Question about XML DOM de-bugging.

Question

I have programmed the following class as an excercise in using the DOM and in recursion.
I'm having trouble,however, in debugging my iterate() method.
Sometimes it fails to print certain outer tags.
I'm faily confident there aren't any problems in using entirely static methods in the class.
I simply want it to iterate over all Nodes in the xml document,
and print them to the file in correct order.
Is there anyone out there who could debug my iterate() method?
import org.w3c.dom.*;
import javax.xml.parsers.*;
import java.io.*;
public class DomParsing {
private static PrintStream stream;
public static void main (String [] args)
try
DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = builderFactory.newDocumentBuilder();
File file = new File("cd-catalog.xml");
Node child = null;
Document document = builder.parse(file);
Node element = (Node)document.getDocumentElement();
stream = new PrintStream(new File("SCREEN_OUTPUT.txt"));
iterate(element);
stream.close();
catch (Exception e)
{e.printStackTrace();}
public static void iterate(Node element) //bug in this method.
if(element instanceof Node)
peekNode(element);
peekAttributes(element);
Node [] children = getChildren(element);
if(children instanceof Node[])
for(int i=0;i<children.length;i++)
iterate(children);
element = getSibling(element);
if(element instanceof Node)
iterate(element);
else {
return;}
private static Node [] getChildren(Node element)
Node [] children = null;
if(element.hasChildNodes()){
NodeList nodes= element.getChildNodes();
children = new Node [nodes.getLength()];
for(int i=0;i<nodes.getLength();i++)
{children[i] = nodes.item(i);}
return children;}
private static Node getSibling(Node element)
return element.getNextSibling();}
private static void peekNode(Node node)
if((node instanceof Node) && (stream instanceof PrintStream))
if(node.getNodeName()!=null && (!node.getNodeName().equals("#text")))
{stream.println(new String(node.getNodeName()));
if(node.getNodeValue()!=null)
{stream.println(new String(node.getNodeValue()));
private static void peekAttributes(Node element)
if(element.hasAttributes())
NamedNodeMap map = element.getAttributes();
for(int i=0;i<map.getLength();i++)
Attr attribute = (Attr)map.item(i);
peekNode((Node)attribute);}

Answer 1

Never fear, Ihave found my answer!
I had unwitingly disasociated recursive steps,
instead of correctly associated.
The following runs correctly in
all my instances:
   import org.w3c.dom.*;
   import javax.xml.parsers.*;
   import java.io.*;
   import java.util.*;
    public class DomParsing {
    //Main method call to leverage the Iterator Class.
       public static void main (String [] args)
         Iterator iterator = new Iterator("tomcat-users.xml");
    class Iterator {
      private LinkedList<String> myDocument;
      //private  PrintStream stream; 
        //Constructor accesses xml file for parsing work.
       public Iterator (String fileName)
         try{
            DocumentBuilderFactory builderFactory = DocumentBuilderFactory.newInstance();
            DocumentBuilder builder = builderFactory.newDocumentBuilder();
            File file = new File(fileName);
            Node child = null;
            Document document = builder.parse(file);
            Node element = (Node)document.getDocumentElement();
            //stream = new PrintStream(new File("SCREEN_OUTPUT.txt"));
            myDocument = new LinkedList<String>();
            System.out.println("___________________________________________________");
            iterate(element);  
           //stream.close();               
            ListIterator<String> nodes = myDocument.listIterator();
            while(nodes.hasNext())
               System.out.println(nodes.next().trim());
            System.out.println("___________________________________________________");
             catch (Exception e)
            {e.printStackTrace();}
      //This method is intended to be called recursively
        //to set up a "tree" arrangement in memory
        //representing an xml document tree.
       private void iterate(Node element)       {
         if (element == null)
            return;
         if(element instanceof Node)
            peekNode(element);
            peekAttributes(element);
            Node [] children = getChildren(element);
            if(children instanceof Node[])
               for(int i=0;i<children.length;i++)
                  iterate(children);
Node sibling = getSibling(element);
if(sibling instanceof Node)
{iterate(sibling);}
//Returns array of all Children Nodes of an Element.
private Node [] getChildren(Node element)
Node [] children = null;
if(element.hasChildNodes()){
NodeList nodes= element.getChildNodes();
children = new Node [nodes.getLength()];
for(int i=0;i<nodes.getLength();i++)
{children[i] = nodes.item(i);}
return children;}
//Obtains the next Sibling element
private Node getSibling(Node element)
return element.getNextSibling();}
     //These print any Node and any data,
     //from Element,attribute,attribute values,
     //sibling,child, etc..
private void peekNode(Node node)
if((node instanceof Node))// && (stream instanceof PrintStream))
if(node.getNodeName()!=null && (!node.getNodeName().equals("#text")))
{//stream.println(new String(node.getNodeName().trim()));
myDocument.add(node.getNodeName().trim());
//System.out.println(node.getNodeName().toString());
if(node.getNodeValue()!=null)
{//stream.println(new String(node.getNodeValue().trim()));
myDocument.add(node.getNodeValue().trim());
//System.out.println(node.getNodeValue().toString());
     //This examines the xml attributes on and element node.
private void peekAttributes(Node element)
if(element.hasAttributes())
NamedNodeMap map = element.getAttributes();
for(int i=0;i<map.getLength();i++)
Attr attribute = (Attr)map.item(i);
peekNode((Node)attribute);}