ref:http://blog.chinaunix.net/uid-20771867-id-3416509.html
???????? cmd：telnet localhost 5554
??????? redir add udp:8002:8001 (將PC 8002端口映射為模擬器 8001端口)
???????? 模擬器-SERVER：ServerSocket server = new ServerSocket(8001);//zcl:7100改為2888
??????????? public static void ReceiveUDP() throws IOException {
???????????? // TODO Auto-generated method stub
ReliableUDP udp = new ReliableUDP(null, "172.17.21.231", 8001, 8001);
???????????? byte[] revBuf = new byte[1024];
???????????? int res = udp.ReadFixedLength(revBuf, 1);
??????????? }?????????????????????
???????? PC-CLIENT：Socket socket = new Socket("127.0.0.1", 8002);?
????????? 《TCP/UDP測試工具》 UDP:127.0.0.1 port 8002 (注意：8002是PC的映射端口)?

ok?——》?最終找到原因：是redir add會搶占端口:??????????
ok?——》解決方法：環境設置——關鍵是一定要使用remotePC，單靠本機無法實現調試
??

+++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++++++++++++++++++++++ localPC + + remotePC ++ ip:172.17.22.8 + + ip:172.17.21.54 ++ redir udp:8002:8001 + + ++ + + ++ +++++++++++++++++++++++++++++ + + ++ + android vm + + + ++ + + + + ++ + + + + ++ + send(DestIP=remotePC, + + + Receive(localPort=8001) ++ + localPort=8001) + + + ++ + DestPort=8001) + + + ++ + -----8001---------------------------------> 8001 -+ + + + + ++ + + + + ++ + Receive(localPort=8001), + + + send( DestIP=localPC ++ + + + + localPort=8001) ++ + + + + DestPort=8002) ++ + + + + ++ + 8001<----------+---8002<----------+-----8001 ++ + + + + ++ + + + + ++ +++++++++++++++++++++++++++++ + + ++ + + ++++++++++++++++++++++++++++++++++++++++++ +++++++++++++++++++++++++++++++++++++++++

ok?——》code：
???public class LEDControlerDriver {
????public static void SendUDP() {
?????// TODO Auto-generated method stub
?????ReliableUDP udp = new ReliableUDP(null, DestIP, 8001, 8001);//to lydsw?前一個8001是模擬器-SERVER port，后一個8001是pc 接收消息的port，注意！不是pc映射給模擬器的端口(8002)
?????String s= "32323213";
?????int res = udp.SendFixedLength(s.getBytes(), s.length());?
?????
????}
????
????public static void ReceiveUDP() throws IOException {
?????// TODO Auto-generated method stub
?????ReliableUDP udp = new ReliableUDP(null, DestIP, 8001, 8001);//to lydsw?前一個8001是模擬器-SERVER port，后一個8001是pc 接收消息的port，注意！不是pc映射給模擬器的端口(8002)
?????byte[] revBuf = new byte[1];
?????int res = udp.ReadFixedLength(revBuf, 1);
????}
?????????????????
???public class ReliableUDP {
????public int SendFixedLength(byte[] sendBuf,int nSendLen){
?????Log.i("UDP Demo", "發送數據(1):");
?????//?check
??????? int res = 1;
??????? if (sendBuf.length!=nSendLen) {
??????return -2;
?????}?
???????
??????? //?create socket
??????? DatagramSocket socket = null;
?????try {
??????socket = new DatagramSocket(null);?? // 指定Null很重要，否則Java會自動隨機選個可用端口來綁定
??????socket.setReuseAddress(true);?//?DatagramSocket的setReuseAddress(true)方法執行后，可以允許多個DatagramSocket
??????????????//?綁定到相同的IP地址和端口，那么發送到此IP地址和端口的數據能夠被復制到多個DatagramSocket
??????socket.setSoTimeout(10000);
??????socket.bind(new InetSocketAddress(this.LocalPort));?
?????} catch (SocketException e) {
??????Log.i("UDP Demo", "SendFixedLength:socket create failed1:"+e.getMessage());
??????return -3;
?????} ????
???????
??????? Log.i("UDP Demo", "發送數據(2):");
??????? // 定義一個用于發送的DatagramPacket對象?
?????? ?DatagramPacket outPacket = null;
??????? try {
??????????????? outPacket = new DatagramPacket(sendBuf , nSendLen? , InetAddress.getByName(this.IPaddr) , this.TargetPort);?
?????????????????? socket.send(outPacket);?
?????????????????? Log.i("UDP Demo", "SendData:UDP發送數據:"+StringHexbyteTransform.bytesToHexString(sendBuf));
?????} catch (IOException e2) {
??????Log.i("UDP Demo", "SendData:io failed:"+e2.toString()+":"+e2.getMessage());
??????res = -52;
?????}??
???????
??????? socket.close();
??????? return res;
????}
???????????????????????????????????????????????????
??????????????????????????????????????????????????
????public int ReadFixedLength(byte[] revBuf,int nRecvLen, int timeout)
????{
?????Log.i("UDP Demo", "Read數據(1):");
?????//?check
??????? int res = 1;
??????? int len = nRecvLen;
??????? if (-1 == nRecvLen) {
??????? ?len = revBuf.length;
?????}?
???????
??????? //?create socket
??????? DatagramSocket socket = null;
?????try {
??????socket = new DatagramSocket(null);?? // 指定Null很重要，否則Java會自動隨機選個可用端口來綁定
??????socket.setReuseAddress(true);?//?DatagramSocket的setReuseAddress(true)方法執行后，可以允許多個DatagramSocket
??????????????//?綁定到相同的IP地址和端口，那么發送到此IP地址和端口的數據能夠被復制到多個DatagramSocket
??????socket.setSoTimeout(timeout);
??????socket.bind(new InetSocketAddress(this.LocalPort));?
?????} catch (SocketException e) {
??????Log.i("UDP Demo", "SendFixedLength:socket create failed1:"+e.getMessage());
??????return -3;
?????} ????
???????
??????? Log.i("UDP Demo", "Read數據(2):");
??????? // 定義一個用于發送的DatagramPacket對象?
?????? ?DatagramPacket inPacket = null;
??????? try {
??????? ??inPacket = new DatagramPacket(revBuf , len);
??????? ??socket.receive(inPacket);?
??????? ??ExpandRevBuffer(revBuf);
?????????????????? Log.i("UDP Demo", "receive:"+StringHexbyteTransform.bytesToHexString(revBuf));?
?????} catch (IOException e2) {
??????Log.i("UDP Demo", "SendData:io failed:"+e2.toString()+":"+e2.getMessage());
??????res = -52;
?????}??
???????
??????? socket.close();
??????? return res;
????}

轉載于:https://www.cnblogs.com/carl2380/p/4212578.html

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