XPath Sample

XPathSample.java

import java.io.IOException;
import java.io.StringReader;

import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;

import org.w3c.dom.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;

public class XPathSample {
	public static void main(String[] args) throws Exception {
		String xmlString = createXMLString();
		Document document = documentWithXMLString(xmlString);
		
		String xpathString = "//company/url/text()";
		NodeList nlist = nodeWithXPath(xpathString, document);

		for (int i = 0; i < nlist.getLength(); i++) {
			System.out.println("--- " + i + " ---");
			System.out.println(nlist.item(i).getNodeValue());
		}
	}

	public static Document documentWithXMLString(String xmlString)
			throws SAXException, IOException, ParserConfigurationException {
		InputSource is = new InputSource();
		is.setCharacterStream(new StringReader(xmlString));
		Document doc = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(is);
		return doc;
	}

	public static NodeList nodeWithXPath(String xpathString, Document document) throws XPathExpressionException {
		return (NodeList) XPathFactory.newInstance().newXPath().evaluate(xpathString, document, XPathConstants.NODESET);
	}

	public static String createXMLString() {
		StringBuilder sb = new StringBuilder();
		sb.append("<?xml version=\"1.0\" encoding=\"UTF-8\" ?>");
		sb.append("<companies>");
		sb.append("<company>");
		sb.append("<name>example.com</name>");
		sb.append("<url>http://www.example.com/</url>");
		sb.append("</company>");
		sb.append("<company>");
		sb.append("<name>example.jp</name>");
		sb.append("<url>http://www.example.jp/</url>");
		sb.append("</company>");
		sb.append("</companies>");
		return sb.toString();
	}
}