Java XPath Get getFirstByXPath(Object obj, String xpathExpression)

Description

Get the first node from the specified object using the specified XPath expression.

License

Open Source License

Parameter

Parameter	Description
obj	the object
xpathExpression	the XPath expression

Return

the first node from the specified object matched using the specified XPath expression

Declaration

public static Node getFirstByXPath(Object obj, String xpathExpression) 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * Copyright (c) 2010-2012 by Min Cai (min.cai.china@gmail.com).
 *
 * This file is part of the PickaPack library.
 *
 * PickaPack is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version./* w  ww.  ja v  a 2s. c  o m*/
 *
 * PickaPack 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with PickaPack. If not, see <http://www.gnu.org/licenses/>.
 ******************************************************************************/

import org.w3c.dom.Node;

import javax.xml.namespace.QName;

import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;

public class Main {
    private static XPath xpath = XPathFactory.newInstance().newXPath();

    /**
     * Get the first node from the specified object using the specified XPath expression.
     *
     * @param obj the object
     * @param xpathExpression the XPath expression
     * @return the first node from the specified object matched using the specified XPath expression
     */
    public static Node getFirstByXPath(Object obj, String xpathExpression) {
        return evaluate(obj, xpathExpression, XPathConstants.NODE);
    }

    @SuppressWarnings("unchecked")
    private static <T> T evaluate(Object obj, String xpathExpression, QName qName) {
        try {
            return (T) xpath.compile(xpathExpression).evaluate(obj, qName);
        } catch (XPathExpressionException e) {
            throw new RuntimeException(e);
        }
    }
}

Related

1. getElementsByXPath(Element parent, String name)
2. getElementXPath(Node elt)
3. getExcelPath()
4. getFactory()
5. getFastXPath(Node node)
6. getFullXPath(Node n)
7. getHtmlXPath()
8. getInt(Object node, XPathExpression expression)
9. getLatestVersion(String tempDir, String url, String groupId, String artifactId, String version)