//时钟。
import java.awt.*;
import java.util.*;
import javax.swing.*;
class Coordinate
{
public int x;
public int y;
public void set(int x,int y)
{
this.x=x;
this.y=y;
}
public Coordinate(int x,int y)
{
set(x,y);
}
}
public class ChenWin12 extends JApplet implements Runnable{
Graphics g;
FontMetrics font_metrics;
Thread my_thread;
static final double pi=Math.PI;
static final double _2pi=2*pi;
int width;
int height;
Date current_time;
Coordinate center;
int radius=85;
int inside_radius;
int h_len;
int m_len;
int s_len;
public void init()
{
g=getGraphics();
center=new Coordinate(100,100);
current_time=new Date();
set_defaults();
paint(g);
}
void set_defaults()
{
width=getSize().width;
height=getSize().height;
if(width
else
width=height;
center.set(width/2,height/2);
radius=(width*8)/20;
h_len=(radius*3)/10;
m_len=(radius*4)/10;
s_len=(radius*6)/10;
inside_radius=(radius*7)/10;
Font font=new Font("TimesRoman",Font.BOLD,width/8);
g.setFont(font);
font_metrics=g.getFontMetrics();
}
public void start()
{
if(my_thread==null)
{
my_thread=new Thread(this);
my_thread.start();
}
}
public void stop()
{
if(my_thread!=null)
my_thread=null;
}
public void run()
{
while(my_thread!=null)
{
repaint();
try
{
Thread.sleep(1000);
}
catch(InterruptedException e){}
}
}
public void update(Graphics g)
{
g.setColor(Color.yellow);
g.fillOval(center.x-inside_radius,center.y-inside_radius,
inside_radius*2,inside_radius*2);
current_time=new Date();
GregorianCalendar calendar=new GregorianCalendar();
calendar.setTime(current_time);
int hours=calendar.get(Calendar.SECOND);
int minutes=calendar.get(Calendar.MINUTE);
int seconds=calendar.get(Calendar.HOUR);
// int hours=current_time.getHours();
// int minutes=current_time.getMinutes();
// int seconds=current_time.getSeconds();
g.setColor(Color.black);
draw_hands(hours,minutes,seconds);
}
void draw_hands(int h,int m,int s)
{
int x=center.x;
int y=center.y;
double hour_value=h+m/60.0+s/3600.0;
hour_value*=_2pi/12.0;
g.drawLine(x,y,(int)(x+h_len*Math.sin(hour_value)),
(int)(y-h_len*Math.cos(hour_value)));
g.drawLine(x,y-1,(int)(x+h_len*Math.sin(hour_value)),
(int)(y-h_len*Math.cos(hour_value)));
double minute_value=m+s/60.0;
minute_value*=_2pi/60.0;
g.drawLine(x,y,(int)(x+m_len*Math.sin(minute_value)),
(int)(y-m_len*Math.cos(minute_value)));
g.drawLine(x,y-1,(int)(x+m_len*Math.sin(minute_value)),
(int)(y-m_len*Math.cos(minute_value)));
double second_value=s*_2pi/60.0;
g.drawLine(x,y,(int)(x+s_len*Math.sin(second_value)),
(int)(y-s_len*Math.cos(second_value)));
g.drawLine(x,y-1,(int)(x+s_len*Math.sin(second_value)),
(int)(y-s_len*Math.cos(second_value)));
}
void draw_string(String string,int x,int y)
{
int string_width=font_metrics.stringWidth(string);
int string_height=font_metrics.getAscent();
g.drawString(string,x-string_width/2,y+string_height/2);
}
public void paint(Graphics g)
{
set_defaults();
g.setColor(Color.black);
g.fillRect(0,0,getSize().width,getSize().height);
g.setColor(Color.lightGray);
g.fillOval(0,0,width,height);
g.setColor(Color.black);
for(int i=1;i<=12;i++)
draw_string(""+i,(int)(center.x+(radius-8)*Math.sin(_2pi*
i/12)),
(int)(center.y-(radius-8)*Math.cos(_2pi*i/12)));
for(int j=0;j<60;j++)
draw_string(".",(int)(center.x+(radius+23)*Math.sin(_2pi*
j/60)),
(int)(center.y-8-(radius+23)*Math.cos(_2pi*j/60)));
}
}
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