} catch (final UnknownHostException e) {
            throw new FessSystemException("Failed to resolve the hostname: " + host, e);
        }
    }

    @PostConstruct
    public void open() {
        if (logger.isDebugEnabled()) {
            logger.debug("Initialize {}", this.getClass().getSimpleName());
        }
        final FessConfig fessConfig = ComponentUtil.getFessConfig();