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接着上面的部分，下面是applet主程序部分：
public class myclock extends applet implements runnable
{
static final int background=0; //背景图片的序号，供数组使用
static final int logo=1; //logo图片的序号，供数组使用
static final string javex=”bear”; //表盘上显示的文字
static final double minsec=0.104719755; //分针和秒针在表盘上的刻度（60个）间的弧度
static final double hour=0.523598776; //时针在表盘上的刻度（24个）间的弧度
thread clockthread = null; //使用多线程机制，用另一个线程不断显示图片
//提供的默认参数，如果html文件里面没有给参数就使用
int width = 100;
int height = 100;
color bgcolor = new color(0,0,0);
color facecolor = new color(0,0,0);
color sweepcolor = new color(255,0,0);
color minutecolor = new color (192,192,192);
color hourcolor = new color (255,255,255);
color textcolor = new color (255,255,255);
color casecolor = new color (0,0,0);
color trimcolor = new color (192,192,192);
string logostring=null;
image images[] = new image[2]; //背景和logo的图片
boolean ispainted=false; //如果第一次载入时绘制背景及表盘，其他时候重绘则只绘制指针
//时钟圆心的位置
int x1,y1;
//最上面那个三角形的刻度图形的坐标
int xpoints[]=new int[3], ypoints[]=new int[3];
//保存当前时间，转换成(double)(hours + minutes/60)
hms cur_time;
//秒针、分针、时针
sweephand sweep;
hmhand minutehand,
hourhand;
//用于绘制的时、分、秒
double lasthour;
int lastminute,lastsecond;
//显示日期和表盘上的字母的字体
font font;
//图片显示使用了缓冲机制，offscrimage和offscrgc存放缓冲区内图片的信息
image offscrimage;
graphics offscrgc;
//用于测试背景图片和logo图片
mediatracker tracker;
int mindimension; // 如果背景区域不是正方形的话，保证时钟在中间显示
int originx; // 时钟图形所在正方形区域的左上角x坐标
int originy; // 时钟图形所在正方形区域的左上角y坐标
double tzdifference=0; //时区间的差，向西为负数，向东为正数
boolean localonly=false; //是否只使用本地时间，如果为false则可以根据传入的时区显示该时区时间
//保存参数的类型说明
public string[][] getparameterinfo()
{
string[][] info = {
{“width”, “int”, “applet的长度，以象素为单位”},
{“height”, “int”, “applet的宽度，以象素为单位”},
{“bgcolor”, “string”, “背景颜色，e.g ff0000”},
{“facecolor”, “string”, “表盘颜色”},
{“sweepcolor”, “string”, “秒针颜色”},
{“minutecolor”, “string”, “分针颜色”},
{“hourcolor”, “string”, “时针颜色”},
{“textcolor”, “string”, “文本颜色”},
{“casecolor”, “string”, “框内颜色”},
{“trimcolor”, “string”, “空白区颜色”},
{“bgimageurl”, “string”, “背景图片地址”},
{“logostring”, “string”, “logo字符”},
{“logoimageurl”,”string”, “logo图片地址”},
{“timezone”, “real”, “时区间的差”},
{“localonly”, “int”, “是否考虑到时区差别”}
};
return info;
}
//显示信息
public string getappletinfo()
{
return “版权所有，copy必究，保护正版，人人有责”;
}
void showurlerror(exception e)
{
string errormsg = “url错误：”+e;
showstatus(errormsg);
system.err.println(errormsg);
}
//相当于把时钟变成100×100的大小，percent即相对坐标
private int size(int percent)
{
return (int)((double)percent/100.0 * (double)mindimension);
}
public void init()
{
url imagesurl[] = new url[2];
string szimagesurl[] = new string[2];
tracker = new mediatracker(this);
//得到html页面提供的参数，并把它转换相应的格式
string paramstring = getparameter( “width” );
if( paramstring != null )
width = integer.valueof(paramstring).intvalue();
paramstring = getparameter( “height” );
if( paramstring != null )
height = integer.valueof(paramstring).intvalue();
paramstring = getparameter( “timezone” );
if( paramstring != null )
tzdifference = double.valueof(paramstring).doublevalue();
paramstring = getparameter( “localonly” );
if( paramstring != null && integer.valueof(paramstring).intvalue() != 0){
localonly=true;
tzdifference=0.;
}
paramstring = getparameter( “bgcolor”);
if( paramstring != null )
bgcolor=parsecolorstring(paramstring);
paramstring = getparameter( “facecolor”);
if( paramstring != null )
facecolor=parsecolorstring(paramstring);
paramstring = getparameter( “sweepcolor”);
if( paramstring != null )
sweepcolor=parsecolorstring(paramstring);
paramstring = getparameter( “minutecolor”);
if( paramstring != null )
minutecolor=parsecolorstring(paramstring);
paramstring = getparameter( “hourcolor”);
if( paramstring != null )
hourcolor=parsecolorstring(paramstring);
paramstring = getparameter( “textcolor”);
if( paramstring != null )
textcolor=parsecolorstring(paramstring);
paramstring = getparameter( “casecolor”);
if( paramstring != null )
casecolor=parsecolorstring(paramstring);
paramstring = getparameter( “trimcolor”);
if( paramstring != null )
trimcolor=parsecolorstring(paramstring);
logostring = getparameter( “logostring”);
if( logostring == null )
logostring=javex;
else if(logostring.length() > 8)
logostring= logostring.substring(0,8); //限制8个字母，否则显示不下!
//szimagesurl数组根据html传入参数存放图片的文件名
szimagesurl[background] = getparameter(“bgimageurl”);
szimagesurl[logo] = getparameter(“logoimageurl”);
//测试图片
for(int i=0; i<2; i++){
if(szimagesurl[i] != null){
//根据codebase参数与image文件名得到image的路径，测试是否存在，如果不存在就不用图片
try{
imagesurl[i]=new url(getcodebase(),szimagesurl[i]);
} catch (malformedurlexception e)
{
showurlerror(e);
imagesurl[i]=null;
images[i]=null;
}
if(imagesurl[i] != null){
showstatus(“加载图片: ” + imagesurl[i].tostring());
images[i]=getimage(imagesurl[i]);
if(images[i] != null)
tracker.addimage(images[i],i);
showstatus(“”);
}
try{
tracker.waitforall(i);
}catch (interruptedexception e){}
}
else images[i]=null;
}
//得到相应时区的时间
cur_time=(localonly)? new hms() : new hms(tzdifference);
lasthour=-1.0;
lastminute=-1;
lastsecond=-1;
x1=width/2;
y1=height/2;
//换算出圆形时钟在背景里的左上角坐标
mindimension= math.min(width, height);
originx=(width-mindimension)/2;
originy=(height-mindimension)/2;
//计算出上面三角形的三个点的坐标
xpoints[1]=x1-size(3); xpoints[2]=x1+size(3); xpoints[0]=x1;
ypoints[1]=y1-size(38);ypoints[2]=y1-size(38); ypoints[0]=y1-size(27);
//计算出秒针、分针、时针图形的各个点坐标
sweep=new sweephand(x1,y1,size(40),3);
minutehand=new hmhand(x1,y1,size(40),size(6),6);
hourhand=new hmhand(x1,y1,size(25),size(8),6);
//构造字体
font=new font(“txt”,font.bold,size(10));
//构造缓冲区内图形
offscrimage = createimage(width,height);
offscrgc = offscrimage.getgraphics();
system.out.println(getappletinfo());
}
public void start() //开始启动显示线程
{
if(clockthread == null){
clockthread = new thread(this);
}
clockthread.start();
}
public void stop() //停止显示
{
clockthread = null;
}
private void drawhands(graphics g)
{
double angle;
int i,j;
int x,y;
angle=minsec * lastsecond; //根据lastsecond算出秒针相对于12点刻度的角度
sweep.draw(facecolor, angle, g);//画出秒针
//如果时与分改变则重绘时针分针
if(cur_time.getminutes() != lastminute){
minutehand.draw(facecolor,minsec*lastminute,g);
if(cur_time.get_hours() != lasthour)
hourhand.draw(facecolor,hour*lasthour,g);
}
g.setcolor(textcolor);
g.fillrect(originx+size(12),y1-size(2),size(10),size(4)); //绘制左侧横条
g.fillrect(x1-size(2),originy + mindimension-size(22),size(4),size(10)); //绘制下面的横条
g.fillpolygon( xpoints, ypoints, 3); //绘制顶部的三角形
for(i=1;i<12;i+=3) //在表盘的2、3、5、6、8、9、11时针刻度区绘制圆
for(j=i;j<i+2;j++){
x=(int)(x1+math.sin(hour*j)*size(35));
y=(int)(y1-math.cos(hour*j)*size(35));
g.filloval(x-size(3),y-size(3),size(6),size(6));
}
//设置字体
g.setfont(font);
fontmetrics fm=g.getfontmetrics();
//画顶部的logo字符串
g.drawstring(logostring,x1-fm.stringwidth(logostring)/2,y1-size(12));
//得到日期
string day=integer.tostring(cur_time.getdate(),10);
//将日期绘制在表盘右侧
g.drawstring( day,
originx + mindimension-size(14)-fm.stringwidth(day),
y1+size(5));
//外面画上框子
g.drawrect( originx + mindimension-size(14)-fm.stringwidth(day)-size(2),
y1-size(5)-size(2),
fm.stringwidth(day)+size(4),
size(10)+size(4));
if(images[logo] != null){ //如果logo图片存在，在底部画出来
x = originx + (mindimension-images[logo].getwidth(this))/2;
y = y1 + (mindimension/2 – size(22) – images[logo].getheight(this))/2;
if(x > 0 && y > 0)
offscrgc.drawimage(images[logo], x, y, this);
}
lasthour=cur_time.get_hours();
hourhand.draw(hourcolor,hour*lasthour,g); //画时针
lastminute=cur_time.getminutes();
minutehand.draw(minutecolor,minsec*lastminute,g); //画分针
g.setcolor(minutecolor); //绘制分针尾部的圆形
g.filloval(x1-size(4),y1-size(4),size(8),size(8));
g.setcolor(sweepcolor); //绘制秒针尾部的圆形
g.filloval(x1-size(3),y1-size(3),size(6),size(6));
lastsecond=cur_time.getseconds(); //得到新的秒数，重画
angle=minsec*lastsecond;
sweep.draw(sweepcolor, angle,g);
g.setcolor(trimcolor);
g.filloval(x1-size(1),y1-size(1),size(2),size(2)); //秒针尾部圆心部分应该是螺丝，挖空处理^_^
}
private color parsecolorstring(string colorstring) //参数传入为字符串形（规定为16进制6位字符串）
{
if(colorstring.length()==6){
int r = integer.valueof(colorstring.substring(0,2),16).intvalue(); //前两位为r值
int g = integer.valueof(colorstring.substring(2,4),16).intvalue(); //中间为g值
int b = integer.valueof(colorstring.substring(4,6),16).intvalue(); //最后为b值
return new color(r,g,b); //得到color
}
else return color.lightgray; //字符串不符合规范，默认为灰色
}
public void run()
{
repaint(); //每次启动时首先重绘一次
//每隔500ms获得现在时间并重绘一次
while(null != clockthread){
cur_time= (localonly)? new hms() :new hms(tzdifference);
repaint();
try{
thread.sleep(500);
} catch (interruptedexception e) {}
}
}
public void paint(graphics g) //首先绘制缓冲区内图片，再显示出来
{
int i,x0,y0,x2,y2;
//如果没有提供背景图片，则用bgcolor绘制背景
if(images[background] == null){
offscrgc.setcolor(bgcolor);
offscrgc.fillrect(0,0,width,height);
}
else //否则直接使用背景图片
offscrgc.drawimage(images[background], 0, 0, this);
//绘制外框到表盘间的部分
offscrgc.setcolor(casecolor);
//将园形的范围适量缩减（不充满整个区域），防止有些地方被截取
offscrgc.filloval( originx+1,
originy+1,
mindimension-2,
mindimension-2);
//绘制表盘
offscrgc.setcolor(facecolor);
offscrgc.filloval( originx + size(5),
originy + size(5),
mindimension – size(10),
mindimension – size(10));
//绘制外框线
offscrgc.setcolor(trimcolor);
offscrgc.drawoval( originx+1,
originy+1,
mindimension-2,
mindimension-2);
//绘制内框线
offscrgc.drawoval( originx + size(5),
originy + size(5),
mindimension – size(10),
mindimension – size(10));
offscrgc.setcolor(textcolor);
//画刻度，一共有60个刻度，x0、y0为刻度起始的位置，x1、y1圆心位置，x2、y2为刻度终止位置（x0<x2，y0<y2）
for(i=0;i<60;i++){
if(i==0 || (i>=5 && i%5 == 0)){ //每5格绘制一条长线（相对圆心）
x0=(int)(x1+size(40)*math.sin(minsec*i));
y0=(int)(y1+size(40)*math.cos(minsec*i));
}
else{ //其他部分绘制短线
x0=(int)(x1+size(42)*math.sin(minsec*i));
y0=(int)(y1+size(42)*math.cos(minsec*i));
}
x2=(int)(x1+size(44)*math.sin(minsec*i));
y2=(int)(y1+size(44)*math.cos(minsec*i));
offscrgc.drawline(x0,y0,x2,y2);
}
drawhands(offscrgc); //绘制指针
g.drawimage(offscrimage,0,0,this); //把生成的缓冲区图形绘制到页面上
ispainted=true; //使下次update时不绘制表盘
}
public synchronized void update(graphics g)
{
if(!ispainted) //绘制表盘
paint(g);
else{ //已经绘制了表盘，只用绘制指针，首先在缓冲区内绘制，然后显示出来
drawhands(offscrgc);
g.drawimage(offscrimage,0,0,this);
}
}
}
一个测试用的html的例子：
<html>
<title>我的时钟程序</title>
<body>
<h2>显示东8区的时间</h2>
<p>
<applet code=”myclock.class” width=”300″ height=”300″>
<param name=”bgcolor” value=”ffffff”>
<param name=”facecolor” value=”ffffff”>
<param name=”sweepcolor” value=”ff0000″>
<param name=”minutecolor” value=”008080″>
<param name=”hourcolor” value=”000080″>
<param name=”textcolor” value=”000000″>
<param name=”casecolor” value=”000080″>
<param name=”trimcolor” value=”c0c0c0″>
<param name=”logoimageurl” value=”java.gif”>
<param name=”timezone” value=”8″>
</p>
</body>
</html>
