Xerces-J Parse throws NoSuchElementException

[Barry Adams <ba...@magus.co.uk>]

  When using Xerces 1.2.1 (and also previously 1.0.4) as a non Validating
parser, i get a java.util.NoSuchElementException when it tries to read an
attribute, any idea why, I'm I calling it somehow wrong and if so why isn't
it throwing  a SAXException?

Example input:
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
"http://www.wapforum.org/DTD
/wml_1.1.xml">
 
<wml>
<card title="fieldScores=3,title:1"> 
   -- Error Thrown Here before rest of file read

Sax Invoked by

import java.io.*;
import java.util.*;
import org.xml.sax.helpers.*;
import org.xml.sax.*;
import org.apache.xerces.parsers.SAXParser;

public class XMLSaxHandler extends org.xml.sax.helpers.DefaultHandler {

  public static String SAXParserName = "org.apache.xerces.parsers.SAXParser";

  XMLCallBack whoToCall;
  public StringBuffer content;
  private Vector activeElements;

  public XMLSaxHandler(XMLCallBack xcb) {
    super();
    whoToCall = xcb;
    content = new StringBuffer();
    activeElements = new Vector();
  }

  private void reset(){
    content = new StringBuffer();
    activeElements = new Vector();
  }

  public void readXML(InputStream byteStream) throws IOException {
    reset();
    try {
      XMLReader xr = XMLReaderFactory.createXMLReader(SAXParserName);
      xr.setContentHandler(this);
      xr.setErrorHandler(this);
      InputSource is = new InputSource(byteStream);
      if (whoToCall instanceof Parser){
        Parser p = (Parser) whoToCall;
        is.setEncoding(p.characterEncoding);
      }
      try {
        xr.setFeature("http://xml.org/sax/features/validation", false);
      } catch (org.xml.sax.SAXException e) {
        System.out.println("error in setting up parser feature");
      }
      xr.parse(is);
    } catch (org.xml.sax.SAXException e){
      e.printStackTrace();
      throw new IOException("SAX Exception "+e);
    }
  }
  public void characters(char c[], int start,int len){
    System.err.println("- "+new String(c,start,len));
    content.append(c,start,len);
  }

  public void ignorableWhitespace(){
    content.append(" ");
  }

  public void endDocument(){
    send();
  }


  public void startElement(String nameURI,String localname,String qname,
Attributes att){
    if (content.length()!=0){send();}
    String name = localname;
    System.err.println("<"+nameURI+" "+localname+" "+qname+">");
    if (name.equals("")){
      name = qname;
    }
    XMLAttributeContext xac = new XMLAttributeContext();
    activeElements.add(name);
    for(int i=0;i<att.getLength();i++){
      String aname = att.getLocalName(i);
      if (aname.equals("")){
        aname = att.getQName(i);
      }
      String value = att.getValue(i);
      if (!value.equals("")){
        whoToCall.attCallBackPass1(name+"!"+aname,value,xac);
      }
    }
    for(int i=0;i<att.getLength();i++){
      String aname = att.getLocalName(i);
      if (aname.equals("")){
        aname = att.getQName(i);
      }
      String value = att.getValue(i);
      if (!value.equals("")){
        whoToCall.attCallBackPass2(name+"!"+aname,value,xac);
      }
    }
  }

  public void endElement(String nameURI,String localname,String qname){
    if (content.length()!=0){send();}
    String name = localname;
    if (name.equals("")){
      name = qname;
    }
    activeElements.remove(name);
  }

  private void send(){
    StringBuffer whatisit = new StringBuffer();
    for(Enumeration e=activeElements.elements();e.hasMoreElements();){
      String name = (String) e.nextElement();
      whatisit.append("!");
      whatisit.append(name);
    }
    whoToCall.callBack(whatisit.toString(),content.toString());
    content.setLength(0);
  }

}

Stack Trace was

java.util.NoSuchElementException
        at org.apache.xerces.framework.XMLParser.parse(XMLParser.java:917)
        at MyApp.XMLSaxHandler.readXML(XMLSaxHandler.java:41)

Changing the XML file, and checking output from StartElement and characters
output calls reveals the error occurs while reading an element with an
attribute.

Barry Adams
badams@magus.co.uk