厉小军《WEB编程技术》源码

/* * Copyright (c) 1999 The Apache Software Foundation. All rights * reserved. */ import java.util.*; import java.awt.*; import java.applet.*; import java.text.*; /** * Time! * * @author Rachel Gollub */ public class Clock2 extends Applet implements Runnable { Thread timer; // The thread that displays clock int lastxs, lastys, lastxm, lastym, lastxh, lastyh; // Dimensions used to draw hands SimpleDateFormat formatter; // Formats the date displayed String lastdate; // String to hold date displayed Font clockFaceFont; // Font for number display on clock Date currentDate; // Used to get date to display Color handColor; // Color of main hands and dial Color numberColor; // Color of second hand and numbers 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 (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(300,300); // Set clock window size } // Plotpoints allows calculation to only cover 45 degrees of the circle, // and then mirror 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); } // Circle is just Bresenham's algorithm for a scan converted circle 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); } } // Paint is the main part of the program 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; // a= s* pi/2 - pi/2 (to switch 0,0 from 3:00 to 12:00) // x = r(cos a) + xcenter, y = r(sin a) + ycenter 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); // Draw the circle and numbers 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); // Erase if necessary, and redraw 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(100); } catch (InterruptedException e) { } repaint(); } } public void update(Graphics g) { paint(g); } public String getAppletInfo() { return "Title: A Clock \nAuthor: Rachel Gollub, 1995 \nAn 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 seconds hand and numbers. Default is dark gray."} }; return info; } }