XML Parsing (newbie) confused

Question

I am trying parse an xml file and look for a particualr part. But I can't seem to get the output to look correct. I have attached my code and output below as well as the xml and dtd files.
What I want to do is take the partnumber if it exists in my xml file and then show the url link... when I do my normal jdbc query.
import java.io.IOException;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Text;
import org.xml.sax.SAXException;
public class XMLParser {
    public static void main(String[] args) {
        Document doc = parseXmlFile("c:/monarch.xml", false);
          NodeList nodelist = doc.getElementsByTagName("part");
          System.out.println("nodelist size is " + nodelist.getLength());
          // got the nodelist of "part"
          for(int a=0; a<nodelist.getLength(); a++) {
               Node node = nodelist.item(a);                                                  // this is the "part"
               // loop through the childs
               NodeList nodelist2 = node.getChildNodes();
               for(int b=0; b<nodelist2.getLength(); b++) {                              // child length is "4" correct
                   Node node2 = nodelist2.item(b);
                    System.out.println("Nodename is " + node2.getNodeName());
                    System.out.println("Nodename is " + node2.getNodeValue());
    public static Document parseXmlFile(String filename, boolean validating) {
        try {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            factory.setValidating(validating);
            Document doc = factory.newDocumentBuilder().parse(new File(filename));
            return doc;
        } catch (SAXException e) {
            e.getMessage();
        } catch (ParserConfigurationException e) {
             e.getMessage();
        } catch (IOException e) {
             e.getMessage();
        return null;
}Output:
nodelist size is 2
Nodename is #text
Nodename is
Nodename is partnumber
Nodename is null
Nodename is #text
Nodename is
Nodename is sku
Nodename is null
Nodename is #text
Nodename is
Nodename is cost
Nodename is null
Nodename is #text
Nodename is
Nodename is link
Nodename is null
Nodename is #text
Nodename is
Nodename is #text
Nodename is
Nodename is partnumber
Nodename is null
Nodename is #text
Nodename is
Nodename is sku
Nodename is null
Nodename is #text
Nodename is
Nodename is cost
Nodename is null
Nodename is #text
Nodename is
Nodename is link
Nodename is null
Nodename is #text
Nodename is
My XML File:
<?xml version="1.0" encoding="ISO-8859-1"?><!DOCTYPE catalog SYSTEM "file:///c:/monarch.dtd">
<catalog>
     <part>
          <partnumber>xyz</partnumber>
          <sku>450252</sku>
          <cost>37.25</cost>
          <link>http://www.test.com/</link>
     </part>
     <part>
         <partnumber>abc</partnumber>
          <sku>220251</sku>
          <cost>18.50</cost>
          <link>http://www.test.com/</link>
     </part>
</catalog>
[\code]
and DTD<?xml encoding="UTF-8"?>
<!ELEMENT catalog (part)+>
<!ATTLIST catalog
xmlns CDATA #FIXED ''>
<!ELEMENT part (partnumber,sku,cost,link)>
<!ATTLIST part
xmlns CDATA #FIXED ''>
<!ELEMENT partnumber (#PCDATA)>
<!ATTLIST partnumber
xmlns CDATA #FIXED ''>
<!ELEMENT sku (#PCDATA)>
<!ATTLIST sku
xmlns CDATA #FIXED ''>
<!ELEMENT cost (#PCDATA)>
<!ATTLIST cost
xmlns CDATA #FIXED ''>
<!ELEMENT link (#PCDATA)>
<!ATTLIST link
xmlns CDATA #FIXED ''>
How can I get it so that I can loop through the list and when I come to say part abc... I can do something with those 4 entries?
Thanks for any help.

Answer 1

BTW I noticed that your error handling in parseXmlFile probably doesn't do what you want / expect it to. Fixed in the code in this post.
There is an alternative to iterating through the children manually, and that's to use XPath. import java.io.*;
import java.util.*;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.*;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
public class XMLParser {
    public static void main(String[] args) {
        Map<String, String> urlByPartNo = new HashMap<String, String>();
        XPath xpath = XPathFactory.newInstance().newXPath();
        Document doc = parseXmlFile("monarch.xml", false);
        NodeList nodelist = doc.getElementsByTagName("part");
        try
            for (Node partNode : wrap(nodelist))
                String partNo = xpath.evaluate("partnumber/text()", partNode);
                String url = xpath.evaluate("link/text()", partNode);
                if (partNo != null && url != null)
                    urlByPartNo.put(partNo, url);
        catch (XPathException xpe)
            System.out.println(xpe);
        System.out.println("Read following map: " + urlByPartNo);
    public static Document parseXmlFile(String filename, boolean validating) {
        try {
            DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
            factory.setValidating(validating);
            Document doc = factory.newDocumentBuilder().parse(new File(filename));
            return doc;
        } catch (SAXException e) {
            System.err.println(e.getMessage());
        } catch (ParserConfigurationException e) {
            System.err.println(e.getMessage());
        } catch (IOException e) {
            System.err.println(e.getMessage());
        return null;
     * Helper method to all foreach to be applied to <code>NodeList</code>s.
     * @param list A nodelist over which we'd like to iterate.
     * @return An <code>Iterable</code> which can plug straight into a foreach.
    private static Iterable<Node> wrap(final NodeList list)
        return new Iterable<Node>()
                // javadoc inherited.
                public Iterator<Node> iterator()
                    return new Iterator<Node>()
                         * The current index - i.e. that which will be accessed
                         * by the next call to {@link #next()}.
                        private int curr = 0;
                         * The length of the nodelist.
                        private int length = list.getLength();
                        // javadoc inherited
                        public boolean hasNext()
                            return curr < length;
                        // javadoc inherited
                        public Node next()
                            return list.item(curr++);
                        // javadoc inherited
                        public void remove()
                            // There's no way to support removal, even if I
                            // wanted to.
                            throw new UnsupportedOperationException();
}