服务器端发送UDP数据包客户端未收到问题解决

最近跟着马士兵老师学习坦克大战网络版的编写，在昨晚的编写过程中遇到了问题，代码如下，服务器端接收客户端发来的坦克的信息并转发给所有的坦克时，客户端没有收到UDP消息，

1，考虑是客户端的接收udp包的线程没有启动么？于是在线程类UDPRecvThread的run方法中System.out.println（"something"）,运行程序，有输出，说明线程已经启动；

2，初次尝试使用一下debug，正常情况下程序应该输出“a packet received from server”，现在没有输出，考虑将断点设置在输出语句的上一句ds.receive（dp），执行debug，程序执行到receive后再Step over，程序直接结束了，考虑服务器端是否将udp包发出来了

3，服务器端是否将udp包发送出来，在ds.send(dp)后输出一句“a packet sended”，并解析该数据包，执行程序发现有输出语句，解析的包也没有错误，说明客户端的坦克信息包发送成功且数据包没有问题，服务器端也接收成功，出错环节就在服务器往各个客户端发送，

4，查看ArrayList中是否加入了客户端坦克，检查之后也是没有问题

5，没有办法与马老师的源代码逐行对比，对比代码也是没有发现问题

以上就是昨晚的大致思路了，已经1点了，遂洗洗碎了；

闭上眼睛睡不着，整理一下思路，再考虑考虑，问题就出在服务端发往客户端的过程中，客户端没收到，服务端的发送地址是否写对了，这个以上没有考虑，服务端在发送udp包之前有对udp包重新设置IP和端口，取的是坦克的IP和端口，应该没错，那坦克将自身的IP和端口传送给服务端时有没有出错呢？明天检查吧

今晚回来第一时间查看端口设置，服务器端中start方法中readInt进来的udpPort也没有错；

在往下看问题出在保存坦克IP和端口的类中，

Client c = new Client(IP,udpPort);//new一个类对象

/**
如下是类定义，类的构造方法中由于粗心，udp写成upd
在eclipse中
**/
<pre name="code" class="java">	private class Client{
String IP;
int udpPort;
public Client(String IP , int updPort){
this.IP = IP;
this.udpPort = udpPort;//在eclipse中该句被标了下划波浪线，是个警告，单击后提示“Creat parameter udpPort”，这才发现问题
}
}

//服务器端
import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketException;
import java.util.ArrayList;
import java.util.List;
public class TankServer {

public static final int TCP_PORT = 8888;
public static final int UDP_PORT = 6666;
private static int ID = 100;
List<Client> clients  = new ArrayList<Client>();

public void start(){

new Thread(new UDPThread()).start();
ServerSocket ss = null;
try {
ss = new ServerSocket(TCP_PORT);
} catch (IOException e) {
e.printStackTrace();
}
while(true) {
Socket s = null;
try{
s = ss.accept();
DataInputStream dis = new DataInputStream(s.getInputStream());
int udpPort = dis.readInt();
String IP = s.getInetAddress().getHostAddress();
Client c = new Client(IP,udpPort);
clients.add(c);
DataOutputStream dos = new DataOutputStream(s.getOutputStream());
dos.writeInt(ID++);
System.out.println("a Client is connected:"+s.getInetAddress()+":"+ s.getPort()+"----- udp Port:"+udpPort);
}catch(IOException e){
e.printStackTrace();
}finally{
if(s!=null){
try {
s.close();
s = null;
} catch (IOException e) {
e.printStackTrace();
}

}
}

}
}

public static void main(String[] args) {

new TankServer().start();

}

private class Client{
String IP;
int udpPort;
public Client(String IP , int udpPort){
this.IP = IP;
this.udpPort = udpPort;
}
}

private class UDPThread implements Runnable {

byte[] buf = new byte[1024];

@Override
public void run() {
DatagramSocket ds = null;
try {
ds = new DatagramSocket(UDP_PORT);
} catch (SocketException e) {
e.printStackTrace();
}
System.out.println("UDP thread started at port :"+ UDP_PORT);
while(ds!=null){
DatagramPacket dp = new DatagramPacket(buf,buf.length);
try {
ds.receive(dp);
for(int i=0;i<clients.size();i++){
Client c = clients.get(i);
dp.setSocketAddress(new InetSocketAddress(c.IP,c.udpPort));
ds.send(dp);
System.out.println("a packet sended");
}

} catch (IOException e) {
e.printStackTrace();
}
}

}

//		private void parse(DatagramPacket dp) {
//			ByteArrayInputStream bais = new ByteArrayInputStream(buf,0,dp.getLength());
//			DataInputStream dis = new DataInputStream(bais);
//			TankNewMsg msg = new TankNewMsg();
//			msg.parse(dis);
//
//		}

}

}

//客户端网络连接类，NetClient
import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.net.SocketException;
import java.net.UnknownHostException;

public class NetClient {

private static int UDP_PORT_START = 2223;
private int udpPort;
TankClient tc;
DatagramSocket ds = null;

public NetClient(TankClient tc){
udpPort = UDP_PORT_START ++;
this.tc = tc;
try {
ds = new DatagramSocket(udpPort);
} catch (SocketException e) {
e.printStackTrace();
}
}

public void connect(String IP, int port) {
Socket s = null;
try {
s = new Socket(IP,port);
DataOutputStream dos = new DataOutputStream(s.getOutputStream());
dos.writeInt(udpPort);
DataInputStream dis = new DataInputStream(s.getInputStream());
int id = dis.readInt();
tc.t.id = id;
System.out.println("connect to server ! ID:"+ id);
} catch (UnknownHostException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}finally{
if(s!=null){
try {
s.close();
s = null;
} catch (IOException e) {
e.printStackTrace();
}
}
}

TankNewMsg msg = new TankNewMsg(tc.t);
send(msg);
new Thread(new UDPRecvThread()).start();
}

public void send(TankNewMsg msg){
msg.send(ds,"localhost",TankServer.UDP_PORT);
}

private class UDPRecvThread implements Runnable{

byte[] buf = new byte[1024];
@Override
public void run() {
while(ds!=null){
DatagramPacket dp = new DatagramPacket(buf,buf.length);
try {
ds.receive(dp);
parse(dp);
System.out.println("a packet received from server");

} catch (IOException e) {
e.printStackTrace();
}
}
}
private void parse(DatagramPacket dp) {
ByteArrayInputStream bais = new ByteArrayInputStream(buf,0,dp.getLength());
DataInputStream dis = new DataInputStream(bais);
TankNewMsg msg = new TankNewMsg();
msg.parse(dis);

}

}
}