java钟表

import java.util.*;import java.awt.*;import java.applet.*;import java.text.*;public class Exam5Test8 extends Applet implements Runnable { private volatile Thread timer; // The thread that displays clock private int lastxs, lastys, lastxm, lastym, lastxh, lastyh; // Dimensions used to draw hands private SimpleDateFormat formatter; // Formats the date displayed private String lastdate; // String to hold date displayed private Font clockFaceFont; // Font for number display on clock private Date currentDate; // Used to get date to display private Color handColor; // Color of main hands and dial private Color numberColor; // Color of second hand and numbers private int xcenter = 80, ycenter = 55; // Center position 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);  clockFaceFont = new Font("Serif", Font.PLAIN, 14);  handColor = Color.blue;  numberColor = Color.darkGray;  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); // Set clock window size } // Paint is the main part of the program //更新时钟的显示时间 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;  }  // Set position of the ends of the hands  xs = (int) (Math.cos(s * Math.PI / 30 - Math.PI / 2) * 45 + xcenter);  ys = (int) (Math.sin(s * Math.PI / 30 - Math.PI / 2) * 45 + ycenter);  xm = (int) (Math.cos(m * Math.PI / 30 - Math.PI / 2) * 40 + xcenter);  ym = (int) (Math.sin(m * Math.PI / 30 - Math.PI / 2) * 40 + ycenter);  xh = (int) (Math.cos((h * 30 + m / 2) * Math.PI / 180 - Math.PI / 2) * 30 + xcenter);  yh = (int) (Math.sin((h * 30 + m / 2) * Math.PI / 180 - Math.PI / 2) * 30 + ycenter);  // Get the date to print at the bottom  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, 5, 125);  }  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);  }  // Draw date and hands  g.setColor(numberColor);  g.drawString(today, 5, 125);  g.drawLine(xcenter, ycenter, xs, ys);  g.setColor(handColor);  g.drawLine(xcenter, ycenter - 1, xm, ym);  g.drawLine(xcenter - 1, ycenter, xm, ym);  g.drawLine(xcenter, ycenter - 1, xh, yh);  g.drawLine(xcenter - 1, ycenter, xh, yh);  lastxs = xs;  lastys = ys;  lastxm = xm;  lastym = ym;  lastxh = xh;  lastyh = yh;  lastdate = today;  currentDate = null; } //描绘出时钟表 public void paint(Graphics g) {  g.setFont(clockFaceFont);  // Draw the circle and numbers  g.setColor(handColor);  g.drawArc(xcenter - 50, ycenter - 50, 100, 100, 0, 360);  g.setColor(numberColor);  g.drawString("9", xcenter - 45, ycenter + 3);  g.drawString("3", xcenter + 40, ycenter + 3);  g.drawString("12", xcenter - 5, ycenter - 37);  g.drawString("6", xcenter - 3, ycenter + 45);  // Draw date and hands  g.setColor(numberColor);  g.drawString(lastdate, 5, 125);  g.drawLine(xcenter, ycenter, lastxs, lastys);  g.setColor(handColor);  g.drawLine(xcenter, ycenter - 1, lastxm, lastym);  g.drawLine(xcenter - 1, ycenter, lastxm, lastym);  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();  } } /*返回有关此 applet 的信息。applet 应该重写此方法，返回包含有关 applet 的作者、版本和版权信息的 String。 Applet 类提供的此方法实现返回 null  */ public String getAppletInfo() {  return "Title: A Clock \n" + "Author: 陈金林, 2011 \n"    + "An analog clock."; } /*返回此 applet 理解的关于参数的信息。applet 应该重写此方法，返回描述这些参数的 String 数组。 数组的每个元素应该是三个 String 的集合，包括名称、类型和描述。  */ 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; }}