Servlet

[palmach]

Hola, como puedo guardar lo que me muestara el servlet a un arvhico .xml?

Código:

package com.facturas.servlets;

import java.io.ByteArrayOutputStream;
import java.io.IOException;

import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


import org.apache.xml.serialize.OutputFormat;
import org.apache.xml.serialize.XMLSerializer;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.w3c.dom.Element;

import com.facturas.converters.ConverterEFACE;

/**
 * Servlet implementation class FacturasG4S
 */
public class FacturasG4S extends HttpServlet {
	private static final long serialVersionUID = 1L;

    /**
     * Default constructor. 
     */
    public FacturasG4S() {
        // TODO Auto-generated constructor stub

    }

    private WebApplicationContext getContext()
    {
		ServletContext servletContext = this.getServletContext();
		WebApplicationContext wac = WebApplicationContextUtils.
				getRequiredWebApplicationContext(servletContext);
		
		return wac;
    }

	  private String printDOM(Element xmlDoc) throws Exception
	  {
		  String retorno = "";

	    OutputFormat outputFormat = new OutputFormat("XML","UTF-8",true);
	    ByteArrayOutputStream baos = new ByteArrayOutputStream();

	    XMLSerializer xmlSerializer = new XMLSerializer(baos, outputFormat);

	    xmlSerializer.asDOMSerializer();

	    xmlSerializer.serialize(xmlDoc);

	    if(baos != null)
	    {
	    	retorno = baos.toString();
	    }
	    
	    return retorno;
	    
	  }
    
    
	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		try
		{
			
			ConverterEFACE converter = (ConverterEFACE)getContext().getBean("converterEFACE");
			
			String facturaId = request.getParameter("id");
		
			if((facturaId != null) && (!facturaId.equals("")))
			{
				Element elemento = converter.generateElement(Long.parseLong(facturaId));
				response.getOutputStream().println(printDOM(elemento));
				response.getOutputStream().close();
			   
			}
			
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		
		
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
	}

}