Unable to create a spredsheet using XSSFWorkbook

Question

Hi here's my code for creating a spreadsheet using XSSFWorkbook:

import java.io.File;
import java.io.FileOutputStream;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class Writesheet 
{
   public static void main(String[] args) throws Exception 
   {
      //Create blank workbook
      XSSFWorkbook workbook = new XSSFWorkbook(); 
      //Create a blank sheet
      XSSFSheet spreadsheet = workbook.createSheet( 
      " Employee Info ");
      //Create row object
      XSSFRow row;
      //This data needs to be written (Object[])
      Map < String, Object[] > empinfo = 
      new TreeMap < String, Object[] >();
      empinfo.put( "1", new Object[] { 
      "EMP ID", "EMP NAME", "DESIGNATION" });
      empinfo.put( "2", new Object[] { 
      "tp01", "Gopal", "Technical Manager" });
      empinfo.put( "3", new Object[] { 
      "tp02", "Manisha", "Proof Reader" });
      empinfo.put( "4", new Object[] { 
      "tp03", "Masthan", "Technical Writer" });
      empinfo.put( "5", new Object[] { 
      "tp04", "Satish", "Technical Writer" });
      empinfo.put( "6", new Object[] { 
      "tp05", "Krishna", "Technical Writer" });
      //Iterate over data and write to sheet
      Set < String > keyid = empinfo.keySet();
      int rowid = 0;
      for (String key : keyid)
      {
         row = spreadsheet.createRow(rowid++);
         Object [] objectArr = empinfo.get(key);
         int cellid = 0;
         for (Object obj : objectArr)
         {
            Cell cell = row.createCell(cellid++);
            cell.setCellValue((String)obj);
         }
      }
      //Write the workbook in file system
      FileOutputStream out = new FileOutputStream( 
      new File("Writesheet.xlsx"));
      workbook.write(out);
      out.close();
      System.out.println( 
      "Writesheet.xlsx written successfully" );
   }
}

But when I try to run it, I get the following ClassNotFound Exception:

Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/xmlbeans/XmlException at plotgz.XSSFParser.main(XSSFParser.java:17) Caused by: java.lang.ClassNotFoundException: org.apache.xmlbeans.XmlException at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:425) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ... 1 more

I've added the following jar in the classpath:

poi-ooxml-3.5-beta5.jar

I'm unable to figure out what is causing this exception. Any help would be appreciated. Thanks.