zhong.java

java的修改时钟的小程序

/*
 * zhong.java
 *
 * Created on 2007年3月22日, 下午8:22
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package zhong;
import java.util.*;
import java.awt.*;
import java.applet.*;
import java.text.*;

public class zhong extends Applet implements Runnable {
    private volatile Thread timer;       // 显示时钟的线程
    private int lastxs, lastys, lastxm,
                lastym, lastxh, lastyh;  // 绘制表针的坐标
    private SimpleDateFormat formatter;  // 格式化日期数据
    private String lastdate;             // 显示日期数据的字符串
    private Font clockFaceFont;          // 显示在钟表数字的字体
    private Date currentDate;            // 存储显示日期的成员属性
    private Color handColor;             // 表针和数字的颜色
    private Color numberColor;           
    private Color HourColor;
    private Color MinuteColor;
    private Color SecondColor;
    private int xcenter = 150, ycenter = 100; // 中心位置（重新设置位置使得表盘变大）
   
    public void init() {
        int x,y;
        lastxs = lastys = lastxm = lastym = lastxh = lastyh = 0;
        formatter = new SimpleDateFormat ("EEE MMM dd hh:mm:ss yyyy", 
                                          Locale.getDefault());
        currentDate = new Date();
        lastdate = formatter.format(currentDate);  //对显示的日期进行格式化
        clockFaceFont = new Font("Serif", Font.PLAIN, 14);
        handColor = Color.blue;
        numberColor = Color.darkGray;
        HourColor = Color.red;  //时针为红色
        MinuteColor = Color.black;  //分针为黑色
        SecondColor = Color.blue;  //秒针为蓝色
        try {
            setBackground(new Color(Integer.parseInt(getParameter("bgcolor"),
                                                     16)));
        } catch (NullPointerException e) {
        } catch (NumberFormatException e) {
        }
        try {
            handColor = new Color(Integer.parseInt(getParameter("fgcolor1"),
                                                   16));
        } catch (NullPointerException e) {
        } catch (NumberFormatException e) {
        }
        try {
            numberColor = new Color(Integer.parseInt(getParameter("fgcolor2"),
                                                     16));
        } catch (NullPointerException e) {
        } catch (NumberFormatException e) {
        }
        resize(300,300);              // 设置钟表窗口大小
    }
    // 绘制钟表的主要部件
    public void update(Graphics g) {
        int xh, yh, xm, ym, xs, ys;
        int s = 0, m = 10, h = 10;
        String today;
        currentDate = new Date();
        formatter.applyPattern("s");
        try {
            s = Integer.parseInt(formatter.format(currentDate));
        } catch (NumberFormatException n) {
            s = 0;
        }
        formatter.applyPattern("m");
        try {
            m = Integer.parseInt(formatter.format(currentDate));
        } catch (NumberFormatException n) {
            m = 10;
        }    
        formatter.applyPattern("h");
        try {
            h = Integer.parseInt(formatter.format(currentDate));
        } catch (NumberFormatException n) {
            h = 10;
        }
        // 设置表针的前端位置（修改参数使得指针变长）
        xs = (int) (Math.cos(s * Math.PI / 30 - Math.PI / 2) * 55 + xcenter);
        ys = (int) (Math.sin(s * Math.PI / 30 - Math.PI / 2) * 55 + ycenter);
        xm = (int) (Math.cos(m * Math.PI / 30 - Math.PI / 2) * 45 + xcenter);
        ym = (int) (Math.sin(m * Math.PI / 30 - Math.PI / 2) * 45 + ycenter);
        xh = (int) (Math.cos((h*30 + m / 2) * Math.PI / 180 - Math.PI / 2) * 40
                   + xcenter);
        yh = (int) (Math.sin((h*30 + m / 2) * Math.PI / 180 - Math.PI / 2) * 40
                   + ycenter);
        // 获得显示在底部的日期数据
        formatter.applyPattern("EEE MMM dd HH:mm:ss yyyy");
        today = formatter.format(currentDate);
        g.setFont(clockFaceFont);
        // Erase if necessary
        g.setColor(getBackground());
        if (xs != lastxs || ys != lastys) {
            g.drawLine(xcenter, ycenter, lastxs, lastys);
            g.drawString(lastdate, 50, 200);
        }
        if (xm != lastxm || ym != lastym) {
            g.drawLine(xcenter, ycenter-1, lastxm, lastym);
            g.drawLine(xcenter-1, ycenter, lastxm, lastym); 
        }
        if (xh != lastxh || yh != lastyh) {
            g.drawLine(xcenter, ycenter-1, lastxh, lastyh);
            g.drawLine(xcenter-1, ycenter, lastxh, lastyh); 
        }
        // 绘制日期和表针
        g.setColor(numberColor);
        g.drawString(today, 50, 200);
        g.setColor(SecondColor);    
        g.drawLine(xcenter, ycenter, xs, ys);  //绘制秒针
        g.setColor(HourColor);
        g.drawLine(xcenter, ycenter-1, xm, ym); //绘制时针
        g.drawLine(xcenter-1, ycenter, xm, ym);
        g.setColor(MinuteColor);
        g.drawLine(xcenter, ycenter-1, xh, yh); //绘制分针
        g.drawLine(xcenter-1, ycenter, xh, yh);
        lastxs = xs; lastys = ys;
        lastxm = xm; lastym = ym;
        lastxh = xh; lastyh = yh;
        lastdate = today;
        currentDate = null;
    }
    public void paint(Graphics g) {
        g.setFont(clockFaceFont);
        // 绘制圆和数字
        g.setColor(handColor);
        g.drawArc(xcenter-75, ycenter-75, 150, 150, 0, 360);  //绘制圆
        g.setColor(numberColor);
        g.drawString("9", xcenter-70, ycenter+3);   //绘制数字
        g.drawString("3", xcenter+65, ycenter+3);
        g.drawString("12", xcenter-5, ycenter-60);
        g.drawString("6", xcenter-3, ycenter+70);
        // 绘制日期和指针
        g.setColor(numberColor); 
        g.drawString(lastdate, 50, 200);
        g.setColor(SecondColor);     
        g.drawLine(xcenter, ycenter, lastxs, lastys);
        g.setColor(HourColor);
        g.drawLine(xcenter, ycenter-1, lastxm, lastym);
        g.drawLine(xcenter-1, ycenter, lastxm, lastym);
        g.setColor(MinuteColor);
        g.drawLine(xcenter, ycenter-1, lastxh, lastyh);
        g.drawLine(xcenter-1, ycenter, lastxh, lastyh); 
    }
    public void start() {
        timer = new Thread(this);
        timer.start();
    }
    public void stop() {
        timer = null;
    }
    public void run() {
        Thread me = Thread.currentThread();
        while (timer == me) {
            try {
                Thread.currentThread().sleep(100);
            } catch (InterruptedException e) {
            }
            repaint();
        }
    }
    public String getAppletInfo() {
        return "Title: A Clock \n"
            + "Author: Rachel Gollub, 1995 \n"
            + "An analog clock.";
    }
    public String[][] getParameterInfo() {
        String[][] info = {
            {"bgcolor", "hexadecimal RGB number", 
             "The background color. Default is the color of your browser."},
            {"fgcolor1", "hexadecimal RGB number", 
             "The color of the hands and dial. Default is blue."},
            {"fgcolor2", "hexadecimal RGB number", 
             "The color of the second hand and numbers. Default is dark gray."}
        };
        return info;
    }
}