(原创 by 徐剑生)《Java Swing之利用简单的多线程实现动态时钟》

注：本文仅供学习和交流

以上是截图，下面上代码

第一个类是Circle

package org.xt.util;



import java.awt.Point;



public class Circle {

    private Point centre;

    private int radius;



    public Circle(Point centre, int radius) {

        this.centre = centre;

        this.radius = radius;

    }



    public Point getCentre() {

        return centre;

    }



    public void setCentre(Point centre) {

        this.centre = centre;

    }



    public int getRadius() {

        return this.radius;

    }



    public void setRadius(int radius) {

        this.radius = radius;

    }

}

 

第二个类是Clock

package org.xt.clock;



import java.awt.BasicStroke;

import java.awt.BorderLayout;

import java.awt.Color;

import java.awt.Graphics;

import java.awt.Graphics2D;

import java.awt.RenderingHints;

import java.util.Calendar;



import javax.swing.JComponent;

import javax.swing.JFrame;

import javax.swing.JPanel;



@SuppressWarnings("serial")

public class Clock extends JComponent implements Runnable {

    private int radius;



    public Clock(int radius) {

        this.radius = radius;

    }



    public void paint(Graphics g) {

        Graphics2D g2d = (Graphics2D) g;



　　　　 //这两句话是去除线条锯齿的关键,至于原理笔者也不清楚,这两句是笔者从网络上找来的(就这两句不是自己写的,呵呵)

        g2d.setStroke(new BasicStroke(1.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));

        g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);



　　　　 //钟盘所在的矩形的左上角的坐标

        int clockPlateX = 0;

        int clockPlateY = 0;

        g2d.setColor(Color.GRAY);



　　　　 //画两个同心圆盘,作为时钟的边框

        g2d.drawOval(clockPlateX, clockPlateY, this.radius * 2, this.radius * 2);

        g2d.drawOval(clockPlateX + 5, clockPlateY + 5, this.radius * 2 - 10, this.radius * 2 - 10);



　　　　 //圆心坐标

        int centreX = this.radius;

        int centreY = centreX;



        g2d.setStroke(new BasicStroke(0.8f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));



　　　　 //这是钟盘中心的那个点

        g2d.fillOval(centreX - 3, centreY - 3, 6, 6);



        g2d.setStroke(new BasicStroke(2.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));



　　　　 //以下开始画大刻度,共有12个,表示有12个小时,基准是9时所指的刻度

        double degree = 0;

        double radian = Math.toRadians(degree);

        for (int i = 0; i < 12; ++i) {



　　　　　　　//计算刻度线相对位置位于左边的点

            int leftX = (int) ((double) centreX - (this.radius - 15) * Math.cos(radian));

            int leftY = (int) ((double) centreY - (this.radius - 15) * Math.sin(radian));



　　　　　　　//计算刻度线相对位置位于右边的点

            int rightX = (int) ((double) centreX - (this.radius - 25) * Math.cos(radian));

            int rightY = (int) ((double) centreY - (this.radius - 25) * Math.sin(radian));

　　　　　　

            g2d.drawLine(leftX, leftY, rightX, rightY);

            degree += 30;

　　　　　　　//将角度转换为弧度

            radian = Math.toRadians(degree);

        }



        g2d.setStroke(new BasicStroke(1.5f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));

　　　　　

        //以下开始画小刻度,共有60-12=48个,基准是0时所指的刻度

        degree = 0;

        radian = Math.toRadians(degree);

        for (int i = 0; i < 60; ++i) {

　　　　     //此条件在于避免小刻度和大刻度重复

            if (i != 0 && degree % 30 != 0) {

                int leftX = (int) ((double) centreX - (this.radius - 15) * Math.cos(radian));

                int leftY = (int) ((double) centreY - (this.radius - 15) * Math.sin(radian));

                int rightX = (int) ((double) centreX - (this.radius - 17) * Math.cos(radian));

                int rightY = (int) ((double) centreY - (this.radius - 17) * Math.sin(radian));

                g2d.drawLine(leftX, leftY, rightX, rightY);

            }

　　　　　　  //每次增加6度

            degree += 360 / 60;

            //将角度转换为弧度

            radian = Math.toRadians(degree);

        }



　　　　 //获取当前的时,分,秒(Date类已经被淘汰,这里使用Calendar)

        Calendar cal = Calendar.getInstance();

        int second = cal.get(Calendar.SECOND);

        int minute = cal.get(Calendar.MINUTE);

        int hour = cal.get(Calendar.HOUR_OF_DAY);

        if (hour > 12) {

            hour = hour % 12;

        }



　　　　 //计算秒针当前距离开始位置的弧度,其余两句分别是分针和时针

        double secondProp = Math.toRadians(second * (360 / 60));

        double minuteProp = Math.toRadians(minute * (360 / 60));

        double hourProp = Math.toRadians((hour + minuteProp / (2 * Math.PI)) * (360 / 12));



        int leftX = (int) (centreX + (this.radius - 25) * Math.sin(secondProp));

        int leftY = (int) (centreY - (this.radius - 25) * Math.cos(secondProp));

        g2d.setStroke(new BasicStroke(1.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));

        g.drawLine(leftX, leftY, centreX, centreY);



        leftX = (int) (centreX + (this.radius - 45) * Math.sin(minuteProp));

        leftY = (int) (centreY - (this.radius - 45) * Math.cos(minuteProp));

        g2d.setStroke(new BasicStroke(1.5f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));

        g.drawLine(leftX, leftY, centreX, centreY);



        leftX = (int) (centreX + (this.radius - 70) * Math.sin(hourProp));

        leftY = (int) (centreY - (this.radius - 70) * Math.cos(hourProp));

        g2d.setStroke(new BasicStroke(2.5f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_BEVEL));

        g.drawLine(leftX, leftY, centreX, centreY);

    }



    public void run() {

        while (true) {

            try {

                Thread.sleep(1000);

            } catch (InterruptedException e) {

                e.printStackTrace();

            }

            this.repaint();

        }

    }



    public static void main(String[] args) {

        JFrame frame = new JFrame();

        JPanel panel = new JPanel(new BorderLayout());

        frame.setContentPane(panel);

        Clock clock = new Clock(150);

        new Thread(clock).start();

        panel.add(clock, BorderLayout.CENTER);

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frame.setSize(600, 400);

        frame.setVisible(true);

    }

}

 

呵呵，水平有限，代码写的比较乱

 

——写于2014-09-08 20:30:00上下