SAX problem(plz see the code given)

Question

hi all,
i am using SAX parser for validating my xml file against the dtd,i am getting some errors that i am not able to make out.cud u plz help me.i am sending u my files.
------------------------java file------------------------------------
import java.io.*;
import org.xml.sax.*;
import org.xml.sax.helpers.DefaultHandler;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
public class Echo extends DefaultHandler
public static void main(String argv[]){
if (argv.length != 1) {
System.err.println("Usage: cmd filename");
System.exit(1);
// Use an instance of ourselves as the SAX event handler
//DefaultHandler handler=new DefaultHandler();
Echo handler=new Echo();
// Use the default (non-validating) parser
SAXParserFactory factory = SAXParserFactory.newInstance();
factory.setValidating(true);
try {
// Set up output stream
out = new OutputStreamWriter(System.out, "UTF8");
// Parse the input
SAXParser saxParser = factory.newSAXParser();
saxParser.parse( new File(argv[0]), handler );
catch (SAXParseException spe) {
// Error generated by the parser
System.out.println("\n** Parsing error"
+ ", line " + spe.getLineNumber()
+ ", uri " + spe.getSystemId());
System.out.println(" " + spe.getMessage() );
}catch (Throwable t){
t.printStackTrace();
System.exit(0);
static private Writer out;
public void startDocument()
throws SAXException{
emit("<?xml version='1.0' encoding='UTF-8'?>");
nl();
public void endDocument()
throws SAXException{
try {
nl();
out.flush();
}catch (IOException e) {
throw new SAXException("I/O error", e);
public void startElement(String namespaceURI,
String sName, // simple name (localName)
String qName, // qualified name
Attributes attrs)
throws SAXException
String eName = sName; // element name
if ("".equals(eName)) eName = qName; // namespaceAware = false
emit("<"+eName);
if (attrs != null) {
for (int i = 0; i < attrs.getLength(); i++) {
String aName = attrs.getLocalName(i); // Attr name
if ("".equals(aName)) aName = attrs.getQName(i);
emit(" ");
emit(aName+"=\""+attrs.getValue(i)+"\"");
emit(">");
public void endElement(String namespaceURI,
String sName, // simple name
String qName // qualified name
throws SAXException
emit("</"+qName+">");
public void characters(char buf[], int offset, int len)
throws SAXException
String s = new String(buf, offset, len);
emit(s);
public void ignorableWhitespace(char buf[], int offset, int Len)
throws SAXException
nl();
//emit("IGNORABLE");
private void emit(String s)
throws SAXException
try {
out.write(s);
out.flush();
} catch (IOException e) {
throw new SAXException("I/O error", e);
private void nl()
throws SAXException
String lineEnd = System.getProperty("line.separator");
try {
out.write(lineEnd);
} catch (IOException e) {
throw new SAXException("I/O error", e);
public void error(SAXParseException e)
throws SAXParseException
throw e;
public void warning(SAXParseException e)throws SAXParseException{
System.out.println("WARNING : Line Number:- "+e.getLineNumber());
System.out.println("WARNING : Column Number:- "+e.getColumnNumber());
System.out.println("WARNING : System ID:- "+e.getSystemId());
System.out.println("WARNING : Public Number:- "+e.getPublicId());
--------------------------xml file------------------------------------
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE slideshow SYSTEM "echo.dtd">
<!-- A SAMPLE set of slides -->
<slideshow
title="Sample Slide Show"
date="Date of publication"
author="Yours Truly"
>
<![CDATA[Digram : frobmorten <------------ fuznaten
| <3> ^
| <1> | <1> = fozzle
V | <2> = framboze
Staten+ <3> = frenzle
<2>
]]>
<!-- TITLE SLIDE -->
<slide type="all">
<image src="my.gif" alt="this is my pic" type="image/gif"/>
<title>Wake up to WonderWidgets!</title>
</slide>
<!-- OVERVIEW -->
<slide type="all">
<title>Overview</title>
<item>WonderWidgets are great</item>
<item/>
<item>Who buys WonderWidgets</item>
</slide>
<slide type="all">
<title>Overview</title>
<item>Who buys WonderWidgets</item>
</slide>
</slideshow>
-----------------------------dtd file---------------------------------
<!ELEMENT slideshow (slide+)>
<!ATTLIST slideshow
title CDATA #IMPLIED
date CDATA #IMPLIED
author CDATA #IMPLIED
>
<!ELEMENT slide (image?,title, item*)>
<!ATTLIST slide type CDATA #IMPLIED>
<!ELEMENT title (#PCDATA)>
<!ELEMENT item (#PCDATA | item)* >
<!ELEMENT image EMPTY>
<!ATTLIST image
alt CDATA #IMPLIED
src CDATA #REQUIRED
type CDATA "image/gif"
>
-----------------------ERROR I AM GETTING IS--------------------------
<?xml version='1.0' encoding='UTF-8'?>
<slideshow title="Sample Slide Show" date="Date of publication" author="Yours Tr
uly">
Digram : frobmorten <------------ fuznaten
| <3> ^
| <1> | <1> = fozzle
V | <2> = framboze
Staten+ <3> = frenzle
<2>
<slide type="all">
<image src="my.gif" alt="this is my pic" type="image/gif"></image>
<title>Wake up to WonderWidgets!</title>
</slide>
<slide type="all">
<title>Overview</title>
<item>WonderWidgets are great</item>
<item></item>
<item>Who buys WonderWidgets</item>
</slide>
<slide type="all">
<title>Overview</title>
<item>Who buys WonderWidgets</item>
</slide>
org.xml.sax.SAXException: The content of element type "slideshow" must m
atch "(slide)+".
at org.apache.xerces.parsers.AbstractSAXParser.parse(AbstractSAXParser.j
ava:979)
at javax.xml.parsers.SAXParser.parse(Unknown Source)
at javax.xml.parsers.SAXParser.parse(Unknown Source)
at Echo.main(Echo.java:28)
with my lot efforts i am not able to make out where i am wrong,plz do have a look on the codes.
thanx in advance
best regards
anshul

Answer 1

Hi i have consulted the XML spec and it is not possible to have a CDATA section as element content. A element declaration can have only content that is empty, ANY (i.e. can include any other declared elements in DTD), mixed (i.e. can contain PCDATA or child elements, or child elements. An element cannot include any character data which CDATA represents. i.e it is not valid to do <!ELEMENT slideshow CDATA>
The CDATA can only be used with an attribute declaration. Regard CDATA as a type definition for any attribute variables.
So what do i suggest. You could declare a separate element which has an attribute for the CDATA section
<!ELEMENT input (Name)>
<!ATTLIST input instructions CDATA #REQUIRED>
hope this helps.