Java XPath Select xpathOrNull(Document doc, String xp)

Description

Evaluate an XPath against a Document, returning a String.

License

Open Source License

Parameter

Parameter	Description
doc	Document
xp	XPath to evaluate against Document

Return

String found at path or null

Declaration

public static String xpathOrNull(Document doc, String xp) 

Method Source Code

//package com.java2s;
/* XmlUtils/*ww w .  j  ava 2s. c  o  m*/
 *
 * Created on Sep 19, 2007
 *
 * Copyright (C) 2007 Internet Archive.
 *
 * This file is part of the Heritrix web crawler (crawler.archive.org).
 *
 * Heritrix is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser Public License as published by
 * the Free Software Foundation; either version 2.1 of the License, or
 * any later version.
 *
 * Heritrix is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser Public License for more details.
 *
 * You should have received a copy of the GNU Lesser Public License
 * along with Heritrix; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Document;

public class Main {
    /**
     * Evaluate an XPath against a Document, returning a String.
     * 
     * @param doc Document
     * @param xp XPath to evaluate against Document
     * @return String found at path or null
     */
    public static String xpathOrNull(Document doc, String xp) {
        XPathFactory factory = XPathFactory.newInstance();
        XPath xpath = factory.newXPath();
        try {
            XPathExpression expr = xpath.compile(xp);
            return expr.evaluate(doc);
        } catch (XPathExpressionException e) {
            return null;
        }
    }
}

Related

1. selectXPathString(final String xPath, final Node inNode, final String nsuri, final String pre)
2. xmlSelectNodes(Node node, String xpathExpression)
3. XPathAPI_selectNodeList(Document doc, String xpath, Node namespaceNode)
4. xpathNode(String expr, Document doc)
5. xpathNodeList(String expr, Document doc)
6. xpathString(String expr, Document doc)
7. xpathToNode(Document document, String xpathExpression)