XPath tester

import org.w3c.dom.Document;
import org.w3c.dom.NodeList;

import org.xml.sax.InputSource;

import java.io.FileInputStream;
import java.io.InputStream;

import java.net.MalformedURLException;
import java.net.URL;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathFactory;


/**
 * Process an xml source, applying an XPath pattern to it, printing the affected
 * nodes
 *
 * @author CEHJ
 * @created 28 April 2004
 */
public class XPathTest {
    public static void main(String[] args) {
        try {
            if (args.length < 2) {
                System.out.println(
                    "Usage: java XPathTest <URL> <XPath pattern>");
                System.exit(-1);
            }

            process(args);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * Process a document against a Pattern
     */
    public static void process(String[] args) throws Exception {
        if (args.length < 2) {
            System.out.println();
            System.exit(1);
        }
        int numNodes = 0;
        NodeList nodeList = XPathTest.process(args[0], args[1]);
        if (nodeList != null && (numNodes = nodeList.getLength()) > 0) {
            for (int i = 0; i < numNodes; i++) {
                System.out.println(nodeList.item(i));
            }
        } else {
            System.out.println("Nothing found.");
        }
    }

    /**
     * Process a document against a Pattern
     */
    public static NodeList process(String inputSourcePath, String pattern)
        throws Exception {
        NodeList result = null;
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setValidating(false);
        factory.setIgnoringElementContentWhitespace(true);

        DocumentBuilder builder = factory.newDocumentBuilder();

        // Create document from URL - if it's not a url, try a file
        InputStream in = null;

        try {
            URL url = new URL(inputSourcePath);
            in = url.openStream();
        } catch (MalformedURLException e) {
            in = new FileInputStream(inputSourcePath);
        }

        Document document = builder.parse(new InputSource(in));
        document.getDocumentElement().normalize();

        XPath xpath = XPathFactory.newInstance().newXPath();

        /*
         * If namespaces being used NamespaceContextImpl nsctx = new
         * NamespaceContextImpl(); nsctx.setNamespaceURI("xhtml",
         * "http://www.w3.org/1999/xhtml"); xpath.setNamespaceContext(nsctx);
         */

        // Evaluate the document against the pattern
        NodeList nodeList = (NodeList) xpath.evaluate(pattern, document,
                XPathConstants.NODESET);

        if (nodeList.getLength() > 0) {
            result = nodeList;
        }

        return result;
    }
}