private void writeMessageToOfflineUser(String forUser, String fromUser, String message) {
            ServerLogic sl = new ServerLogic();
            File file = new File("resources/"+forUser+"-"+fromUser+".txt"); 
            String ligne;
            
            Date MessageTime = new Date();
            ArrayList<String> filecontent = new ArrayList();
            
            //wrinting messaging
            addLine(file.getPath(),MessageTime + " : " + message);
            
    }