import java.awt.*;
import java.applet.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
public class FanControlPanel extends JFrame implements ActionListener{
	
	 Fan vt;
	 Thread th;
	 JPanel mu = new JPanel(); //放置按鈕的面板       
	
	 JButton b[] = new JButton[4];
	 String buttonTitle[]={"start","stop","reverse","accelerate"};
	 public FanControlPanel()
	 {
		 for(int i=0; i<4; i++) {
		 	  	b[i] = new JButton(buttonTitle[i]);
		 	  	mu.add(b[i]);
		 	  	b[i].addActionListener(this);
	 }
		  vt = new Fan();
	 	  this.getContentPane().add(vt,"Center");
	 	  this.getContentPane().add(mu,"North");	 	  	
	 	  setTitle("電風扇");
	 	  setSize(500,500);
	 	  setVisible(true);
	 	}
	 public static void main(String args[])
	   {
	      new FanControlPanel();
	   }
	 
	 public void actionPerformed(ActionEvent e) {
	   	  String s =e.getActionCommand();
	   	  if(s.equals("start"))//啟用多線程
	   	  {
	   		vt.flag=1;
	   		vt.speed=1000;
	   	  	 th= new Thread(vt);
		 	     th.start();
	   	  }
	   	  else if(s.equals("stop")) {//停止多線程
	   	  	 if(th!=null){
	   	  	 	 th.stop();
	   	  	   th=null;
	   	  	 }
	      }
	      else if(s.equals("reverse")) {//re來控制正反角度,從而再給reverse設置監聽
	    	  if(vt.flag==1)
	    	  {
	    		  vt.re=-1;
	    		  vt.flag=0;
	    	  }
	    		  
	    	  else
	    	  {
	    		  vt.re=1;
	    		  vt.flag=1;
	    	  }
	      }
	      else if(s.equals("accelerate")) {
	    	  if(vt.speed>10)
	    		  vt.speed=vt.speed/10;
	    	  if(vt.speed<=10)
	    		  vt.speed=vt.speed/1;
	    	  
	    	  }
	      
	   }
	 
}

class Fan extends JPanel implements Runnable
{
	int ax=0;
	public int re = 1;
	public int speed = 1000;//睡眠時間初始設定,之后每除以10來改變速度,相當于調速度檔
	public int flag ;//flag是記錄正反向的標識符
	public void run()
	{
		while(true) {
	   	 	  try{
	   	 		  ax=ax+re*10;
	   	 	  	 repaint();
	   	 	  	 Thread.sleep(speed);
	   	 	  }catch(Exception e){}
		}
		
	}
	 public void paintComponent(Graphics g1) 
     {
         super.paintComponent(g1); 
         Graphics2D g = (Graphics2D)g1;        
         g.drawOval(100,60,300,300);
          g.setColor(Color.red);            
          g.fillArc(110,68,280,280,ax,30);
          g.fillArc(110,68,280,280,ax+90,30);
          g.fillArc(110,68,280,280,ax+180,30);
          g.fillArc(110,68,280,280,ax+270,30);
     }
	 
}