party.java

Java编程技巧

import java.applet.*;
import java.awt.*;
import java.net.*;

//定义抽象类Thing
abstract class Thing
{
    Party parent;
    int x;
    int y;
    int new_x;
    int new_y;
    Image film;
    int frame = 0;
    
    abstract void paint (Graphics g);
	
   
    public void move (int x, int y)
    {
	new_x = x;
	new_y = y;
    }

    public void move (int x)
    {
	new_x = x;
    }

    public int getX ()
    {
	return x;
    }

    public int getY ()
    {
	return y;
    }
}


//定义类Flag为Thing的子类
class Flag extends Thing
{	Flag (Image film, Party parent)
	{this.film=film;}
	
	void paint(Graphics g)
	{	
		g.drawImage (film,20,0,100,90,parent);}

}


//定义类Letter为Thing的子类
class Letter extends Thing
{
    Letter (Image film, int frame, int x, int y, Party parent)
    {
	this.film = film;
	this.frame = frame;
	this.x = x;
	this.y = y;
	new_x = x;
	new_y = y;
    }

    public void paint (Graphics g)
    {
	if (new_x != x || new_y != y)
	{
	    
	    x = new_x;
	    y = new_y;
	}

	Graphics gc = g.create (x, y, 64, 64);
	gc.drawImage (film, 0, -(frame * 64), parent);
	gc.dispose ();
    }
   }

//定义类Snake为Thing的子类
class Snake extends Thing
{	Snake (Image film, int x, int y, Party parent)
	{
	this.film=film;
	this.x = x;
	this.y = y;
	this.parent = parent;
	new_x=x-20;
	
	}
	
	public void paint (Graphics g)
	{	
		if (new_x < x)
		{	
			
			if (x < 660)
			{	
			y=25;
			new_x=x;
			x+=20;
			Graphics gc=g.create (x, y, 70, 76);
			gc.drawImage (film, 0, 0, 70, 76, 70, 0, 0, 76, parent);
			gc.dispose();
			
			}
			else {new_x+=60;}
			
		}
		
		else 
		{
			if(x > -64)
			{
			y=270;
			new_x=x;
			x-=20;
			Graphics gc=g.create (x, y, 70, 76);
			gc.drawImage (film, 0, 0, 70, 76,parent);
			gc.dispose();
			
			}
			else new_x-=60;

		}
	}
}

//定义类Duke为Thing的子类
class Duke extends Thing
{
    boolean walking = true;
    
    Duke (Image film, int x, int y, Party parent)
    {
	this.film = film;
	this.x = x;
	this.y = y;
	this.parent = parent;
	new_x = x;
	new_y = y;
    }

    public void walk (int there, int step)
    {
	walking = true;
	
	if (there > x)
	{
	    while (x <= there)
	    {
		new_x += step;
		parent.repaint ();
		parent.sleep (100);
	    }
	}
	else
	{
	    while (x >= there)
	    {
		new_x -= step;
		parent.repaint ();
		parent.sleep (100);
	    }
	}
    }

    public void walk ()
    {
	walking = true;
    }

    public void wave (int nwaves)
    {
	walking = false;
	
	for (int i = 0; i < nwaves; i++)
	{
	    parent.repaint ();
	    parent.sleep (100);
	}
    }
    
    public void wave ()
    {
	walking = false;
    }
    
    public void paint (Graphics g)
    {
	x = new_x;
	y = new_y;

	Graphics gc = g.create (x, y, 55, 64);
	gc.drawImage (film, 0, -((walking ? frame : 2+frame) * 64), parent);
	gc.dispose ();
	
	frame++;
	if (frame == 2)
	{
	    frame = 0;
	}
    }
}

//定义类Party为Applet的子类
public class Party extends Applet implements Runnable
{
    //定义Letter的初始位置，移动速度，最终位置及次序
	int start[] = { -64, -64, -64, -64, 640, 640, 640, 640 };
    int increment[] = { 8, 8, 8, 8, -8, -8, -8, -8 };
    int end[] = { 64, 128, 192, 256, 320, 384, 448, 512 };
    int order[] = { 3, 4, 2, 5, 1, 6, 0, 7};
    
	char bannerChars[]={'1','9','2','1','.','7','~','2','0','0','1','.','7'};

    Image letterFilm;
    Letter letters[];
    int currentLetter = 0;

    Image dukeFilm;
    Duke duke;
    
	Image flagfilm;
	Flag flag;

	Image snakefilm;
	Snake snake;

	Image partyFilm;
	double sita;
	int dx1,dx2,width;

	Image backFilm;

	AudioClip soundClip;

	Button button1,button2;

	Thread thread = null;
    MediaTracker tracker = null;
    Image doubleBuffer;
    boolean paused = false;

    public void init ()
    {
	String param;
	int i;
	
	//控制音乐播放的按钮
	button1=new Button ("Play Music");
	add (button1); 
	button2=new Button ("Stop Music");
	add (button2);

	URL codeBase=getDocumentBase();
	soundClip=getAudioClip (codeBase,"Sound.au");
	
	//初始化Flag
	flagfilm=getImage (getDocumentBase (), "flag.gif");
	flag=new Flag (flagfilm,this);
		
	tracker = new MediaTracker (this);

	//初始化Duke
	dukeFilm = getImage (getDocumentBase (), "duke.gif");
	tracker.addImage (dukeFilm, 0);
	duke = new Duke (dukeFilm, -64, 160, this);

	//初始化Letters
	try
	{
	    param = getParameter ("LETTERS");
	    
	}
	catch (Exception e)
	{
	    return;
	}
	letterFilm = getImage (getDocumentBase (), param);
	tracker.addImage (letterFilm, 1);
	letters = new Letter[8];
	for (i = 0; i < 8; i++)
	{
	    letters[i] = new Letter (letterFilm, i, start[i], 160, this);
	}

	//初始化Snake
	snakefilm=getImage (getDocumentBase (), "snake.gif");
	tracker.addImage (snakefilm,4);
	snake=new Snake (snakefilm, -64, 0, this);

	//初始化背景
	backFilm=getImage (getDocumentBase (), "back.gif");
	tracker.addImage (backFilm, 3);

	
	partyFilm=getImage (getDocumentBase(), "partyr.gif");
	tracker.addImage (partyFilm,2);
	tracker.checkID(2);

	//使用双倍缓存
	doubleBuffer = createImage (640, 400);
	resize (640, 400);
	
	//开始线程
	thread = new Thread (this);
	thread.start ();
    }

    //处理按钮事件
	public boolean action (Event evt, Object arg)
	{
		if (evt.target instanceof Button)
			HandleButtons (arg);
		return true;
	}
	
	protected void HandleButtons( Object label)
	{
		if (label=="Play Music")
			soundClip.play();
		else if (label=="Stop Music")
			soundClip.stop();
	}


	public void sleep (long ms)
    {
	try
	{
	    Thread.sleep (ms);
	}
	catch (Exception e)
	{
	}
    }

    public void run ()
    {
	int i;
	
	//Thread.currentThread().setPriority (Thread.MIN_PRIORITY);


	tracker.checkID (0);
	tracker.checkID (1);
		
	
	//等待背景下载
	try
	{
	    tracker.waitForID (3);
	}
	catch (Exception e)
	{
	    return;
	}

	//等待Duke下载
	try
	{
	    tracker.waitForID (0);
	}
	catch (Exception e)
	{
	    return;
	}


	
	//等待Snake下载
	try
	{
	    tracker.waitForID (4);
	}
	catch (Exception e)
	{
	    return;
	}


	//确定Letters的开始位置
	for (i = 0; i < 8; i++)
	{
	    letters[i].move (start[i]);
	}

	//确定Duke的开始位置
	duke.move (-64);
	//让Duke走到中间
	duke.walk (295, 40);
	//Duke摇手
	duke.wave (13);
	//Duke走回去
	duke.walk (-64, 40);

	//Duke推字
	for (i = 0; i < 8; )
	{
	    repaint ();
	    sleep (100);

	    currentLetter = order[i];

	    //看看Letters是否已经就位
	    if ((increment[currentLetter] < 0 && letters[currentLetter].getX () <= end[currentLetter])
		|| (increment[currentLetter] > 0 && letters[currentLetter].getX () >= end[currentLetter]))
	    {
		if (i == 7)
		{
		    duke.walk (295, 40);
		    duke.wave (25);
		    duke.walk (40, 40);
		    duke.wave (5);
		    duke.walk (-64, 40);
		}
		else if (increment[currentLetter] > 0)
		{
		    duke.walk (640, 40);
		}
		else
		{
		    duke.walk (-64, 40);
		}
		
		i++; //下一个字
	    }
	    else
	    {
		//移动字
		letters[currentLetter].move (letters[currentLetter].getX () + increment[currentLetter]);

		//移动Duke
		if (increment[currentLetter] < 0)
		{
		    duke.move (letters[currentLetter].getX () + 40);
		}
		else
		{
		    duke.move (letters[currentLetter].getX () - 40);
		}
	    }
	}
	
	
	
	//字旋转一周
	for( sita=2; sita<90; )
	{
		dx1=(int)(64+(256-256*Math.cos(sita*Math.PI/180)));
		width=(int)(2*256*Math.cos(sita*Math.PI/180));
		repaint();
		sleep(80);
		sita+=2;

    }

	for(sita=90; sita<270; )
	{
		dx1=(int)(64+(256+256*Math.cos(sita*Math.PI/180)));
		dx2=(int)(64+(256-256*Math.cos(sita*Math.PI/180)));
		repaint();
		sleep(80);
		sita+=2;
	}

	for (sita=270; sita<=360; )
	{
		dx1=(int)(64+(256-256*Math.cos(sita*Math.PI/180)));
		width=(int)(2*256*Math.cos(sita*Math.PI/180));
		repaint();
		sleep(80);
		sita+=2;

    }
}
	//线程的开始方法
    public void start ()
    {
	if (thread == null)
	{
	    thread = new Thread (this);
	    thread.start ();
	}
    }

    //线程的停止方法
    public void stop ()
    {
	if (thread != null && thread.isAlive ())
	{
	    thread.stop ();
	    thread = null;
	}
    }

    //处理鼠标事件
    public boolean mouseDown (Event e, int x, int y)
    {
	if (thread != null)
	{
	    thread.stop ();
	    thread = null;
	}
	else
	{
	    thread = new Thread (this);
	    thread.start ();
		sita=0;
	}

	return true;
    }
    
    //处理键盘事件
    public boolean keyDown (Event e, int key)
    {
	switch (key)
	{
	case ' ':
	    if (thread != null)
	    {
		if (paused)
		{
		    thread.resume ();
		    paused = false;
		}
		else
		{
		    thread.suspend ();
		    paused = true;
		}
	    }
	    break;
	}
	    
	return true;
    }

    //重写Update方法
    public void update (Graphics g)
    {
	paint (g);
    }

    //在屏幕上显示图像
    public void paint (Graphics g)
    {
	Graphics db = doubleBuffer.getGraphics ();
	int i;
	
	//在后台上显示背景
	if (tracker.checkID (3, true))
	
		db.drawImage (backFilm, 0, 0, 640, 400, this);
	
	//在后台上显示字
	if (tracker.checkID (1, true) && (letters[7].getX()!=512 || duke.getX()>-80))
	{
	    for (i = 0; i < 8; i++)
	    {
		letters[i].paint (db);
	    }
	}
	
	//在后台上显示跳动的数字 
	for(int j=0; j<13; j++) 
	 {
			
            int x = (int) (10*Math.random() + 15*j);
            int y = (int) (10*Math.random() + 36);
            db.drawChars(bannerChars, j, 1, x+205, y+240);
	 }

	flag.paint (db);
	duke.paint (db);
	
	snake.paint (db);
	
	//显示字的旋转
	if (tracker.checkID (2, true))
	{
		
		if(sita>0 && sita<90)
		{	
			
			db.drawImage(partyFilm,dx1, 160, width, 64,this);
			
		}
		if (sita>=90 && sita<270)
		{
			
			db.drawImage(partyFilm,dx1,160,dx2,224,510,0,0,64,this);
			
		}
		if (sita>=270)
			
			db.drawImage(partyFilm,dx1, 160, width, 64,this);

	}
	

	//将后台上的图像显示到屏幕上
	g.drawImage (doubleBuffer, 0, 0, this);
	db.dispose ();
    
}
}