snake.java

java编写的贪吃蛇的源代码,myeclipse平台实现

package com.nilaiya.snake.entities;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.Set;

import com.nilaiya.snake.listener.SnakeListener;
import com.nilaiya.snake.util.Global;

/**
 * @author yellow
 *
 */
public class Snake {

	//判断蛇是否死掉
	boolean lift;

	//蛇的最后一个节点
	private Point oldTail;

	//表示方向的常量
	public static final int UP = -1;

	public static final int DOWN = 1;

	public static final int LEFT = 2;

	public static final int RIGHT = -2;

	//保存蛇的方向 
	private int oldDirection, newDirection;

	//保存蛇的所有坐标,用集合表示
	private LinkedList<Point> body = new LinkedList<Point>();

	//蛇的监听器,可以注册多个监听器
	private Set<SnakeListener> listeners = new HashSet<SnakeListener>();

	/**
	 * 构造器
	 *
	 */
	public Snake() {
		init();
	}

	/**
	 * 蛇死掉的方法
	 *
	 */
	public void die() {
		lift = false;
		System.out.println("蛇死掉了！");
	}

	/**
	 * 得到蛇头的坐标
	 * @return Point
	 * @return the body.getFirst()
	 */
	public Point getHead() {
		return body.getFirst();
	}

	/**
	 * 初始化蛇
	 *
	 */
	public void init() {
		int x = Global.WIDTH / 2;
		int y = Global.HEIGHT / 2;
		for (int i = 0; i < 3; i++) {
			body.addLast(new Point(x--, y));//蛇头在右边(最中间)
		}
		//蛇头默认移动方向向右
		oldDirection = newDirection = RIGHT;

		lift = true;//蛇一开始是活的
	}

	/**
	 * 添加监听器的方法
	 * @param l
	 */
	public void addSnakeListener(SnakeListener l) {
		if (l != null) {
			this.listeners.add(l);
		}
	}

	/**
	 * 蛇的移动方法
	 *
	 */
	public void move() {
		System.out.println("蛇移动了！");
		if (!(oldDirection + newDirection == 0)) {
			oldDirection = newDirection;
		}
		//1.去掉尾部
		oldTail = body.removeLast();

		//得到蛇头的坐标
		int x = body.getFirst().x;
		int y = body.getFirst().y;

		//根据方向计算蛇头的新坐标
		switch (oldDirection) {
		case UP:
			y--;
			if (y < 0) {
				y = Global.HEIGHT - 1;
			}
			break;
		case DOWN:
			y++;
			if (y >= Global.HEIGHT) {
				y = 0;
			}
			break;
		case LEFT:
			x--;
			if (x < 0) {
				x = Global.WIDTH - 1;
			}
			break;
		case RIGHT:
			x++;
			if (x >= Global.WIDTH) {
				x = 0;
			}
			break;
		}
		//新的蛇头坐标 
		Point newHead = new Point(x, y);
		//2.加头
		body.addFirst(newHead);
	}

	/**
	 * 蛇改变方向的方法
	 * @param direction
	 */
	public void changeDirection(int direction) {
		System.out.println("蛇改变方向了！");
		newDirection = direction;
	}

	/**
	 * 蛇吃食物的方法
	 *
	 */
	public void eatFood() {
		System.out.println("蛇吃食物了！");

		body.addLast(oldTail);
	}

	/**
	 * 判断蛇是否吃到了自己的身体
	 * @return boolean
	 */
	public boolean isEatBody() {
		System.out.println("蛇吃到自己的身体了！");

		for (int i = 1; i < body.size(); i++) {
			if (body.get(i).equals(this.getHead())) {
				return true;
			}
		}
		return false;
	}

	/**
	 * 显示蛇的方法
	 * @param g
	 */
	public void drawMe(Graphics g) {
		System.out.println("显示蛇的方法");
		g.setColor(Color.BLUE);
		//填充格子
		for (Point p : body) {
			g.fill3DRect(p.x * Global.CELL_SIZE, p.y * Global.CELL_SIZE,
					Global.CELL_SIZE, Global.CELL_SIZE, true);
		}

	}

	/**
	 * 内部类
	 * 蛇一开始要不停的移动
	 * @author yellow
	 *
	 */
	private class SnakeMove implements Runnable {

		public void run() {
			while (lift) {
				move();
				//循环所有的遍历
				for (SnakeListener l : listeners) {
					l.snakeMoved(Snake.this);
				}
				try {
					Thread.sleep(300);
				} catch (InterruptedException e) {
					e.printStackTrace();
					System.out.println("线程延迟出错！");
				}
			}
		}
	}

	/**
	 * 启动线程的方法
	 *
	 */
	public void start() {
		new Thread(new SnakeMove()).start();
	}
}