countdown.java

Java 范例实战 光盘使用说明 ========================== 本光盘的文件结构如下所示： =====================================

import java.applet.Applet;
import java.applet.AppletContext;
import java.awt.*;
import java.io.PrintStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Date;

public class countdown extends Applet implements Runnable
{

    URL dest ;
    String saying, font ;
    Thread timer ;
    MediaTracker tracker ;
    int lastsec, totalSec, t_hours, t_mins, t_secs, t_month, t_day, 
    	t_year, t_daylight, tz_offset, rDays, rHours, rMinutes, 
    	rSecs, digit_height, digit_width, colon_width,applet_width, 
    	applet_height ;
    int[] image_start_x ;
    boolean tminus = false;
    Image digit_image[], buffer_image, colon_image, frame_image, 
    	  tminus_image, tplus_image, blank_image ;
    Graphics gc ;

    public countdown()
    {

        digit_image = new Image[10];
        digit_height = 21;
        digit_width = 16;
        colon_width = 9;
        applet_width = 203;
        applet_height = 42;
        image_start_x = new int[14];

    }

    int getParameter(String s1, int s2) 
    {

        String s = getParameter(s1) ;
        return (s != null) ? Integer.parseInt(s) : s2 ;

    }

    String getParameter(String s1, String s2)
    {
  
        String s = getParameter(s1) ;
        return (s != null) ? s : s2 ;
  
    }

    Color getParameter(String s1, Color s2)
    {

        String s = getParameter(s1);
        return (s != null) ? new Color(Integer.parseInt(s, 16)):s2;
  
    }

    public void init()
    {
 
        tracker = new MediaTracker(this);
        try
        {
 
            saying = getParameter("text");
            font = getParameter("font");
            try
            {
  
                dest = new URL(getDocumentBase(), 
                	getParameter("dest", "http://127.0.0.1"));
  
            }
            catch(MalformedURLException _ex) {}
            t_year = Integer.parseInt(getParameter("YEAR"));
            t_month = Integer.parseInt(getParameter("MONTH"));
            t_day = Integer.parseInt(getParameter("DAY"));
            t_hours = getParameter("HOUR", 0);
            t_mins = getParameter("MINUTE", 0);
            t_secs = getParameter("SECOND", 0);
            tz_offset = getParameter("TIMEZONE", 0);
            t_daylight = getParameter("DAYLIGHT", 0);
 
        }
        catch(Exception _ex) { return; }
        image_start_x[0] = 0;
        image_start_x[1] = digit_width;
        image_start_x[2] = digit_width * 2;
        for(int i = 2; i < 14; i++)
            if(i == 6 || i == 9 || i == 12)
                image_start_x[i] = image_start_x[i-1]+colon_width;
            else
                image_start_x[i] = image_start_x[i-1]+digit_width;

        for(int j = 0; j < 10; j++)
        {

            digit_image[j] = getImage(getCodeBase(),
            			 j + font + ".gif");
            tracker.addImage(digit_image[j], 0);
 
        }

        colon_image = getImage(getCodeBase(), "c_" + font + ".gif");
        tracker.addImage(colon_image, 1);
        tminus_image = getImage(getCodeBase(), "tm_" 
        			+ font + ".gif");
        tracker.addImage(tminus_image, 2);
        tplus_image = getImage(getCodeBase(), "tp_" 
        			+ font + ".gif");
        tracker.addImage(tplus_image, 3);
        blank_image = getImage(getCodeBase(), "b_" 
        			+ font + ".gif");
        tracker.addImage(blank_image, 4);
        try
        {

            buffer_image = createImage(applet_width, applet_height);
            gc = buffer_image.getGraphics();
            return;
 
        }
        catch(Exception _ex) {}
        gc = null;
    
    }

    public void paintDigClk(Graphics g)
    {
   
        int j = 0;
        int i1 = 0;
        Date date = new Date();
        int i = date.getSeconds();
        if(totalSec == -1) tminus = false;
        if(tminus) 
          g.drawImage(tminus_image, image_start_x[i1++], 0, this);
        else 
          g.drawImage(tplus_image, image_start_x[i1++], 0, this);
        if(i != j)
        {
          
            totalSec--;
            int l = Math.abs(totalSec);
            rDays = (int)Math.floor((double)l / 86400D);
            rHours = (int)Math.floor((double)(l % 0x15180) / 3600D);
            rMinutes = (int)Math.floor((double)(l % 3600) / 60D);
            rSecs = l % 60;
            if(rDays / 1000 != 0)
                g.drawImage(digit_image[rDays / 1000], 
                	image_start_x[i1++], 0, this);
            else
                g.drawImage(blank_image, image_start_x[i1++], 
                	0, this);
            g.drawImage(digit_image[(rDays % 1000) / 100], 
            		image_start_x[i1++], 0, this);
            g.drawImage(digit_image[(rDays % 100) / 10], 
            		image_start_x[i1++], 0, this);
            g.drawImage(digit_image[rDays % 10], 
            		image_start_x[i1++], 0, this);
            g.drawImage(colon_image, 
            		image_start_x[i1++], 0, this);
            g.drawImage(digit_image[rHours / 10], 
            		image_start_x[i1++], 0, this);
            g.drawImage(digit_image[rHours % 10], 
            		image_start_x[i1++], 0, this);
            g.drawImage(colon_image, image_start_x[i1++], 0, this);
            g.drawImage(digit_image[rMinutes / 10], 
            		image_start_x[i1++], 0, this);
            g.drawImage(digit_image[rMinutes % 10], 
            		image_start_x[i1++], 0, this);
            g.drawImage(colon_image, image_start_x[i1++], 0, this);
            g.drawImage(digit_image[rSecs / 10], 
            		image_start_x[i1++], 0, this);
            g.drawImage(digit_image[rSecs % 10], 
            		image_start_x[i1++], 0, this);
        
        }
    
    }

    public void start()
    {
      
        int ai[][] = {
        	
            {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
            {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
            {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31},
            {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}
        
        };
        int ai1[] = {366, 365, 365, 365};
        int l2 = 0;
        int i3 = 0;
        int j3 = 0;
        Date date = new Date();
        int k = date.getSeconds();
        int j = date.getMinutes();
        int i = date.getHours();
        int l = date.getMonth();
        l++;
        int i1 = date.getDate();
        int j1 = date.getYear();
        j3 = date.getTimezoneOffset();
        j1 += 1900;
        boolean flag = false;
        int k2 = 0x15180;
        i3 += t_secs;
        i3 += t_mins * 60;
        i3 += t_hours * 60 * 60;
        i3 += (t_day - 1) * k2;
        for(int k1 = 1; k1 < t_month; k1++)
            i3 += ai[t_year % 4][k1 - 1] * k2;

        i3 += tz_offset * 60;
        for(int l1 = 1970; l1 < t_year; l1++)
            i3 += ai1[l1 % 4] * k2;

        if(t_daylight == 1) i3 -= 3600;
        l2 += k;
        l2 += j * 60;
        l2 += i * 60 * 60;
        l2 += (i1 - 1) * k2;
        for(int i2 = 1; i2 < l; i2++)
            l2 += ai[j1 % 4][i2 - 1] * k2;

        for(int j2 = 1970; j2 < j1; j2++)
            l2 += ai1[j2 % 4] * k2;

        if(flag) l2 -= 3600;
        l2 += tz_offset * 60;
        totalSec = i3 - l2;
        if(tz_offset != 0) totalSec += j3 * 60;
        if(totalSec <= 0) tminus = false;
        else tminus = true;
        rDays = totalSec / 0x15180;
        rHours = (totalSec % 0x15180) / 3600;
        rMinutes = (totalSec % 3600) / 60;
        rSecs = totalSec % 60;
        if(timer == null)
        {
 
            timer = new Thread(this);
            timer.start();
  
        }
  
    }

    public void stop()
    {
 
        timer = null;
 
    }

    public void run()
    {
  
        try
        {

            tracker.waitForID(0);
            tracker.waitForID(1);
            tracker.waitForID(2);
            tracker.waitForID(3);
 
        }
        catch(InterruptedException _ex) { return; }
        while(timer != null)
        {
 
            try
            {
 
                Thread.sleep(1000L);
 
            }
            catch(InterruptedException _ex) { }
            repaint();
 
        }
 
    }

    public void update(Graphics g)
    {
 
        if(buffer_image != null)
        {
 
            paintDigClk(gc);
            g.drawImage(buffer_image, 0, 0, this);
            return;
 
        }
        else
        {
 
            g.clearRect(0, 0, applet_width, applet_height);
            paintDigClk(g);
            return;
 
        }
 
    }

    public boolean mouseEnter(Event event, int i, int j)
    {
 
        showStatus(saying);
        return true;
 
    }

    public boolean mouseUp(Event event, int i, int j)
    {
 
        getAppletContext().showDocument(dest);
        return true;
 
    }

}