fan.java

使用netbean开发的电风扇小applet

package myFan;

import java.awt.Graphics;

import javax.swing.JPanel;


public class Fan extends JPanel implements Runnable {

	private static final long serialVersionUID = 1L;
    private int arc=0,direct=1,speed=10;
    boolean flag;
    Thread thread;

    public Fan(){
        thread=new Thread(this);
    }

    public void run(){
        while(true){
            arc+=1;            
            try {
                thread.sleep(100);
                repaint();
                synchronized(thread){
                    if(!flag){
                        thread.wait();
                        flag=true;
                    }
                }
            } catch (InterruptedException ex) {
                ex.printStackTrace();
            }              
        }
    }

    public void start(){
        flag=true;
        thread.start();
    }

    public void reverse(){
       
        direct=direct*-1;

    }

    public void resume(){
        synchronized(thread){
          thread.notify();
        }
    }

    public void stop(){
        flag=false;
    }

    public void changeSpeed(int speed){
        this.speed=speed/2;
    }

	public void paintComponent(Graphics g) {
		super.paintComponent(g);
		int xc = getSize().width /2;
		int yc = getSize().height /2;
		int ra = (int)(Math.min(getSize().width, getSize().height) * 0.4);
		
		int x = xc - ra;
		int y = yc -ra;
		
		g.fillArc(x, y, 2*ra, 2*ra, arc*direct*speed, 30);
		g.fillArc(x, y, 2*ra, 2*ra, arc*direct*speed+90, 30);
		g.fillArc(x, y, 2*ra, 2*ra, arc*direct*speed+180, 30);
		g.fillArc(x, y, 2*ra, 2*ra, arc*direct*speed+270, 30);
	}
}