Weblogs with DOM

import org.w3c.dom.*;
import org.w3c.dom.traversal.*;
import org.xml.sax.SAXException;
import java.io.IOException;
import java.util.*;
import java.net.*;


public class WeblogsDOM {

  public static String DEFAULT_URL 
   = "http://static.userland.com/weblogMonitor/logs.xml"; 
     
  public static List listChannels() throws DOMException {
    return listChannels(DEFAULT_URL); 
  }
  
  public static List listChannels(String uri) throws DOMException {
    
    if (uri == null) {
      throw new NullPointerException("URL must be non-null");   
    }

    org.apache.xerces.parsers.DOMParser parser 
     = new org.apache.xerces.parsers.DOMParser();
    
    Vector urls = null;
    
    try {
      // Read the entire document into memory
      parser.parse(uri); 
      Document doc = parser.getDocument();
      org.apache.xerces.dom.DocumentImpl impl 
       = (org.apache.xerces.dom.DocumentImpl) doc;
      NodeIterator iterator = impl.createNodeIterator(doc, 
       NodeFilter.SHOW_ALL, new URLFilter(), true);
      urls = new Vector(100);

      Node current = null;
      while ((current = iterator.nextNode()) != null) {
        try {
          String content = current.getNodeValue();
          URL u = new URL(content);
          urls.addElement(u);
        }
        catch (MalformedURLException e) {
          // bad input data from one third party; just ignore it 
        }
      }
    }
    catch (SAXException e) {
      System.err.println(e); 
    }
    catch (IOException e) {
      System.err.println(e); 
    }
    
    return urls;
    
  }
  
  static class URLFilter implements NodeFilter {
        
    public short acceptNode(Node n) {
      
      if (n instanceof Text) {
        Node parent = n.getParentNode();
        if (parent instanceof Element) {
          Element e = (Element) parent;
          if (e.getTagName().equals("url")) {
            return NodeFilter.FILTER_ACCEPT;       
          }
        }
      }
      
      return NodeFilter.FILTER_REJECT;
      
    }
    
  }
    
  public static void main(String[] args) {
     
    try {
      List urls;
      if (args.length > 0) {
        try {
          URL url = new URL(args[0]);
          urls = listChannels(args[0]);
        }
        catch (MalformedURLException e) {
          System.err.println("Usage: java WeblogsJDOM url");
          return;
        }
      }
      else {
        urls = listChannels();
      }
      Iterator iterator = urls.iterator();
      while (iterator.hasNext()) {
        System.out.println(iterator.next()); 
      }
    }
    catch (/* Unexpected */ Exception e) {
      e.printStackTrace(); 
    }
    
  } // end main

}