Cannot refer to a non-final variable result inside an inner class

public String controlDoor(final String siteId,String order,final String shutdown,final String loginId,final String ip) throws NumberFormatException, UnknownHostException, IOException{
		if(ip.equals(null) || order.equals(null)){
			log.info("ip地址、设备id、命令不能为空");
			return null;
		}
		
		Socket socket = null;
		try {
			socket = new Socket(ip,Integer.valueOf(Constants.DBMAP.get("WS_DOORLOCK_PORT")));
		} catch (Exception e) {
			log.info("***********连接失败*************"+new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date()));
			return "fail";
		}
		
		 log.info("***********连接已经成功*************"+new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(new Date()));
		 DataInputStream dis = new DataInputStream(socket.getInputStream());
		 DataOutputStream dos = new DataOutputStream(socket.getOutputStream());
		
		// 执行开门动作
		String result = openDoor(siteId, order, loginId, ip, socket, dis, dos);
		
		// 开门成功
		if("true".equals(result))
		{   
			Timer  timer = new Timer();
			// 当开门成功6s后 自动关门
			timer.schedule(new TimerTask() {
				
					@Override
					public void run() {
						String flagString = "false";
						Socket socket = null;
						DataInputStream dis = null;
						DataOutputStream dos = null;
						try
						{
							socket = new Socket(ip,Integer.valueOf(Constants.DBMAP.get("WS_DOORLOCK_PORT")));
							dis = new DataInputStream(socket.getInputStream());
							dos = new DataOutputStream(socket.getOutputStream());
							flagString =closeDoor(siteId, shutdown,loginId, ip, dis, dos, socket);
						}
						catch (UnknownHostException e)
						{
							log.error("第1次关门失败!!");
							e.printStackTrace();
						}
						catch (IOException e)
						{
							log.error("第1次关门失败!!");
							e.printStackTrace();
						}
						finally
						{    
							
							// 如果关门失败 则启动保护线程 继续执行关门动作
							if ("false".equals(flagString)||flagString.endsWith("false"))
							{
								TimeoutThread time = new TimeoutThread(2000,dis);
							    for(int i=1;i<5;i++)
								{   
									try
									{
										Thread.sleep(400);
									} catch (InterruptedException e)
									{
										e.printStackTrace();
									}
									if ("false".equals(flagString)||flagString.endsWith("false")) 
									{  
										try
										{
											socket = new Socket(ip,Integer.valueOf(Constants.DBMAP.get("WS_DOORLOCK_PORT")));
											dis = new DataInputStream(socket.getInputStream());
											dos = new DataOutputStream(socket.getOutputStream());
											flagString = closeDoor(siteId, shutdown,loginId, ip, dis, dos, socket);
											if ("false".equals(flagString)||flagString.endsWith("false")) 
												log.error("第"+(i+1)+"次关门失败!!");
										} 
										catch (NumberFormatException e)
										{
											flagString = "false";