clock.java

java经典的源代码 我非常喜欢这个源代码 对于编程很有好处

import java.util.*;
import java.awt.*;
import java.applet.*;
import java.text.*;
public class clock extends Applet implements Runnable{
  Thread timer;
  int lastxs, lastys, lastxm,lastym, lastxh, lastyh;
  SimpleDateFormat formatter;
  String lastdate;
  Font clockFaceFont;
  Date currentDate;
  Color handColor,numberColor;
  public void init(){
    int x,y;
    lastxs = lastys = lastxm = lastym = lastxh = lastyh = 0;
    formatter = new SimpleDateFormat ("yyyy EEE MMM dd hh:mm:ss ");
    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 (Exception E) {
      }
      try {
        handColor = new Color(Integer.parseInt(getParameter("fgcolor1"),16));
      }
      catch (Exception E) { }
      try {
        numberColor = new Color(Integer.parseInt(getParameter("fgcolor2"),16));
      }
      catch (Exception E) { }
      resize(200,200);              // 设置时钟窗口大小
  }
  public void plotpoints(int x0, int y0, int x, int y, Graphics g){
    g.drawLine(x0+x,y0+y,x0+x,y0+y);
    g.drawLine(x0+y,y0+x,x0+y,y0+x);
    g.drawLine(x0+y,y0-x,x0+y,y0-x);
    g.drawLine(x0+x,y0-y,x0+x,y0-y);
    g.drawLine(x0-x,y0-y,x0-x,y0-y);
    g.drawLine(x0-y,y0-x,x0-y,y0-x);
    g.drawLine(x0-y,y0+x,x0-y,y0+x);
    g.drawLine(x0-x,y0+y,x0-x,y0+y);
  }
  public void circle(int x0, int y0, int r, Graphics g){
    int x,y;
    float d;
    x=0;
    y=r;
    d=5/4-r;
    plotpoints(x0,y0,x,y,g);
    while (y>x) {
      if (d<0) {
        d=d+2*x+3;
        x++;
      }
      else {
        d=d+2*(x-y)+5;
        x++;
        y--;
      }
      plotpoints(x0,y0,x,y,g);
    }
  }
  public void paint(Graphics g){
    int xh, yh, xm, ym, xs, ys, s = 0, m = 10, h = 10, xcenter, ycenter;
    String today;
    currentDate = new Date();
    SimpleDateFormat formatter = new SimpleDateFormat("s",Locale.getDefault());
    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;
    }
    formatter.applyPattern("EEE MMM dd HH:mm:ss yyyy");
    today = formatter.format(currentDate);
    xcenter=80;
    ycenter=55;
    xs = (int)(Math.cos(s * 3.14f/30 - 3.14f/2) * 45 + xcenter);
    ys = (int)(Math.sin(s * 3.14f/30 - 3.14f/2) * 45 + ycenter);
    xm = (int)(Math.cos(m * 3.14f/30 - 3.14f/2) * 40 + xcenter);
    ym = (int)(Math.sin(m * 3.14f/30 - 3.14f/2) * 40 + ycenter);
    xh = (int)(Math.cos((h*30 + m/2) * 3.14f/180 - 3.14f/2) * 30 + xcenter);
    yh = (int)(Math.sin((h*30 + m/2) * 3.14f/180 - 3.14f/2) * 30 + ycenter);
    g.setFont(clockFaceFont);
    g.setColor(handColor);
    circle(xcenter,ycenter,50,g);
    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);
    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);
    }
    g.setColor(numberColor);
    g.drawString("", 5, 125);
    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;
  }
  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(1000);
      }
      catch (InterruptedException e) {
      }
      repaint();
    }
  }
  public void update(Graphics g){
    paint(g);
  }
}