New to Java

I have a problem when loading the servlet that would compile the jrxml and export it in a PDF format. I tested a sample jrxml that I found in a tutorial and put it in my CLASSES folder in WEB-INF togther with the servlet. The error occured when calling the servlet.
error

net.sf.jasperreports.engine.JRException: Error loading object from InputStream
	at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:196)
	at net.sf.jasperreports.engine.JasperFillManager.fillReport(JasperFillManager.java:580)
	at net.sf.jasperreports.engine.JasperRunManager.runReportToPdfStream(JasperRunManager.java:368)
	at EmptyDSReportServlet.doGet(EmptyDSReportServlet.java:26)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:126)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:103)
	at com.caucho.server.http.FilterChainServlet.doFilter(FilterChainServlet.java:96)
	at com.caucho.server.http.Invocation.service(Invocation.java:315)
	at com.caucho.server.http.CacheInvocation.service(CacheInvocation.java:135)
	at com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:253)
	at com.caucho.server.http.HttpRequest.handleConnection(HttpRequest.java:171)
	at com.caucho.server.TcpConnection.run(TcpConnection.java:139)
	at java.lang.Thread.run(Thread.java:619)
Caused by: java.io.StreamCorruptedException: invalid stream header: 3C3F786D
	at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:783)
	at java.io.ObjectInputStream.<init>(ObjectInputStream.java:280)
	at net.sf.jasperreports.engine.util.JRLoader.loadObject(JRLoader.java:191)
	... 12 more

Here is the jrxml that I put inside the classes folder together with the servlet:

<?xml version="1.0"?>
<!DOCTYPE jasperReport
PUBLIC "-//JasperReports//DTD Report Design//EN"
"http://jasperreports.sourceforge.net/dtds/jasperreport.dtd">
<jasperReport name="EmptyDataSourceReport">
<detail>
<band height="20">
<staticText>
<reportElement x="20" y="0" width="200" height="20"/>
<text><![CDATA[This simple report contains only static
data.]]></text>
</staticText>
</band>
</detail>
</jasperReport>

finally, the servlet:

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.io.StringWriter;
import java.util.HashMap;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.jasperreports.engine.JREmptyDataSource;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.JasperRunManager;
public class EmptyDSReportServlet extends HttpServlet
{
protected void doGet(HttpServletRequest request,HttpServletResponse
response) throws ServletException, IOException
{
ServletOutputStream servletOutputStream =
response.getOutputStream();
InputStream reportStream = getServletConfig().getServletContext()
.getResourceAsStream("EmptyDataSourceReport.jrxml");
try
{
JasperRunManager.runReportToPdfStream(reportStream,
servletOutputStream, new HashMap(), new JREmptyDataSource());
response.setContentType("application/pdf");
servletOutputStream.flush();
servletOutputStream.close();
}
catch (JRException e)
{
// display stack trace in the browser
StringWriter stringWriter = new StringWriter();
PrintWriter printWriter = new PrintWriter(stringWriter);
e.printStackTrace(printWriter);
response.setContentType("text/plain");
response.getOutputStream().print(stringWriter.toString());
}
}
}