} catch (final Exception e) {
                logger.warn("Failed to restore " + urlQueue, e);
            }
        }));
    }

    /**
     * Clears the cache.
     */
    public void clearCache() {
        sessionCache.clear();
    }

    /**
     * Updates the session ID for all URL queue entries.
     *
     * @param oldSessionId The old session ID.