Include Schema Name When Creating XML

I have a Java program that creates an XML string and I wanted to pass
in a schema name to include when the DOM object is created. Here is my
Java code. The startDocument method automatically adds "<?xml
version="1.0" encoding="UTF-8"?>". Is there something I can add to
this method to write out the schema location?

package igxml;

import java.io.*;
import java.util.Vector;

import org.w3c.dom.*;
import org.xml.sax.helpers.DefaultHandler;
import javax.xml.parsers.*;
import org.apache.xml.serialize.*;

public class IgXMLBuild extends DefaultHandler {

    Document doc;
    Element root;
    Element currentElement;
    Element previousElement;
    Element childElement;
    int elementIndex;
    Text textData;
    private Vector elementList = new Vector();

    /**
     * This method is used to create a new XML document (DOM object)
     * @param rootName This is the name of the Root element.
     */
    public void startDocument(String rootName)
    {

        // Create the DOM object
        DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
     factory.setNamespaceAware(true);
        DocumentBuilder builder = null;
        try {
            builder = factory.newDocumentBuilder();
        } catch (ParserConfigurationException e) {
         System.out.println("Could not locate a JAXP DocumentBuilder
class");
        }
        doc = builder.newDocument();

        /* create the root node */
        root = doc.createElement(rootName);

        /* Initialiaze the vector that will hold the element pointers. */
        elementList.clear();
        elementList.addElement(root);
        currentElement = root;
        return;
    }

    /**
     * This method will create the open tag for a new element.
     * @param elementName The name of the new element.
     */
    public void startTag (String elementName)
    {
        /* create a row node */
        currentElement = doc.createElement(elementName);

        /* add Element ID to Vector */
        elementList.addElement(currentElement);
        return;
    }

    /**
     * This method will create the end tag for the last open tag
(startTag) that was created.
     * @param elementName This parameter is not used in the function. It
is for documentation purposes only.
     */
    public void endTag(String elementName)
    {
        /* append the row node to the parent node */
        elementIndex = elementList.indexOf(currentElement);
        elementIndex += -1;
        previousElement = (Element)elementList.get(elementIndex);
        previousElement.appendChild(currentElement);
        elementIndex += 1;
        elementList.remove(elementIndex);
        currentElement = previousElement;
    }

    /**
     * This method is used to create an XML Open/Close tag with data
     * @param elementName XML Tag Name for open/close tag
     * @param elementValue Data between open/close tag
     */
    public void addTag(String elementName, String elementValue)
    {
        childElement = doc.createElement(elementName);
        textData = doc.createTextNode(elementValue);
        childElement.appendChild(textData);
        currentElement.appendChild(childElement);
    }

    /**
     * This method is used to create all of the close tags for
     * any tags that were opened (startTag) and not yet closed.
     */
    public void closeTags(){
     while (root != currentElement) {
     endTag("");
     currentElement = (Element)elementList.lastElement();
     }
    }

    /**
     * This method is called when you are done building the XML document.
     * It will close any tags that were not yet closed.
     * @return The XML document will be returned as a String.
     */
    public String finishDocument()
    {
     closeTags();

        /* append the root node to the document */
        doc.appendChild(root);

     try {
     // Serialize the document
     StringWriter out;
     out = new StringWriter();
     XMLSerializer serializer = new XMLSerializer(out, new
OutputFormat(doc));
     serializer.serialize(doc);
     String xmlString = out.toString();
     return xmlString;
     } catch (IOException e) {
     System.err.println(e);
     return e.toString();
     }
    }
}