawLine(BLOCK_SIZE * i, 0, BLOCK_SIZE * i, ROWS * BLOCK_SIZE);
        }
        
        g.setColor(Color.YELLOW);
        g.drawString("score" + score, 10, 60);
        
        
        s.eat(e);
        e.draw(g);
        s.draw(g);
        
        //当游戏结束时，提示玩家
        if(flag == false) {
            g.setFont(new Font("华文彩云", Font.BOLD | Font.HANGING_BASELINE, 50));
            g.drawString("game over", 105, 240);
            paintThread.pause();
        }
        g.setColor(c);
    }
    
    //防止画面闪烁
    @Override
    public void update(Graphics g) {
        if(offScreenImage == null) {
            offScreenImage = this.createImage(COLS * BLOCK_SIZE, ROWS * BLOCK_SIZE);
        }
        Graphics gOff = offScreenImage.getGraphics();
        paint(gOff);
        g.drawImage(offScreenImage, 0, 0, null);
    }

    //控制动作的进行和终止
    private class PaintThread implements Runnable {
        private boolean pause = false;
        
        public void run() {
            while(flag) {
                if(pause) continue;
                else repaint();
                
                try {
                    Thread.sleep(100);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
        
        public void pause() {
            this.pause = true;
        }
        
        public void reStart() {
            pause = false;
            s = new Snake(Yard.this);
        }
    }
    
    private class KeyMonitor extends KeyAdapter {

        @Override
        public void keyPressed(KeyEvent e) {
            int key = e.getKeyCode();
            if(key == KeyEvent.VK_F2) paintThread.reStart();  //当按下F2时重玩游戏
            s.keyPressed(e);
        }
        
    }

    public int getScore() {
        return score;
    }

    public void setScore(int score) {
        this.score = score;
        
    }
    
}

Snake.java

摘要：下面程序段主要用于响应蛇的相关操作。

import java.awt.*;
import java.awt.event.KeyEvent;

public class Snake {
    private Node head = null;
    private Node tail = null;
    private int size = 0;
    
    private Node n = new Node(20, 30, Dir.L);
    private Yard y;
    
    public  Snake(Node node) {
        head = node;
        tail = node;
        size = 1;
    }
    
    public Snake(Yard y) {
        head = n;
        tail = n;
        size = 1;
        this.y = y;
    }
    
    //将节点加在蛇的尾巴上
    public void addToTail() {
        Node node = null;
        switch(tail.dir) {
        case L :
            node = new Node(tail.row, tail.col + 1, tail.dir);
            break;
        case U :
            node = new Node(tail.row + 1, tail.col, tail.dir);
            break;
        case R :
            node = new Node(tail.row, tail.col - 1, tail.dir);
            break;
        case D :
            node = new Node(tail.row - 1, tail.col, tail.dir);
            break;
        }
        tail.next = node;
        node.prev = tail;
        tail = node;
        size++;
    }
    
    //将节点加在蛇的头部
    public void addToHead() {
        Node node = null;
        switch(head.dir) {
        case L :
            node = new Node(head.row, head.col - 1, head.dir);
            break;
        case U :
            node = new Node(head.row - 1, head.col, head.dir);
            break;
        case R :
            node = new Node(head.row, head.col + 1, head.dir);
            break;
        case D :
            node = new Node(head.row + 1, head.col, head.dir);
            break;
        }
        node.next = head;
        head.prev = node;
        head = node;
        size++;
    }
    
    //画蛇
    public void draw(Graphics g) {
        if (size <= 0) return;
        move();
        for (Node n = head; n != null; n = n.next) {
            n.draw(g);
        }
    }
    
    //控制蛇的移动
    private void move() {
        addToHead();
        deleteFromTail();
        checkDead();
    }

    //检验蛇是否死亡
    private void checkDead() {
        if(head.row < 2 || head.col < 0 || head.row > Yard.ROWS || head.col > Yard.COLS) {
            y.stop();
        }
        
        for(Node n = head.next; n != null; n = n.next) {
            if(head.row == n.row & head.col == n.col) y.stop();
        }
        
    }

    //将蛇的尾部去除，主要用于蛇的移动
    private void deleteFromTail() {
        if(size == 0) return;
        tail = tail.prev;
        tail.next = null;
        
    }

    //蛇的每一个节点的属性
    private class Node {
        int w = Yard.BLOCK_SIZE;
        int h = Yard.BLOCK_SIZE;
        int row, col;
        Dir dir = Dir.L;
        Node next = null;
        Node prev = null; 
        
        Node(int row, int col, Dir dir) {
            this.row = row;
            this.col = col;
            this.dir = dir;
        }
        
        //蛇的身体的绘画
        void draw(Graphics g) {
            Color c = g.getColor();
            g.setColor(Color.BLACK);
            g.fillRect(Yard.BLOCK_SIZE * col, Yard.BLOCK_SIZE * row, w, h);
            g.setColor(c);
        }
    }

    //蛇吃了蛋的响应
    public void eat(Egg e) {
        if(this.getRect().intersects(e.getRect())) {
            e.reAppear();
            this.addToHead();
            y.setScore(y.getScore() + 5);
        }
    }
    
    //返回蛇头的位置
    private Rectangle getRect() {
        return new Rectangle(Yard.BLOCK_SIZE * head.col, Yard.BLOCK_SIZE * head.row, head.w, head.h);
    }
    
    //响应玩家按键
    public void keyPressed(KeyEvent e) {
        int key = e.getKeyCode();
        switch(key) {
        case KeyEvent.VK_LEFT :
            if(head.dir != Dir.R) head.dir = Dir.L;
            break;
        case KeyEvent.VK_UP :
            if(head.dir != Dir.D) head.dir = Dir.U;
            break;
        case KeyEvent.VK_RIGHT :
            if(head.dir != Dir.L) head.dir = Dir.R;
            break;
        case KeyEvent.VK_DOWN :
            if(head.dir != Dir.U) head.dir = Dir.D;
            break;
        }
    }
}

Egg.java 部分

摘要：下面程序段主要用于生成蛋。

import java.awt.*;
import java.util.Random;

public class Egg {

    int row, col;
    int w = Yard.BLOCK_SIZE;
    int h = Yard.BLOCK_SIZE;
    private static Random r = new Random();
    private Color color = Color.GREEN;

    public Egg(int row, int col) {
        this.row = row;
        this.col = col;
    }
    
    public Egg() {
        this(r.nextInt(Yard.ROWS-2) + 2, r.nextInt(Yard.COLS));
    }
    
    //使蛋随机出现
    public void reAppear() {
        this.row = r.nextInt(Yard.ROWS-2) + 2;
        this.col = r.nextInt(Yard.COLS);
    }
    
    //返回蛋的位置
    public Rectangle getRect() {
        return new Rectangle(Yard.BLOCK_SIZE * this.col, Yard.BLOCK_SIZE * this.row, this.w, this.h);
    }
    
    //画蛋
    public void draw(Graphics g) {
        Color c = g.getColor();
        g.setColor(color);
        g.fillOval(Yard.BLOCK_SIZE * col, Yard.BLOCK_SIZE * row, w, h);
        g.setColor(c);
        if(color == Color.GREEN) color = Color.RED;
        else color = Color.GREEN;
    }
    
    public int getRow() {
        return row;
    }

    public void setRow(int row) {
        this.row = row;
    }

    public int getCol() {
        return col;
    }

    public void setCol(int col) {
        this.col = col;
    }
}

Dir.java 部分

摘要：四个方向键。

public enum Dir {
    L, U, R, D
}