/**
	 * changes the session user including the full login process. any settings made to this session are kept except that
	 * the session cart is assigned to the new session user. if specified the session language and session currency is
	 * changed to the values belonging to the new user ( see {@link User#getSessionLanguage()} and
	 * {@link User#getSessionCurrency()} ). Set the Boolean activateUserLanguageAndCurrency to <code>true</code> if you
	 * want the new user to use his / her default language and currency. If set to <code>false</code>, the new user will
	 * have the language and currency used by the former user.
	 *
	 * @param props
	 *           logging properties ( see {@link LoginProperties} )
	 * @param activateUserLanguageAndCurrency
	 *           if true the session language and session currency are set to the values set at the new user
	 * @throws JaloSecurityException
	 *            in case login process failed
	 * @throws JaloInvalidParameterException
	 *            in case some provided parameter had an unexpected value
	 */
	public void transfer(final Map props, final boolean activateUserLanguageAndCurrency) throws JaloSecurityException,
			JaloInvalidParameterException
	{
		final User newUser;

		if (props != null && props.get(LoginProperties.LOGIN) == null && props.get(LoginProperties.USER_PK) == null
				&& props.get(LoginProperties.LOGIN_TOKEN) != null)
		{
			final LoginToken token = (LoginToken) props.get(LoginProperties.LOGIN_TOKEN);
			newUser = performLogin(token, props);
		}
		else
		{
			newUser = performLogin(props != null ? (String) props.get(LoginProperties.LOGIN) : null, props != null ? (String) props
					.get(LoginProperties.PASSWORD) : null, props);
		}

		setUser(newUser);
		if (activateUserLanguageAndCurrency)
		{
			final Currency userCurr = newUser.getSessionCurrency();
			final Language userLang = newUser.getSessionLanguage();

			if (userCurr != null)
			{
				getSessionContext().setCurrency(userCurr);
			}
			if (userLang != null)
			{
				getSessionContext().setLanguage(userLang);
			}
		}
		// make sure user has a valid language set
		final Language currentLanguage = getSessionContext().getLanguage();

		final Collection activeLanguages = getC2LManager().getActiveLanguages();

		if (activeLanguages.isEmpty())
		{
			throw new JaloSystemException(null, "No active language found for new session of user " + newUser.getLogin()
					+ ". Check restrictions.", 0);
		}

		if (!currentLanguage.isAlive() || !activeLanguages.contains(currentLanguage))
		{
			final Language newLanguage = (Language) activeLanguages.iterator().next();
			log.info("transfering session to user " + newUser.getLogin() + ": forced to switch langanguage to "
					+ newLanguage.getIsoCode());
			getSessionContext().setLanguage(newLanguage);
		}
		// make sure user has a valid currency set
		final Currency currentCurrency = getSessionContext().getCurrency();
		final Collection activeCurrencies = getC2LManager().getActiveCurrencies();
		if (activeCurrencies.isEmpty())
		{
			throw new JaloSystemException(null, "No active currency found for new session of user " + newUser.getLogin()
					+ ". Check restrictions.", 0);
		}
		if (!currentCurrency.isAlive() || !activeCurrencies.contains(currentCurrency))
		{
			final Currency newCurr = (Currency) activeCurrencies.iterator().next();
			log.info("transfering session to user " + newUser.getLogin() + ": forced to switch currency to " + newCurr.getIsoCode());
			getSessionContext().setCurrency(newCurr);
		}
		setLoginProperties(props);
	}