import javax.xml.xpath.XPathFactory;
import javax.xml.xpath.XPathNodes;

import org.codelibs.fess.crawler.exception.CrawlerSystemException;
import org.w3c.dom.Node;

public class XPathAPI {

    private final XPath xPath;

    public XPathAPI() {
        xPath = createXPath(f -> {});
    }

    public XPath createXPath(final Consumer<XPathFactory> builder) {
        try {

        }

        return parser;
    }

    protected XPathAPI getXPathAPI() {
        XPathAPI cachedXPathAPI = xpathAPI.get();
        if (cachedXPathAPI == null) {
            cachedXPathAPI = new XPathAPI();
            xpathAPI.set(cachedXPathAPI);
        }
        return cachedXPathAPI;
    }

    protected LoadingCache<String, XPathAPI> xpathAPICache;

    protected long cacheDuration = 10; // min

    @Resource
    public void init() {
        xpathAPICache =
                CacheBuilder.newBuilder().expireAfterAccess(cacheDuration, TimeUnit.MINUTES).build(new CacheLoader<String, XPathAPI>() {
                    @Override
                    public XPathAPI load(final String key) {

            childUrlRuleMap.put(tagName, attrName);
        }
    }

    protected XPathAPI getXPathAPI() {
        XPathAPI cachedXPathAPI = xpathAPI.get();
        if (cachedXPathAPI == null) {
            cachedXPathAPI = new XPathAPI();
            xpathAPI.set(cachedXPathAPI);
        }
        return cachedXPathAPI;
    }

        final XPath xPathApi = getXPathAPI().createXPath(f -> {});
        xPathApi.setNamespaceContext(new DefaultNamespaceContext(doc.getNodeType() == Node.DOCUMENT_NODE ? doc.getDocumentElement() : doc));
        return xPathApi.evaluateExpression(xpath, doc, XPathNodes.class);
    }

    protected XPathAPI getXPathAPI() {
        try {