soockte群聊

Server 代码
package com;
import java.net.*;import java.io.*;import java.util.*;
public class Server { public static void main(String[] args) throws Exception {  ServerSocket server = new ServerSocket(8001);  List<Socket> ss = new ArrayList<Socket>();  while (true) {   Socket socket = server.accept();   ss.add(socket);   new ServerThread1(socket).start();  }  // socket.close();  // server.close(); }}
class ServerThread1 extends Thread { private Socket socket;
public ServerThread1(Socket socket) {  this.socket = socket; }
public void run() {  PrintWriter out = null;  BufferedReader in = null;  try {   out = new PrintWriter(socket.getOutputStream());   in = new BufferedReader(new InputStreamReader(socket     .getInputStream()));
   String s = in.readLine();   System.out.println(s + "上线了");   out.println(s + "上线了");   out.flush();
   s = in.readLine();   while (s != null && !s.equals("quit")) {
    System.out.println(s);
    out.println(s);
    out.flush();
    s = in.readLine();   }  } catch (Exception e) {   e.printStackTrace();  } finally {   try {    in.close();    out.close();    socket.close();   } catch (Exception e) {
   }  } }}
Client代码
package com;
import java.net.*;import java.io.*;
public class Client {
public static void main(String[] args) throws Exception {  Socket socket = new Socket("127.0.0.1", 5001);  //  BufferedReader sin = new BufferedReader(    new InputStreamReader(System.in));  PrintWriter out = new PrintWriter(socket.getOutputStream());  String cname = args[0];  out.println(cname);  out.flush();  new ClientThread1(socket).start();//
  String c = sin.readLine();  while (!c.equals("quit")) {   out.println(cname + "说:" + c);   out.flush();   c = sin.readLine();  }
  out.close();  socket.close(); }}
class ClientThread1 extends Thread { private Socket socket;
public ClientThread1(Socket socket) {  this.socket = socket; }
public void run() {  BufferedReader in = null;  try {   in = new BufferedReader(new InputStreamReader(socket     .getInputStream()));  } catch (IOException e) {   // TODO Auto-generated catch block   e.printStackTrace();  }  while (true) {   String s;   try {    s = in.readLine();    System.out.println(s);   } catch (IOException e) {    // TODO Auto-generated catch block    // e.printStackTrace();    break;   }  } }}
如有错请帮忙改正！