#fixed code
                                @Override
    public Page download(Request request, Task task) {
        Site site = null;
        if (task != null) {
            site = task.getSite();
        }
        Set<Integer> acceptStatCode;
        String charset = null;
        Map<String, String> headers = null;
        if (site != null) {
            acceptStatCode = site.getAcceptStatCode();
            charset = site.getCharset();
            headers = site.getHeaders();
        } else {
            acceptStatCode = Sets.newHashSet(200);
        }
        logger.info("downloading page {}", request.getUrl());
        CloseableHttpResponse httpResponse = null;
        int statusCode=0;
        try {
            HttpUriRequest httpUriRequest = getHttpUriRequest(request, site, headers);
            httpResponse = getHttpClient(site).execute(httpUriRequest);
            statusCode = httpResponse.getStatusLine().getStatusCode();
            request.putExtra(Request.STATUS_CODE, statusCode);
            if (statusAccept(acceptStatCode, statusCode)) {
                Page page = handleResponse(request, charset, httpResponse, task);
                onSuccess(request);
                return page;
            } else {
                logger.warn("code error " + statusCode + "\t" + request.getUrl());
                return null;
            }
        } catch (IOException e) {
            logger.warn("download page " + request.getUrl() + " error", e);
            if (site.getCycleRetryTimes() > 0) {
                return addToCycleRetry(request, site);
            }
            onError(request);
            return null;
        } finally {
        	request.putExtra(Request.STATUS_CODE, statusCode);
            try {
                if (httpResponse != null) {
                    //ensure the connection is released back to pool
                    EntityUtils.consume(httpResponse.getEntity());
                }
            } catch (IOException e) {
                logger.warn("close response fail", e);
            }
        }
    }
#vulnerable code 
                                @Override
    public Page download(Request request, Task task) {
        Site site = null;
        if (task != null) {
            site = task.getSite();
        }
        Set<Integer> acceptStatCode;
        String charset = null;
        Map<String, String> headers = null;
        if (site != null) {
            acceptStatCode = site.getAcceptStatCode();
            charset = site.getCharset();
            headers = site.getHeaders();
        } else {
            acceptStatCode = Sets.newHashSet(200);
        }
        logger.info("downloading page {}", request.getUrl());
        CloseableHttpResponse httpResponse = null;
        int statusCode=0;
        try {
            HttpUriRequest httpUriRequest = getHttpUriRequest(request, site, headers);
            httpResponse = getHttpClient(site).execute(httpUriRequest);
            statusCode = httpResponse.getStatusLine().getStatusCode();
            request.putExtra(Request.STATUS_CODE, statusCode);
            if (statusAccept(acceptStatCode, statusCode)) {
                Page page = handleResponse(request, charset, httpResponse, task);
                onSuccess(request);
                return page;
            } else {
                logger.warn("code error " + statusCode + "\t" + request.getUrl());
                return null;
            }
        } catch (IOException e) {
            logger.warn("download page " + request.getUrl() + " error", e);
            if (site.getCycleRetryTimes() > 0) {
                return addToCycleRetry(request, site);
            }
            onError(request);
            return null;
        } finally {
        	request.putExtra(Request.STATUS_CODE, statusCode);
            try {
                if (httpResponse != null) {
                    //ensure the connection is released back to pool
                    EntityUtils.consume(httpResponse.getEntity());
                }
            } catch (IOException e) {
                logger.warn("close response fail", e);
            }
            if (site.getHttpProxyPool().isEnable()) {
                site.returnHttpProxyToPool((HttpHost) request.getExtra(Request.PROXY), (Integer) request
                        .getExtra(Request.STATUS_CODE));
            }
        }
    } 
                            #location 51 
                            #vulnerability type THREAD_SAFETY_VIOLATION