#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;
        try {
            HttpUriRequest httpUriRequest = getHttpUriRequest(request, site, headers);
            httpResponse = getHttpClient(site).execute(httpUriRequest);
            int statusCode = httpResponse.getStatusLine().getStatusCode();
            if (statusAccept(acceptStatCode, statusCode)) {
                //charset
                if (charset == null) {
                    String value = httpResponse.getEntity().getContentType().getValue();
                    charset = UrlUtils.getCharset(value);
                }
                return handleResponse(request, charset, httpResponse, task);
            } 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);
            }
            return null;
        } finally {
            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());
        RequestBuilder requestBuilder = RequestBuilder.get().setUri(request.getUrl());
        if (headers != null) {
            for (Map.Entry<String, String> headerEntry : headers.entrySet()) {
                requestBuilder.addHeader(headerEntry.getKey(), headerEntry.getValue());
            }
        }
        RequestConfig.Builder requestConfigBuilder = RequestConfig.custom()
                .setConnectionRequestTimeout(site.getTimeOut())
                .setSocketTimeout(site.getTimeOut())
                .setConnectTimeout(site.getTimeOut())
                .setCookieSpec(CookieSpecs.BEST_MATCH);
        if (site != null && site.getHttpProxy() != null) {
            requestConfigBuilder.setProxy(site.getHttpProxy());
        }
        requestBuilder.setConfig(requestConfigBuilder.build());
        CloseableHttpResponse httpResponse = null;
        try {
            httpResponse = getHttpClient(site).execute(requestBuilder.build());
            int statusCode = httpResponse.getStatusLine().getStatusCode();
            if (acceptStatCode.contains(statusCode)) {
                //charset
                if (charset == null) {
                    String value = httpResponse.getEntity().getContentType().getValue();
                    charset = UrlUtils.getCharset(value);
                }
                return handleResponse(request, charset, httpResponse, task);
            } 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);
            }
            return null;
        } finally {
            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);
            }
        }
    } 
                            #location 25 
                            #vulnerability type NULL_DEREFERENCE