java 时钟设计

；；；；；；用Applet小程序写的；；；；；；；；

设计思路：： 画图，先是画指针起点就是圆心，终点是一个可以变的量，用系统获取的时间作为自变量

讲一下重要的，就是计算

package practice1;

import java.applet.Applet;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.sql.Time;
import java.time.chrono.ChronoLocalDate;
import java.util.Calendar;
import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;

import javax.xml.crypto.Data;

import org.w3c.dom.CDATASection;

import practice3.Carculator;

public class ClockApplet extends Applet {
	// 圆的左上角坐标（x,y） 半径为r
	private int x,y,r;
	//刻度的长度
	private int length;
	@Override
	public void init() {
		// TODO Auto-generated method stub
		super.init();
		x = y = 150;
		r = 100;
		length = 10;
		this.resize(new Dimension(500, 500));
	}
	@Override
	public void paint(Graphics g) {
		//画出四个刻度
		g.drawOval(x, y, 2*r, 2*r);
		g.setColor(Color.BLUE);
		//上刻度 0时
		g.drawLine(x+r, y, x+r, y+length);
		//12点的字样，坐标是调整出来的
		g.drawString("12", x+r-length/2, y+2*length+5);
		
		//下刻度 6时
		g.drawLine(x+r, y+r*2, x+r, y+r*2-length);
		//6点的字样，坐标是调整出来的
		g.drawString("6", x+r-2, y+r*2-length-5);
		
		//左刻度 9时
		g.drawLine(x, y+r, x+length, y+r);
		//9点的字样，坐标是调整出来的
		g.drawString("9", x+length+5, y+r+length/2);
		
		//右刻度 3时
		g.drawLine(x+2*r, y+r, x+2*r-length, y+r);
		//3点的字样，坐标是调整出来的
		g.drawString("3", x+2*r-length*2, y+r+length/2);
		//获取当前时间
		Calendar c = Calendar.getInstance();
		int hour = c.get(Calendar.HOUR);
		int minute = c.get(Calendar.MINUTE);
		int second = c.get(Calendar.SECOND);
		String s = new String(hour+":"+minute+":"+second);
		double angle1 = second*Math.PI/30.0;
		double angle2 =  (second/60 + minute)*Math.PI/30.0;
		double angle3 = (minute/60 + hour)*Math.PI/6;
		//画时针、分针、秒针
		//圆心坐标(x+r,y+r)
		
		g.drawString(s, 100, 100);
		g.setColor(Color.RED);
		// TODO Auto-generated method stub
		//秒针
		g.drawLine(x+r, y+r, (int)(x+r+r*Math.sin(angle1)), (int)(x+r-r*Math.cos(angle1)));
		//分针
		g.drawLine(x+r, y+r, (int)(x+r+(r-length)*Math.sin(angle2)), (int)(x+r-(r-length)*Math.cos(angle2)));
		//时针
		g.drawLine(x+r, y+r, (int)(x+r+(r-length*3)*Math.sin(angle3)), (int)(x+r-(r-length*3)*Math.cos(angle3)));
		EXE();
	}
	public void EXE() {
		Timer t = new Timer();
		t.schedule(new TimerTask() {	
			@Override
			public void run() {
				// TODO Auto-generated method stub
				repaint();
			}
		}, 1000);
	}
}