}
            });

            if (logger.isDebugEnabled()) {
                logger.debug("Terminating process {}.", p);
            }
            try {
                if (!p.destroyForcibly().waitFor(timeout, TimeUnit.MILLISECONDS)) {
                    logger.warn("Terminating process {} is timed out.", p);
                } else if (logger.isDebugEnabled()) {

                        }
                    }
                }

                if (emptyListCount >= maxEmptyListCount) {
                    if (logger.isInfoEnabled()) {
                        logger.info("Terminating indexUpdater. emptyListCount is over {}.", maxEmptyListCount);
                    }
                    // terminate crawling
                    finishCrawling = true;
                    forceStop();