Java tutorial
//package com.java2s; /** * Abiquo community edition * cloud management application for hybrid clouds * Copyright (C) 2008-2010 - Abiquo Holdings S.L. * * This application is free software; you can redistribute it and/or * modify it under the terms of the GNU LESSER GENERAL PUBLIC * LICENSE as published by the Free Software Foundation under * version 3 of the License * * This software 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 GENERAL PUBLIC LICENSE v.3 for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ import java.io.StringReader; import java.util.ArrayList; import java.util.List; import javax.xml.xpath.XPath; import javax.xml.xpath.XPathConstants; import javax.xml.xpath.XPathExpressionException; import javax.xml.xpath.XPathFactory; import org.w3c.dom.NodeList; import org.xml.sax.InputSource; public class Main { /** * Evaluates the XPath expression against the <code>xml</code> and returns the selected values. * * @param expression Expression to evaluate. * @param xml The xml to query. * @return The selected values. * @throws XPathExpressionException If an error occurs evaluating the expression. */ public static List<String> getValues(final String expression, final String xml) throws XPathExpressionException { final NodeList xpathResults = getNodes(expression, xml); final List<String> results = new ArrayList<String>(xpathResults.getLength()); for (int i = 0; i < xpathResults.getLength(); i++) { results.add(xpathResults.item(i).getNodeValue()); } return results; } /** * Evaluates the XPath expression against the <code>xml</code> and returns the selected nodes. * * @param expression Expression to evaluate. * @param xml The xml to query. * @return The selected nodes. * @throws XPathExpressionException If an error occurs evaluating the expression. */ public static NodeList getNodes(final String expression, final String xml) throws XPathExpressionException { final InputSource source = new InputSource(new StringReader(xml)); final XPathFactory factory = XPathFactory.newInstance(); final XPath xpath = factory.newXPath(); return (NodeList) xpath.evaluate(expression, source, XPathConstants.NODESET); } }