我寫的跟“風(fēng)中過客”差不多，出了點(diǎn)小問題，弄不明白，請老師指教

	public?static?class?UDPThread?extends?Thread{
		DatagramSocket?socket=null;
		DatagramPacket?packet=null;
		public?UDPThread(DatagramSocket?socket,?DatagramPacket?packet)?{
			super();
			this.socket?=?socket;
			this.packet?=?packet;
		}
		
		public?void?run(){
			byte[]?data?=?packet.getData();
			String?info?=?new?String(data,0,packet.getLength());
			System.out.println("我是服務(wù)器,客戶端說："+info);
			
			//響應(yīng)客戶端
			byte[]?data2?=?"歡迎您！".getBytes();
			InetAddress?address?=?packet.getAddress();
			int?port?=?packet.getPort();
			DatagramPacket?packet2?=?new?DatagramPacket(data2,?data2.length,?address,?port);
			try?{
				socket.send(packet2);
			}?catch?(IOException?e)?{
				//?TODO?Auto-generated?catch?block
				e.printStackTrace();
			}
		}
	}

上面沒什么問題，下面的main方法出問題了

	public?static?void?main(String[]?args)?throws?Exception?{
		DatagramSocket?socket?=?new?DatagramSocket(8800);
		byte[]?data?=?new?byte[1024];
		DatagramPacket?packet?=?new?DatagramPacket(data,?data.length);
		System.out.println("******服務(wù)器已經(jīng)啟動******");
		int?count?=?0;
		while(true){
			socket.receive(packet);
			UDPThread?udpThread?=?new?UDPThread(socket,?packet);
			udpThread.start();
			count++;
			System.out.println("客戶端數(shù)量為："+count);
		}
	}

我把

byte[] data = new byte[1024];
DatagramPacket packet = new DatagramPacket(data, data.length);

放在循環(huán)外面

運(yùn)行時(shí)不報(bào)錯，但客戶端發(fā)送請求后，第一次得不到回應(yīng)，發(fā)送第二次請求后，得到第一次的回應(yīng)

但服務(wù)端不顯示接收到的內(nèi)容

我學(xué)“風(fēng)中過客”把這兩句放循環(huán)里 ?就正常了

請問為什么？