code: public static String login(final String _userName,
                                 final String _passwd,
                                 final String _applicationKey)
          throws EFapsException
      {
          String ret = null;
          if (JmsSession.checkLogin(_userName, _passwd, _applicationKey)) {
              final JmsSession session = new JmsSession(_userName);
              JmsSession.CACHE.put(session.getSessionKey(), session);
              ret = session.getSessionKey();
          }
          return ret;
      }
docs: Login and create a Session.
  
  @param _userName         Name of the user to login
  @param _passwd           Password of the user to login
  @param _applicationKey   key of the application that requests
  @return SessionKey if login successful, else null
  @throws EFapsException on error