Jaxp underlying sax class question

Question

Below is a class that uses the JAXP layer and parses a xml document. All works fine and my results are proper. I would like to use the JAXP abstraction in some code at work, but I am not sure of two things.
1) What underlying parser does this use.? I believe the answser has to do with where the class was downloaded? Crimson from sun, Xerces from Apache. But I am writing code that will go to a remote server.
2) So if the above is true, how can I through code find out what underlying parser it is using, and can I override it somehow on this remote server?
Thanks,
Scott
from java and xml oreilly
package javaxml2;
import java.io.File;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
// JAXP
import javax.xml.parsers.FactoryConfigurationError;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.parsers.SAXParser;
// SAX
import org.xml.sax.AttributeList;
import org.xml.sax.HandlerBase;
import org.xml.sax.SAXException;
* <p>
* <code>TestSAXParsing</code> is a simple class that demonstrates
* how JAXP can be used to work with SAX (the Simple API for XML).
* </p>
public class TestSAXParsing {
* <p>Provide a static entry point.</p>
public static void main(String[] args) {
try {
if (args.length != 1) {
System.err.println ("Usage: java TestSAXParsing [filename]");
System.exit (1);
// Get SAX Parser Factory
SAXParserFactory factory = SAXParserFactory.newInstance();
// Turn on validation, and turn off namespaces
factory.setValidating(true);
factory.setNamespaceAware(false);
SAXParser parser = factory.newSAXParser();
parser.parse(new File(args[0]), new MyHandler());
} catch (ParserConfigurationException e) {
System.out.println("The underlying parser does not support the requested features.");
} catch (FactoryConfigurationError e) {
System.out.println("Error occurred obtaining SAX Parser Factory.");
} catch (Exception e) {
e.printStackTrace();
class MyHandler extends HandlerBase {
private Writer out;
public MyHandler() throws SAXException {
try {
out = new OutputStreamWriter(System.out, "UTF8");
} catch (IOException e) {
throw new SAXException("Error getting output handle.", e);
public void startDocument() throws SAXException {
print("<?xml version=\"1.0\"?>\n");
public void startElement(String elementName, AttributeList atts)
throws SAXException {
print("<" + elementName);
if (atts != null) {
for (int i=0, len = atts.getLength(); i<len; i++) {
print(" " + atts.getName(i) +
"=\"" + atts.getValue(i) + "\"");
print(">");
public void endElement(String elementName) throws SAXException {
print("</" + elementName + ">\n");
public void characters(char[] ch, int start, int len) throws SAXException {
print(new String(ch, start, len));
private void print(String s) throws SAXException {
try {
out.write(s);
out.flush();
} catch (IOException e) {
throw new SAXException("IO Error Occurred.", e);

Answer 1

I see that there are a number of code snippets on that page, for clarity I meant this one in particular. It checks for just about every parser known before calling default. Sorry for confusion. You wouldn't have to check for this many parsers, but I sometimes take Xerces if it is there over the default.
  XMLReader parser;
  try { // Xerces
    parser = XMLReaderFactory.createXMLReader(
     "org.apache.xerces.parsers.SAXParser"
  catch (SAXException e1) {
    try { // Crimson
      parser = XMLReaderFactory.createXMLReader(
       "org.apache.crimson.parser.XMLReaderImpl"
    catch (SAXException e2) {
      try { // ?lfred
        parser = XMLReaderFactory.createXMLReader(
         "gnu.xml.aelfred2.XmlReader"
      catch (SAXException e3) {
        try { // Piccolo
          parser = XMLReaderFactory.createXMLReader(
            "com.bluecast.xml.Piccolo"
        catch (SAXException e4) {
          try { // Oracle
            parser = XMLReaderFactory.createXMLReader(
              "oracle.xml.parser.v2.SAXParser"
          catch (SAXException e5) {
            try { // default
              parser = XMLReaderFactory.createXMLReader();
            catch (SAXException e6) {
              throw new NoClassDefFoundError(
                "No SAX parser is available");
                // or whatever exception your method is 
                // declared to throw
  }