for (final Map.Entry<String, List<String>> entry : frontMatter.entrySet()) {
            final String key = "frontmatter." + entry.getKey();
            final List<String> values = entry.getValue();
            if (values != null && !values.isEmpty()) {
                extractData.putValues(key, values.toArray(new String[0]));
            }
        }
    }

    /**

        final StringBuilder buf = new StringBuilder(1000);
        buf.append(getResultDataHeader());
        for (final Map.Entry<String, String> entry : fieldRuleMap.entrySet()) {
            final String path = entry.getValue();
            try {
                final XPathEvaluationResult<?> xObj = getXPathAPI().eval(document, path);
                switch (xObj.type()) {
                case BOOLEAN:

                queryBuf.append(URLUtil.encode(entry.getValue(), Constants.UTF_8));
                queryBuf.append('=');
                queryBuf.append(URLUtil.encode(entry.getKey(), Constants.UTF_8));
                formBuf.append("<input type=\"hidden\" name=\"");
                formBuf.append(StringEscapeUtils.escapeHtml4(entry.getValue()));
                formBuf.append("\" value=\"");

                System.getProperties().entrySet().stream().forEach(e -> logger.debug("Property: {}={}", e.getKey(), e.getValue()));
                System.getenv().entrySet().forEach(e -> logger.debug("Env: {}={}", e.getKey(), e.getValue()));
                logger.debug("Options: options={}", options);
            } catch (final Exception e) {
                // ignore
            }
        }

                            final Map<String, Object> valueCount = new HashMap<>(2, 1f);
                            valueCount.put("value", e.getKey());
                            valueCount.put("count", e.getValue());
                            return valueCount;
                        }).collect(Collectors.toList()));
                        return fieldMap;
                    }).collect(Collectors.toList());

     *
     * @param map the document data as a map of field names to values
     * @return the calculated boost value as a float, or 0.0f if evaluation fails
     */
    public float getValue(final Map<String, Object> map) {
        if (map == null || map.isEmpty()) {
            return 0.0f;
        }

     *
     * @param <T>
     *            the property type
     * @param target
     *            the target object. Must not be {@literal null}
     * @return the property value
     */
    <T> T getValue(Object target);

    /**
     * Sets the value of the property.
     *
     * @param target
     *            the target object. Must not be {@literal null}
     * @param value

            } else if (XHTML_LINK_ELEMENT.equals(elementName)) {
                // Handle hreflang alternate links
                final String rel = attributes.getValue("rel");
                final String hreflang = attributes.getValue("hreflang");
                final String href = attributes.getValue("href");
                if ("alternate".equals(rel) && hreflang != null && href != null) {

            synchronized (urlQueueList) {
                final UrlQueueImpl<Long> urlQueue = new UrlQueueImpl<>();
                final AccessResultImpl<Long> value = entry.getValue();
                urlQueue.setSessionId(sessionId);
                urlQueue.setMethod(value.getMethod());
                urlQueue.setUrl(value.getUrl());
                urlQueue.setParentUrl(value.getParentUrl());

        setupEpg(_epgMap, et -> ((LabelType) et).getUpdatedTime(), (et, vl) -> ((LabelType) et).setUpdatedTime(DfTypeUtil.toLong(vl)),
                "updatedTime");
        setupEpg(_epgMap, et -> ((LabelType) et).getValue(), (et, vl) -> ((LabelType) et).setValue(DfTypeUtil.toString(vl)), "value");
        setupEpg(_epgMap, et -> ((LabelType) et).getVirtualHost(), (et, vl) -> ((LabelType) et).setVirtualHost(DfTypeUtil.toString(vl)),