if (StringUtil.isBlank(responseContentType)) {
                    response.setHeader("Content-Type", "application/json");
                } else {
                    response.setHeader("Content-Type", responseContentType);
                }
                CopyUtil.copy(in, out);
            } catch (final ClientAbortException e) {

    /**
     * Return the comment header.
     *
     * @return the comment header
     */
    public List<String> getHeader() {
        return header;
    }

    /**
     * Set the comment header.
     *
     * @param header the header to use
     */
    public void setHeader(List<String> header) {
        this.header = header;
    }

    /**
     * Return the comment footer.
     *

        }
        final SearchHelper searchHelper = ComponentUtil.getSearchHelper();
        final FessConfig fessConfig = ComponentUtil.getFessConfig();

        if (!fessConfig.isAcceptedSearchReferer(request.getHeader("referer"))) {
            writeJsonResponse(HttpServletResponse.SC_BAD_REQUEST, escapeJsonKeyValue(MESSAGE_FIELD, "Referer is invalid."));
            return;
        }

        if (!fessConfig.isApiSearchScroll()) {

    @Nullable
    Path getPath();

    @Nullable
    Path getRootDirectory();

    @Nullable
    URL getURL();

    @Nullable
    InputStream getInputStream();

    @Nullable
    Reader getReader();

    @Nullable
    Transformer getTransformer();

    boolean isStrict();

    @Nullable
    String getModelId();

    @Nullable
    String getLocation();

            searchLog.setClientIp(StringUtils.abbreviate(ComponentUtil.getViewHelper().getClientIp(req), 100));
            searchLog.setReferer(StringUtils.abbreviate(req.getHeader("referer"), 1000));
            searchLog.setUserAgent(StringUtils.abbreviate(req.getHeader("user-agent"), 255));
            final Object accessType = req.getAttribute(Constants.SEARCH_LOG_ACCESS_TYPE);

        nonNull(request, "request");
        Path path = request.getPath();
        URL url = request.getURL();
        Reader reader = request.getReader();
        InputStream inputStream = request.getInputStream();
        if (path == null && url == null && reader == null && inputStream == null) {

                    logger.debug("principal: {}", principal);
                }
            } catch (final Exception e) {
                final String msg = "Failed to process Authorization Header: " + request.getHeader(Constants.AUTHZ_HEADER);
                if (logger.isDebugEnabled()) {
                    logger.debug(msg);
                }
                throw new SsoLoginException(e.getMessage() + " " + msg, e);
            }

        }

    }

    protected void processHeader(final HttpServletRequest request, final Set<String> roleSet) {

        final String parameter = request.getHeader(headerKey);
        if (logger.isDebugEnabled()) {
            logger.debug("{}:{}", headerKey, parameter);
        }
        if (StringUtil.isNotEmpty(parameter)) {

                return;
            }
        }
        response.contentType(mimeType);
    }

    public String getClientIp(final HttpServletRequest request) {
        final String value = request.getHeader("x-forwarded-for");
        if (StringUtil.isNotBlank(value)) {
            return value;
        }
        return request.getRemoteAddr();
    }