Hello.
I have this error:

javax.servlet.ServletException: java.lang.NoSuchMethodError: org.apache.poi.hssf.usermodel.HSSFSheet.setRightTo Left(Z)V

Help mee...My files :

class :

package newpackage;

import java.io.OutputStream;
import java.io.PrintWriter;
import java.sql.Connection;
import java.util.HashMap;
import java.util.Map;
import java.util.ResourceBundle;
import javax.faces.context.FacesContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.jasperreports.engine.JRExporterParameter;
import net.sf.jasperreports.engine.JasperCompileManager;
import net.sf.jasperreports.engine.JasperFillManager;
import net.sf.jasperreports.engine.JasperPrint;
import net.sf.jasperreports.engine.JasperReport;
import net.sf.jasperreports.engine.export.JRHtmlExporter;
import net.sf.jasperreports.engine.export.JRHtmlExporterP arameter;
import net.sf.jasperreports.engine.export.JRPdfExporter;
import net.sf.jasperreports.engine.export.JRRtfExporter;
import net.sf.jasperreports.engine.export.JRXlsExporter;
import java.awt.event.*;
import java.io.IOException;
import java.sql.SQLException;
import net.sf.jasperreports.engine.JRException;
import net.sf.jasperreports.engine.design.JasperDesign;
import net.sf.jasperreports.engine.xml.JRXmlLoader;
import java.lang.Exception.*;
import java.lang.Class.*;
import javax.servlet.*;
import java.io.File;
import java.io.*;
import java.sql.DriverManager;


public class NewClass {

public NewClass() {
}

public String excelRapor() throws IOException, ClassNotFoundException, SQLException, JRException {
{

//
Connection connection;

Class.forName("org.apache.derby.jdbc.ClientDriver" );

connection = DriverManager.getConnection("jdbc:derby://localhost:1527/denemeRapor","admin","123");

HashMap jasperParameter = new HashMap();

ServletContext servletContext = (ServletContext) FacesContext.getCurrentInstance().getExternalConte xt().getContext();

// String jrxmlFile = servletContext.getRealPath("") + File.separator + "report2.jrxml";
String jrxmlFile="C:\\Users\\admin\\Documents\\NetBeansPr ojects\\WebApplication6\\src\\java\\newpackage\\re port4.jrxml";

JasperDesign jasperDesign = JRXmlLoader.load(jrxmlFile);

JasperReport jasperReport;

jasperReport = JasperCompileManager.compileReport(jasperDesign);

JasperPrint jasperPrint = JasperFillManager.fillReport(jasperReport, jasperParameter, connection);

byte bytes[] = new byte[10];
JRXlsExporter exporter = new JRXlsExporter();

ByteArrayOutputStream xlsReport = new ByteArrayOutputStream();

exporter.setParameter(JRExporterParameter.JASPER_P RINT, jasperPrint);

exporter.setParameter(JRExporterParameter.OUTPUT_S TREAM, xlsReport);

exporter.setParameter(JRExporterParameter.OUTPUT_F ILE, "C:\\JSP\\");

exporter.setParameter(JRExporterParameter.OUTPUT_F ILE_NAME, "sample.xls");

exporter.exportReport();

bytes = xlsReport.toByteArray();

xlsReport.close();


connection.close();

return "ok";

}
}
}

welcomeJSF.jsp :

<%@page contentType="text/html" pageEncoding="UTF-8"%>

<%@taglib prefix="f" uri="http://java.sun.com/jsf/core"%>
<%@taglib prefix="h" uri="http://java.sun.com/jsf/html"%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">

<%--
This file is an entry point for JavaServer Faces application.
--%>
<f:view>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
<title>JSP Page</title>
</head>
<body>
<h1><h:outputText value="JavaServer Faces"/></h1>

<% newpackage.NewClass obj=new newpackage.NewClass();%>
<%= obj.excelRapor()%>




</body>
</html>
</f:view>