While I am using a eclipse to run a file with "Run As" -> "Java
Application", it gives me the following error. Does anyone know what
the problem is?

<<The program>>:

/*
* Created on 2004-3-30
*/

import dori.jasper.engine.design.JasperDesign;
import dori.jasper.engine.JasperReport;
import dori.jasper.engine.JasperManager;
import dori.jasper.engine.JasperPrint;
import dori.jasper.engine.JRDataSource;
import dori.jasper.engine.data.JRBeanCollectionDataSource;
import dori.jasper.engine.JRException;
import dori.jasper.view.JasperViewer;
import dori.jasper.engine.JasperExportManager;

import java.util.Map;
import java.util.HashMap;

import java.util.Collection;
import java.util.Vector;

import java.util.StringTokenizer;

import java.io.IOException;
import java.io.BufferedReader;
import java.io.FileReader;

/**
* @author Tony
*
*/
public class Y3Report {
 private final static String PARAGRAPH =
   "Received in apparent good order and condition"
     + "except as otherwise noted the total number or"
     + "containers or other package or units enumerated"
     + "below for transportation from the place of receipt to"
     + "the place of delivery subject to the terms hereof. One"
     + "of the signed Bill of Lading must be surrendered duly"
     + "endorsed in exchange for the Goods or delivery"
     + "order. On presentation of this document (duly"
     + "endorsed) to the Carrier by or on behalf of the Holder,"
     + "the rights and liabilities arising in accordance with the"
     + "terms hereof shall (without prejudice to any rule of"
     + "common law or statute rendering them binding"
     + "on the Merchant) become binding in all respects"
     + "between the Carrier and the Holder as though the"
     + "contract evidenced hereby had been made between"
     + "them.";

 public static void main(String[] args) throws JRException {
   //    First, load JasperDesign from XML and compile it into
JasperReport
   JasperDesign jrDesign =
JasperManager.loadXmlDesign("y3report.xml");
   JasperReport jrReport = JasperManager.compileReport(jrDesign);

   //    Second, create a map of parameters to pass to the report.
   Map parameters = new HashMap();
   parameters.put("Paragraph", PARAGRAPH);

   //    Third, get a dataSource
   JRDataSource jrDataSource =
     new JRBeanCollectionDataSource(getBeanCollection());

   //    Fourth, create JasperPrint using fillReport() method
   JasperPrint jasperPrint =
     JasperManager.fillReport(jrReport, parameters, jrDataSource);

   //    You can use JasperPrint to create PDF
   //JasperManager.printReportToPdfFile(jasperPrint, "y3report.pdf");
   JasperExportManager.exportReportToHtmlFile(jasperPrint,
"y3report.pdf");
   JasperExportManager.exportReportToHtmlFile(jasperPrint,
"y3report.html");

   //    Or to view report in the JasperViewer
   JasperViewer.viewReport(jasperPrint);
 }

 private static Collection getBeanCollection() {
   Collection c = new Vector();

   try {
     BufferedReader br = new BufferedReader(new
FileReader("DB.txt"));
     String line;
     while ((line = br.readLine()) != null) {
       StringTokenizer st = new StringTokenizer(line, "|");
       DBBean dbBean = new DBBean();
       dbBean.setShipper(st.nextToken());
       dbBean.setConsignee(st.nextToken());
       dbBean.setNotifyParty(st.nextToken());
       dbBean.setOceanVNo(st.nextToken());
       dbBean.setPlaceOfReceipt(st.nextToken());
       dbBean.setPortOfLoading(st.nextToken());
       dbBean.setPortOfDischarge(st.nextToken());
       dbBean.setPortOfDelivery(st.nextToken());
       dbBean.setNumberOfOriginal(st.nextToken());
       dbBean.setMarksAndNumbers(st.nextToken());
       dbBean.setNumberAndType(st.nextToken());
       dbBean.setDescriptionOfGood(st.nextToken());
       dbBean.setGrossWeight(st.nextToken());
                dbBean.setMeasurementM3(st.nextToken());
       c.add(dbBean);
     }
   } catch (IOException e) {
     e.printStackTrace();
   }

   return c;
 }
}

<<The error>>:

java.lang.NoClassDefFoundError: Y3Report
Exception in thread "main"