public void sendAndGet(){
		try {
			//Լ̹Ϣ
				String sendBuf = Oz.tankString(clientTank);
				out.println(sendBuf);
				out.flush();
				//ȡҵ̹
				String recvBuf = in.readLine();
				tanks = Oz.getTanks(recvBuf);
				for(Tank t:tanks){
					if( t.getId()==id ){
						clientTank = t;
						break;
					}
				}
				
		} catch (IOException e) {
			System.exit(0);
//			e.printStackTrace();
		} catch(NullPointerException e){
			System.exit(0);
		}
	}