Java XPath Create getXpathVal(InputStream pInputStream, String pXPath)

Description

Recover the value associated with a xpath expression

License

Apache License

Parameter

Parameter	Description
pInputStream	xml file
pXPath	XPath expression to evaluate

Return

value value associated with the xpath expression (or null if error)

Declaration

public static String getXpathVal(InputStream pInputStream, String pXPath) 

Method Source Code

//package com.java2s;
/*//  ww  w .j a va 2  s  . co m
 * Copyright 2014 The British Library/SCAPE Project Consortium
 * Author: William Palmer (William.Palmer@bl.uk)
 *
 *   Licensed under the Apache License, Version 2.0 (the "License");
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 */

import java.io.IOException;
import java.io.InputStream;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;

import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.xml.sax.SAXException;

public class Main {
    /**
     * Recover the value associated with a xpath expression
     * @param pInputStream xml file
     * @param pXPath XPath expression to evaluate
     * @return value value associated with the xpath expression (or null if error)
     */
    public static String getXpathVal(InputStream pInputStream, String pXPath) {
        try {
            DocumentBuilder docB = DocumentBuilderFactory.newInstance().newDocumentBuilder();
            Document doc = docB.parse(pInputStream);
            Node root = doc.getFirstChild();
            XPath xpath = XPathFactory.newInstance().newXPath();
            return xpath.evaluate(pXPath, root);
        } catch (ParserConfigurationException pce) {
        } catch (NumberFormatException e) {
        } catch (XPathExpressionException e) {
        } catch (SAXException e) {
        } catch (IOException e) {
        }
        return null;
    }
}

Related

1. getXPathNoCache(String exp)
2. getXPathNodeIndex(Node node, boolean ignoreWhitespace)
3. getXPathNodes(XPath xpath, Object inic, String name)
4. getXPathToContent(final Node root, final String selectedContent)
5. getXPathType(Class c)
6. getXPathValue(XPath xpath, Node d, String xq, String def)
7. newXPath()
8. newXPath()
9. newXpathExpression(final XPath xpath, final String expression)