/**
　　*
　　* author @;wwwwwwking
　　*
　　*/
　　//package MainPackage;
　　import javax.swing.*;
　　import java.awt.*;
　　import java.awt.geom.*;
　　import java.awt.event.*;
　　import java.util.Calendar;
　　import java.util.GregorianCalendar;
　　/**
　　* This is the main Function of the program.
　　*/
　　public class Clock{
　　public static void main(String []args){
　　ClockFrame frame = new ClockFrame();
　　frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
　　frame.setVisible(true);
　　}
　　}
　　/**
　　* This class is used to define the main frame of the clock
　　*/
　　class ClockFrame extends JFrame{
　　//constructor function
　　public ClockFrame(){
　　setTitle("小時(shí)鐘");
　　setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
　　setLocation(DEFAULT_LOC_WIDTH, DEFAULT_LOC_HEIGHT);
　　ClockPanel panel = new ClockPanel();
　　add(panel);
　　}
　　//variables of the frame
　　private int DEFAULT_LOC_WIDTH = 300;
　　private int DEFAULT_LOC_HEIGHT = 300;
　　private int DEFAULT_WIDTH = 330;
　　private int DEFAULT_HEIGHT = 330;
　　}
　　/**
　　* This class is used to defind the main panel of the clock
　　*/
　　class ClockPanel extends JPanel{
　　public void paintComponent(Graphics g){
　　super.paintComponent(g);
　　Graphics2D g2 = (Graphics2D) g;
　　//get the time of the system
　　GregorianCalendar calendar = new GregorianCalendar();
　　int hour = calendar.get(Calendar.HOUR);
　　int minute = calendar.get(Calendar.MINUTE);
　　int second = calendar.get(Calendar.SECOND);
　　//draw the clock face
　　Ellipse2D clockFace = new Ellipse2D.Double();
　　clockFace.setFrameFromCenter(CENTER_X, CENTER_Y, CENTER_X+RADIUS, CENTER_Y+RADIUS);
　　g2.setColor(Color.BLUE);
　　g2.draw(clockFace);
　　//draw the clock center
　　Ellipse2D clockCenter = new Ellipse2D.Double();
　　clockCenter.setFrameFromCenter(CENTER_X, CENTER_Y, CENTER_X+INNER_RADIUS, CENTER_Y+INNER_RADIUS);
　　g2.setColor(Color.RED);
　　g2.fill(clockCenter);
　　//help to get the exact position of the lines
　　double lenX, lenY, posX, posY;
　　//draw the clock second line
　　Line2D clockSecond = new Line2D.Double();
　　double secondTime = (double) calendar.get(Calendar.SECOND);
　　lenX = SECOND_LEN*Math.sin(2*Math.PI*secondTime/60.0);
　　lenY = SECOND_LEN*Math.cos(2*Math.PI*secondTime/60.0);
　　posX = CENTER_X + lenX;
　　posY = CENTER_Y - lenY;
　　clockSecond.setLine(CENTER_X, CENTER_Y, posX, posY);
　　g2.setColor(Color.PINK);
　　g2.draw(clockSecond);
　　//draw the clock minute line
　　Line2D clockMinute = new Line2D.Double();
　　double minuteTime = (double) calendar.get(Calendar.MINUTE);
　　lenX = MINUTE_LEN*Math.sin(2*Math.PI*(secondTime+60*minuteTime)/3600.0);
　　lenY = MINUTE_LEN*Math.cos(2*Math.PI*(secondTime+60*minuteTime)/3600.0);
　　posX = CENTER_X + lenX;
　　posY = CENTER_Y - lenY;
　　clockMinute.setLine(CENTER_X, CENTER_Y, posX, posY);
　　g2.setColor(Color.GREEN);
　　g2.draw(clockMinute);
　　//draw the clock hour line
　　Line2D clockHour = new Line2D.Double();
　　double hourTime = (double) calendar.get(Calendar.HOUR);
　　lenX = HOUR_LEN*Math.sin(2*Math.PI*((secondTime+60*minuteTime+3600*hourTime)/43200.0));
　　lenY = HOUR_LEN*Math.cos(2*Math.PI*((secondTime+60*minuteTime+3600*hourTime)/43200.0));
　　posX = CENTER_X + lenX;
　　posY = CENTER_Y - lenY;
　　clockHour.setLine(CENTER_X, CENTER_Y, posX, posY);
　　g2.setColor(Color.BLUE);
　　g2.draw(clockHour);
　　int delay = 1000;
　　// actionListener
　　ActionListener drawClock;
　　drawClock=new ActionListener(){
　　public void actionPerformed(ActionEvent evt){
　　repaint();
　　}
　　};
　　//create timer
　　new Timer(delay, drawClock).start();
　　}
　　//variables of the panel
　　private int HOUR_LEN = 50;
　　private int MINUTE_LEN = 70;
　　private int SECOND_LEN = 90;
　　private int RADIUS = 100;
　　private int INNER_RADIUS = 2;
　　private int CENTER_X = 150;
　　private int CENTER_Y = 150;
　　}