greedsnake.java

这是一个java贪吃蛇小游戏

//文件名：GreedSnake.java

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.*;

public class GreedSnake implements KeyListener
{
JFrame mainFrame;
Canvas paintCanvas;
JLabel labelScore;//计分牌
SnakeModel snakeModel=null;// 蛇
public static final int canvasWidth=900;
public static final int canvasHeight=600;
public static final int nodeWidth=30;
public static final int nodeHeight=20;

//GreedSnake():初始化游戏界面

public GreedSnake()
{
//设置界面元素
mainFrame=new JFrame("贪食蛇小游戏！");
Container cp=mainFrame.getContentPane();
labelScore=new JLabel("Score:");
cp.add(labelScore,BorderLayout.NORTH);
paintCanvas=new Canvas();
paintCanvas.setSize(canvasWidth+1,canvasHeight+1);
paintCanvas.addKeyListener(this);
cp.add(paintCanvas,BorderLayout.CENTER);
JPanel panelButtom=new JPanel();
panelButtom.setLayout(new BorderLayout());
JLabel labelHelp;// 帮助信息
labelHelp=new JLabel("PageUp加速, PageDown减速;",JLabel.CENTER);
panelButtom.add(labelHelp,BorderLayout.NORTH);
labelHelp=new JLabel("回车键重玩",JLabel.CENTER);
panelButtom.add(labelHelp,BorderLayout.CENTER);
labelHelp=new JLabel("空格暂停或开始",JLabel.CENTER);
panelButtom.add(labelHelp,BorderLayout.SOUTH);
cp.add(panelButtom,BorderLayout.SOUTH);
mainFrame.addKeyListener(this);
mainFrame.pack();
mainFrame.setResizable(false);
mainFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
mainFrame.setVisible(true);
begin();
}

//keyPressed():按键检测

public void keyPressed(KeyEvent e)
{
int keyCode=e.getKeyCode();
if(snakeModel.running) switch(keyCode)
{
case KeyEvent.VK_UP:
snakeModel.changeDirection(SnakeModel.UP);
break;
case KeyEvent.VK_DOWN:
snakeModel.changeDirection(SnakeModel.DOWN);
break;
case KeyEvent.VK_LEFT:
snakeModel.changeDirection(SnakeModel.LEFT);
break;
case KeyEvent.VK_RIGHT:
snakeModel.changeDirection(SnakeModel.RIGHT);
break;
case KeyEvent.VK_ADD:
case KeyEvent.VK_PAGE_UP:
snakeModel.speedUp();// 加速
break;
case KeyEvent.VK_SUBTRACT:
case KeyEvent.VK_PAGE_DOWN:
snakeModel.speedDown();// 减速
break;
case KeyEvent.VK_SPACE:
case KeyEvent.VK_P:
snakeModel.changePauseState();// 暂停或继续
break;
default:
}
//重新开始
if(keyCode==KeyEvent.VK_R || keyCode==KeyEvent.VK_S
|| keyCode==KeyEvent.VK_ENTER)
{
snakeModel.running=false;
begin();
}
}

//keyReleased（）：空函数

public void keyReleased(KeyEvent e)
{
}

//keyTyped（）：空函数

public void keyTyped(KeyEvent e)
{
}

//repaint（）：绘制游戏界面（包括蛇和食物）

void repaint()
{
Graphics g=paintCanvas.getGraphics();
//draw background
g.setColor(Color.BLUE);
g.fillRect(0,0,canvasWidth,canvasHeight);
//draw the snake
g.setColor(Color.RED);
LinkedList na=snakeModel.nodeArray;
Iterator it=na.iterator();
while(it.hasNext())
{
Node n=(Node)it.next();
drawNode(g,n);
}
// draw the food
g.setColor(Color.RED);
Node n=snakeModel.food;
drawNode(g,n);
updateScore();
}

//drawNode（）：绘画某一结点（蛇身或食物）

private void drawNode(Graphics g,Node n)
{
g.fillRect(n.x*nodeWidth,n.y*nodeHeight,nodeWidth-1,nodeHeight-1);
}

//updateScore（）：改变计分牌

public void updateScore()
{
String s="Score: "+snakeModel.score;
labelScore.setText(s);
}

//begin（）：游戏开始，放置贪吃蛇

void begin()
{
if(snakeModel==null||!snakeModel.running)
{
snakeModel=new SnakeModel(this,canvasWidth/nodeWidth,
this.canvasHeight/nodeHeight);
(new Thread(snakeModel)).start();
}
}

//main（）：主函数

public static void main(String[] args)
{
GreedSnake gs=new GreedSnake();
}
}