Java-Digital Clock (Simple Edition)

effect:

Code:

package Clock2;

import java.awt.*;
import java.text.DateFormat;
import java.util.*;
import javax.swing.*;
//数字时钟
public class ClockDemo extends JFrame implements Runnable{
    
    
	private static final long serialVersionUID = 1L;
  Thread clock;
  final int Xpoint=180;
  final int Ypoint=180;
  final int R=80;
  int xHour=0,yHour=0,xSecond=0,ySecond=0,xMin=0,yMin=0;
  public ClockDemo()
  {
    
    
     super("数字时钟"); //调用父类构造函数
     setFont(new Font("宋体",Font.BOLD,20)); //设置时钟的显示字体
     start(); //开始进程
     setSize(400,400);  //设置窗口尺寸
     setVisible(true);  //窗口可视


     setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  //关闭窗口时退出程序
 }
public void start()
 {
    
     //开始进程
   if(clock==null)//如果进程为空值
   {
    
    
      clock=new Thread(this); //实例化进程
      clock.start(); //开始进程
   }
 }
public void run()//运行进程
{
    
     
   while (clock!=null)
   {
    
    
      repaint(); //调用paint方法重绘界面
      try
      {
    
    
        Thread.sleep(1000);  //线程暂停一秒(1000毫秒)
      }
      catch (InterruptedException ex){
    
    
      ex.printStackTrace();  //输出出错信息
   }}}

public void stop(){
    
     //停止进程
   clock=null;
}
public void paint(Graphics g) {
    
    //重载组件的paint方法
 
   //Graphics2D g2=(Graphics2D)g;  //得到Graphics2D对象
   DateFormat dateFormat = DateFormat.getDateInstance(DateFormat.FULL);
   Calendar now=new GregorianCalendar(); //实例化日历对象
   now.setTime(new Date());//dateFormat.format(now.getTime())
   String timeInfo=""; //输出信息
   int hour=now.get(Calendar.HOUR_OF_DAY); //得到小时数
   int minute=now.get(Calendar.MINUTE);   //得到分数
   int second=now.get(Calendar.SECOND);  //得到秒数
   if (hour<=9)
      timeInfo+="0"+hour+":"; //格式化输出
   else
      timeInfo+=hour+":";
   if (minute<=9)
      timeInfo+="0"+minute+":";
   else
      timeInfo+=minute+":";
   if (second<=9)
      timeInfo+="0"+second;
   else
       timeInfo+=second;
   g.setColor(Color.yellow);  //设置当前颜色为白色
   Dimension dim=getSize();  //得到窗口尺寸
   g.fillRect(0,0,dim.width,dim.height);  //填充背景色为白色
   g.setColor(Color.red);  //设置当前颜色为橙色
   g.drawString(timeInfo,130,340);  //显示时间字符串
   g.setColor(Color.green);
   g.drawString(dateFormat.format(now.getTime()),20,60);
   g.setColor(Color.black);
   g.setFont(new Font("SAN_SERIF",Font.BOLD,15));
 for(int i=0,num=12;i<360;i+=6)
{
    
     
 double alfa = Math.toRadians(i);
 int xPos=Xpoint+(int)(R*Math.sin(alfa));
 int yPos=Ypoint-(int)(R*Math.cos(alfa));
 if(i==0)
 {
    
    
  if (num%3==0)
   g.setColor(Color.red);  //  数字3,6,9,12为红色
  else
   g.setColor(Color.black);  // 其余数字为黑色
   g.drawString(""+num,xPos-5,yPos+3);  // 写数字
  num=(num+1); 
 }
 else
 {
    
    
  g.setColor(Color.black);
  g.drawString(".",xPos,yPos);
 }
}
 g.setColor(Color.black);
 g.fillOval(Xpoint-4,Ypoint-4,10,10);
 //画秒针
    xSecond=(int)(Xpoint+(R-10)*Math.sin(second*(2*Math.PI/60)));
    ySecond=(int)(Ypoint-(R-10)*Math.cos(second*(2*Math.PI/60)));
    g.setColor(Color.black);
    g.drawLine(Xpoint,Ypoint,xSecond,ySecond);
    //画分针
    xMin=(int)(Xpoint+(R-20)*Math.sin((minute+second/60)*(2*Math.PI/60)));
    yMin=(int)(Ypoint-(R-20)*Math.cos((minute+second/60)*(2*Math.PI/60)));
    g.setColor(Color.red);
    g.drawLine(Xpoint,Ypoint,xMin,yMin);
    //画时针
    xHour=(int)(Xpoint+(R-30)*Math.sin((hour+minute/60+second/60/60)*(2*Math.PI/12)));
    yHour=(int)(Ypoint-(R-30)*Math.cos((hour+minute/60+second/60/60)*(2*Math.PI/12)));
    g.setColor(Color.red);
    g.drawLine(Xpoint,Ypoint,xHour,yHour);
}
public static void main(String[] args)
{
    
    
  new ClockDemo();}}