snakecanver.java

贪吃蛇游戏的J2ME实现

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package hello;


import java.util.*;
import javax.microedition.lcdui.*;

/**
 *
 * @author Administrator
 */
public class SnakeCanver extends Canvas implements Runnable {
    
      /**存储贪吃蛇节点坐标,其中第二维下标为0的代表x坐标，第二维下标是1的代表y坐标*/
    int[][] snake = new int[200][2];
    /**已经使用的节点数量*/
    int snakeNum;
    /**贪吃蛇运动方向,0代表向上，1代表向下,2代表向左,3代表向右*/
    int direction;
    /*移动方向*/
    /**向上*/
    private final int DIRECTION_UP = 0;
    /**向下*/
    private final int DIRECTION_DOWN = 1;
    /**向左*/
    private final int DIRECTION_LEFT = 2;
    /**向右*/
    private final int DIRECTION_RIGHT = 3;

    /**游戏区域宽度*/
    int width;
    /**游戏区域高度*/
    int height;

    /**蛇身单元宽度*/
    private final byte SNAKEWIDTH = 4;

    /**是否处于暂停状态,true代表暂停*/
    boolean isPause = false;
    /**是否处于运行状态,true代表运行*/
    boolean isRun = true;

    /**时间间隔*/
    private final int SLEEP_TIME = 300;
    
    /**食物的X坐标*/
    int foodX=100;
    /**食物的Y坐标*/
    int foodY=100;
    /**食物的闪烁控制*/
    boolean b = true;
    
    /**Random对象*/
    Random random = new Random();
    
    public   SnakeCanver()
    {
        init();
        snakeNum=7;      
        for(int i=0;i<snakeNum;i++)
        {
            snake[i][0]=100-(SNAKEWIDTH*i);
            snake[i][1]=40;
        }
        direction=DIRECTION_RIGHT;
        foodX=100;
        foodY=100;
        width=this.getWidth();
        height=this.getHeight();
        new Thread(this).start();
        
    }
    public void init()
    { 
    
        
    }
    
    public void paint(Graphics g)
    {
        g.setColor(0xffffff);
        g.fillRect(0,0,width,height);
        g.setColor(0);
        
               
        if(b)
            g.fillRect(foodX, foodY, SNAKEWIDTH, SNAKEWIDTH);
        
        for(int i=0;i<snakeNum;i++)
            g.fillRect(snake[i][0], snake[i][1], SNAKEWIDTH, SNAKEWIDTH);

    }
    
      
    public void move(int dir)
    {
        for(int i=snakeNum-1;i>0;i--)
        {
            snake[i][0]=snake[i-1][0];
            snake[i][1]=snake[i-1][1];
        }
        switch(dir){
            case DIRECTION_UP:
                snake[0][1]=snake[0][1]-SNAKEWIDTH;
                break;
            case DIRECTION_DOWN:
                snake[0][1]=snake[0][1]+SNAKEWIDTH;
                break;
            case DIRECTION_LEFT:
                snake[0][0]=snake[0][0]-SNAKEWIDTH;
                break;
            case DIRECTION_RIGHT:
                snake[0][0]=snake[0][0]+SNAKEWIDTH;
                break;              
        }
        
    }
    
    public void eatFoot()
    {
        if(snake[0][0]==foodX&&snake[0][1]==foodY)
        {
            snakeNum++;
            generate();
        }
        
    }
    
    public void generate()
    {
        while(true){
            foodX=Math.abs(random.nextInt()%(width-SNAKEWIDTH+1))/SNAKEWIDTH*SNAKEWIDTH;
            foodY=Math.abs(random.nextInt()%(height-SNAKEWIDTH+1))/SNAKEWIDTH*SNAKEWIDTH;
            int flag=0;
            for(int i=0;i<snakeNum;i++)
                if(snake[i][0]==foodX&&snake[i][1]==foodY)
                {
                    flag=1;
                    break;
                }
             
            if(flag==0)
                break;
        }
    }
    
  
  
    
    public boolean isover()
    {
        if(snake[0][0]<0||snake[0][0]>(width-SNAKEWIDTH))
            return true;
        if(snake[0][1]<0||snake[0][1]>(height-SNAKEWIDTH))
            return true;
        for(int i=4;i<snakeNum;i++)
            if(snake[0][0]==snake[i][0]&&snake[0][1]==snake[i][1])
                return true;
        
        return false;
    }
        

    public void keyPressed(int keyCode)
    {
        int key=this.getGameAction(keyCode);
        switch(key)
        {
            case UP:
                if(direction!=DIRECTION_DOWN)
                    direction=DIRECTION_UP;
                break;
            case DOWN:
                if(direction!=DIRECTION_UP)
                    direction=DIRECTION_DOWN;
                break;
            case LEFT:
                if(direction!=DIRECTION_RIGHT)
                    direction=DIRECTION_LEFT;
                break;
            case RIGHT:
                if(direction!=DIRECTION_LEFT)
                        direction=DIRECTION_RIGHT;
                break;
            case FIRE:
                isPause=!isPause;
                break;
                
        }
    }
    
    public void run()
    {
        try{
            while(isRun)
            {
                long start=System.currentTimeMillis();
                if(!isPause)
                {
                    eatFoot();
                    move(direction);
                    if(isover())
                    {
                        break;
                    }
                    b=!b;
                }
                repaint();
                long end=System.currentTimeMillis();
                if(end - start < SLEEP_TIME){
                 Thread.sleep(SLEEP_TIME - (end - start)); 
                }
            }
        }catch(Exception e)
        {
            
        }
        
    }

}