implemet Server Listener + chat server + part of client session

src/main/java/com/university/chat/Server/ChatServer.java

@@ -1,12 +1,25 @@
 package com.university.chat.Server;
 
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.Socket;
+
 public class ChatServer {
     // TODO: declare a single shared UserManager instance (static final)
+    private static final UserManager usermanager = new UserManager() ;
     //         This MUST be shared by all ClientSession threads so that
     //         broadcasting and private messaging work correctly.
 
-    public static void main(String[] args) {
+    public static void main(String[] args) throws IOException {
         // TODO: Create a ServerSocket
+        ServerSocket serverSocket = new ServerSocket(8080) ;
+        while (true)
+        {
+            Socket socket = serverSocket.accept() ;
+            ClientSession clientSession = new ClientSession(socket , usermanager) ;
+            Thread thread = new Thread(clientSession) ;
+            thread.start();
+        }
 
         // TODO: In an infinite loop:
         //  accept an incoming client connection