java贪吃蛇demo

import javax.swing.*;
import java.awt.*;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.geom.Line2D;
import java.util.*;

/**
 *  Version:1.5
 *  功能：画出10*10个方格
 *  0  1  2  3 4 5 6 7 8 9
 *  10 11
 *  ......................
 *  ....................99
 *  在任意位置显示一个方格，并让键盘控制运动方向,连续运动
 *  产生随机苹果，可以判断是否吃掉。
 *  改动：用可变长数组来存放蛇身。
 *  完成基本效果
 */
public class SnakeDemo5 {
    private  JFrame frame;
    private int AppleDisplayFlag = 1; // 苹果是否显示标志位
    private int UPFlag = 0;int DownFlag=0;int LeftFlag=0;int RightFlag=0;
    private int SnakeHead = 2;
    private int AppleIndex = 0;
    private int numberOfRow = 20;  // 改变每行的box数量
    private int numberOfBox = numberOfRow * numberOfRow;
    private int[] BoxDisplayFlag = new int[numberOfBox];// 刷新时遍历，根据flag选择是否显示对应的box
    private Vector snakeBody = new Vector();
    int snakeEndBuf = 0;

    public static void main(String[] args) {
        SnakeDemo5 snake = new SnakeDemo5();
        snake.go();
    }
    private void go(){
        frame = new JFrame();
        MyDrawPanel myDrawPanel = new MyDrawPanel();
        frame.addKeyListener(myDrawPanel);

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(myDrawPanel);  // 把自己的画板加到frame框架中
        frame.setSize(300, 300);  // 框架窗口大小
        frame.setVisible(true);  // 最后把frame显示出来
        snakeBody.add(SnakeHead);
        snakeBody.add(1);
        snakeBody.add(0);
        for(int i=0; i<snakeBody.size();i++){  // 初始化，画板2号格子蛇头，snakeBody的0号元素。
            BoxDisplayFlag[(int) snakeBody.get(i)] = 1;
        }

        AppleIndex = (int) (Math.random()*100);
        while(true){
            if(DownFlag == 1){
                snakeEndBuf = (int) snakeBody.get(snakeBody.size()-1);
                for(int i=snakeBody.size()-1; i>0; i--){  // 更新蛇身，前一个(显示位置)赋给后一个
                    snakeBody.set(i, snakeBody.get(i-1));
                }
                SnakeHead += numberOfRow;
                snakeBody.set(0, SnakeHead);    // 蛇头单独算
                if(AppleIndex == SnakeHead){    // 吃了苹果
                    AppleIndex = (int) (Math.random()*100);
                    snakeBody.add(snakeEndBuf); // 把苹果加到蛇身尾部，蛇长+1(原尾部的蛇身已经前一个覆盖掉)
                }
                for(int i=0; i<BoxDisplayFlag.length; i++){BoxDisplayFlag[i]=0;} // 清零
                for(int i=0; i<snakeBody.size(); i++){
                    BoxDisplayFlag[(int) snakeBody.get(i)]=1;
                }
                frame.repaint();    // 刷新
            }
            if(UPFlag == 1){
                snakeEndBuf = (int) snakeBody.get(snakeBody.size()-1);
                for(int i=snakeBody.size()-1; i>0; i--){
                    snakeBody.set(i, snakeBody.get(i-1));
                }
                SnakeHead -= numberOfRow;
                snakeBody.set(0, SnakeHead);
                if(AppleIndex == SnakeHead){  // 吃了苹果
                    AppleIndex = (int) (Math.random()*100);
                    snakeBody.add(snakeEndBuf);
                }
                for(int i=0; i<BoxDisplayFlag.length; i++){BoxDisplayFlag[i]=0;} // 清零
                for(int i=0; i<snakeBody.size(); i++){
                    BoxDisplayFlag[(int) snakeBody.get(i)]=1;
                }
                frame.repaint();    // 刷新
            }
            if(LeftFlag == 1){
                snakeEndBuf = (int) snakeBody.get(snakeBody.size()-1);
                for(int i=snakeBody.size()-1; i>0; i--){
                    snakeBody.set(i, snakeBody.get(i-1));
                }
                SnakeHead -= 1;
                snakeBody.set(0, SnakeHead);
                if(AppleIndex == SnakeHead){  // 吃了苹果
                    AppleIndex = (int) (Math.random()*100);
                    snakeBody.add(snakeEndBuf);
                }
                for(int i=0; i<BoxDisplayFlag.length; i++){BoxDisplayFlag[i]=0;} // 清零
                for(int i=0; i<snakeBody.size(); i++){
                    BoxDisplayFlag[(int) snakeBody.get(i)]=1;
                }
                frame.repaint();    // 刷新
            }
            if(RightFlag == 1){
                snakeEndBuf = (int) snakeBody.get(snakeBody.size()-1);
                for(int i=snakeBody.size()-1; i>0; i--){
                    snakeBody.set(i, snakeBody.get(i-1));
                }
                SnakeHead += 1;
                snakeBody.set(0, SnakeHead);
                if(AppleIndex == SnakeHead){  // 吃了苹果
                    AppleIndex = (int) (Math.random()*100);
                    snakeBody.add(snakeEndBuf);
                }
                for(int i=0; i<BoxDisplayFlag.length; i++){BoxDisplayFlag[i]=0;} // 清零
                for(int i=0; i<snakeBody.size(); i++){
                    BoxDisplayFlag[(int) snakeBody.get(i)]=1;
                }
                frame.repaint();    // 刷新
            }

            try{
                Thread.sleep(100); // 控制运行速度
            }catch (Exception ex){};
        }
    }
    /* 自己的画板panel */
    class MyDrawPanel extends JPanel implements KeyListener {
        double width = 0, height = 0;

        public void paintComponent(Graphics g) {
            Graphics2D g2 = (Graphics2D) g;
            double leftX = 0, topY = 0;
            for(int i=0; i<numberOfRow; i++){
                width = (double) getWidth()/numberOfRow;
                height = (double) getHeight()/numberOfRow;
                g2.draw(new Line2D.Double(leftX+i*width, topY, leftX+i*width,numberOfRow*height));// 竖
                g2.draw(new Line2D.Double(leftX, topY+i*height,numberOfRow*width, topY+i*height));// 行
            }
            /* numberOfBox个Box，编号0-numberOfBox 查询需要显示的方格*/
            for(int i=0; i<numberOfBox; i++){
                if(BoxDisplayFlag[i] == 1){
                    width = (double) getWidth()/numberOfRow;
                    height = (double) getHeight()/numberOfRow;
                    topY =(double)(i / (numberOfRow)) * (double) getHeight() / numberOfRow;
                    leftX =(double)(i % (numberOfRow)) * (double) getWidth() / numberOfRow;
                    g2.fillRect((int)leftX,(int)topY,(int)width,(int)height);
                }
            }
            if(AppleDisplayFlag == 1){ // 苹果可以显示
                double topY_apple=0, leftX_apple=0;
                width = (double) getWidth()/numberOfRow;
                height = (double) getHeight()/numberOfRow;
                topY_apple =(double)(AppleIndex / (numberOfRow)) * (double) getHeight() / numberOfRow;
                leftX_apple =(double)(AppleIndex % (numberOfRow)) * (double) getWidth() / numberOfRow;
                g2.fillRect((int)leftX_apple,(int)topY_apple,(int)width,(int)height);
                System.out.println(AppleIndex);
            }
        }

        @Override
        public void keyTyped(KeyEvent e) {
        }

        @Override
        public void keyPressed(KeyEvent e) {
//            System.out.println("被按下"+ (char)e.getKeyCode()); // 测试
            switch(e.getKeyCode())
            {
                case KeyEvent.VK_UP:
                    UPFlag =1;
                    DownFlag = 0;
                    LeftFlag = 0;
                    RightFlag = 0;
                    break;
                case KeyEvent.VK_DOWN:
                    UPFlag =0;
                    DownFlag = 1;
                    LeftFlag = 0;
                    RightFlag = 0;
                    break;
                case KeyEvent.VK_LEFT:
                    UPFlag =0;
                    DownFlag = 0;
                    LeftFlag = 1;
                    RightFlag = 0;
                    break;
                case KeyEvent.VK_RIGHT:
                    UPFlag =0;
                    DownFlag = 0;
                    LeftFlag = 0;
                    RightFlag = 1;
                    break;
            }
        }
        @Override
        public void keyReleased(KeyEvent e) {
        }
    }
}