public void sendClients(){	//Sending contact list
		
        try {
                    Iterator iter = clients.iterator();
                        while (iter.hasNext()) {
                        System.out.println("Contact server:  " + iter.next());
                        }
                       
            oos = new ObjectOutputStream(client.getOutputStream());
            oos.writeObject(clients);
            oos.flush();
               
		} catch (IOException e) {
                    System.err.println("Error : Cannot send the contacts list :" +e.getMessage());
		}
	}