private void disconnect() {	//pour déconnecter le client proprement
		try { 
			if(sInput != null) sInput.close();
		}
		catch(Exception e) {}
		try {
			if(sOutput != null) sOutput.close();
		}
		catch(Exception e) {}
        try{
			if(socket != null) socket.close();
		}
		catch(Exception e) {}
		
		if(clientUI != null)
			clientUI.connectionFailed();
	}//disconnect