/**
	 * Changes the session user without any login processing. Further the session cart is assigned to the new user.
	 *
	 * @param u
	 *           the new user
	 */
	public void setUser(final User u)
	{
		if (u == null)
		{
			throw new JaloInvalidParameterException("session user cannot be null", 0);
		}
		if (!u.equals(getUser()))
		{
			final User previous = u;
			//
			getSessionContext().setUser(u);
			if (hasCart())
			{
				getCart().setUser(u);
			}
			notifyExtensionsAfterUserChange(previous);
		}
	}