if (logger.isInfoEnabled()) {
            logger.info("[EXEC TIME] crawling time: {}ms", execTime);
        }

        indexUpdater.setFinishCrawling(true);
        try {
            indexUpdater.join();
        } catch (final InterruptedException e) {
            logger.warn("Interrupted index update.", e);
        }

        return sessionIdList;
    }

    public void setSessionIdList(final List<String> sessionIdList) {
        this.sessionIdList = sessionIdList;
    }

    public void setFinishCrawling(final boolean finishCrawling) {
        this.finishCrawling = finishCrawling;
    }

    public long getDocumentSize() {
        return documentSize;
    }

    @Override