趣味Java编程:Java小时钟编程代码介绍Java认证考试

文章作者 100test 发表时间 2010:01:01 15:44:59
来源 100Test.Com百考试题网

　　/**
　　*
　　*
　　*/
　　//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("小时钟").
　　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.
　　}

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