return sessionId == null ? null : sessionId.toString();
    }

    /**
     * Sets the ID on the target object using reflection.
     *
     * @param target The target object.
     * @param id The ID to set.
     */
    protected void setId(final Object target, final String id) {
        final BeanDesc beanDesc = BeanDescFactory.getBeanDesc(target.getClass());
        final PropertyDesc idProp = beanDesc.getPropertyDesc(ID);

            }
            return;
        }

        if (logger.isInfoEnabled()) {
            logger.info("Checking URL: {}", robotTxtUrl);
        }
        // add url to a set
        crawlerContext.getRobotsTxtUrlSet().add(robotTxtUrl);

        final HttpGet httpGet = new HttpGet(robotTxtUrl);

        // request header
        for (final Header header : requestHeaderList) {