greedsnake.java

贪吃蛇的JAVA实现.实现了简单的贪吃蛇游戏

/**************************************************************************
 *文件名：GreedSnake.java
 *作者：C.Jason
 *要点分析：
 *1）主要部分已经集成为一个对象SnakeModel，利用键盘控制实现操作。
 *************************************************************************/
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.*;

// ＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
// Main Class
// ＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
public class GreedSnake implements KeyListener {
	JFrame mainFrame;
	Canvas paintCanvas;
	JLabel labelScore;// 计分牌
	SnakeModel snakeModel = null;// 蛇
	public static final int canvasWidth = 200;
	public static final int canvasHeight = 300;
	public static final int nodeWidth = 10;
	public static final int nodeHeight = 10;

	// ----------------------------------------------------------------------
	// GreedSnake():初始化游戏界面
	// ----------------------------------------------------------------------
	public GreedSnake()
{
// 设置界面元素
mainFrame=new JFrame("GreedSnake'");
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, PageDown for speed;",JLabel.CENTER);
panelButtom.add(labelHelp,BorderLayout.NORTH);
labelHelp=new JLabel("ENTER or R or S for start;",JLabel.CENTER);
panelButtom.add(labelHelp,BorderLayout.CENTER);
labelHelp=new JLabel("SPACE or P for pause",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.WHITE);
		g.fillRect(0, 0, canvasWidth, canvasHeight);
		// draw the snake
		g.setColor(Color.BLACK);
		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();
	}
}