Exception while excel processing after upload using commons file upload

Question

Hi all,
I am experiencing problem while creating a workbook after getting the input stream from the uploaded file. its not going catch block instead it is going to finally and giving null pointer exeption in finally as one variable in finally is not defined. the variable is defined in try as well as catch but during run time the variable is not getting assigned any value also. I'll put the code over here. please help me with a solution
import org.w3c.dom.* ;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import jxl.*;
import org.apache.commons.fileupload.*;
import org.apache.commons.fileupload.disk.*;
import org.apache.commons.fileupload.servlet.*;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFRow;
public class CescoreUploadServlet extends baseHttpServlet
     private DataSource cesDS = null;
     public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
          doPost(req, res);
     public void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
          String targetPage = null;
          File f = null;
          System.out.println("Upload Controller");
          HttpSession session = req.getSession(true);
          try
               if(cesDS == null){
                    cesDS = new JNDIDataSource(getServletContext().getInitParameter(Constants.DATA_SOURCE_NAME));
               CesRepository cRep = new CesRepository(cesDS);
               if (session.getAttribute("DataContainerInfo") == null) {
                    System.out.println("Initializing DataContainerInfo");
                    DataContainer DataContainer = new DataContainer();
                    cRep.setInitialParameters(DataContainer);
                    session.setAttribute("DataContainerInfo",DataContainer);
               else System.out.println("DataContainerInfo is available");
               UserInfo userInfo = null;               
               String login_id = req.getRemoteUser();
               if(session.getAttribute("UserID") != null) login_id = (String)session.getAttribute("UserID");
               if(session.getAttribute("userProfile") == null ) session.setAttribute("userProfile", cRep.getUserInfo(login_id));
               userInfo = (UserInfo)session.getAttribute("userProfile");
               System.out.println("<<<<<< userInfo contains : "+userInfo.getHrID()+" >>>>>>");
               String projIdValue = null;
               String msg = null;
               boolean isMultipart = FileUpload.isMultipartContent(req);
               if(isMultipart){
                    System.out.println("is MultiPart");
                    DiskFileUpload upload = new DiskFileUpload();
                    List fileList = upload.parseRequest(req);
                    InputStream uploadedFileStream = null;
                    String uploadedFileName = null;
                    ArrayList impArray = new ArrayList();
                    Iterator iter = fileList.iterator();
                    while (iter.hasNext()) {
                         System.out.println("inside while");
                         FileItem item = (FileItem) iter.next();
                         if (!item.isFormField()) {
                              System.out.println("item is not form field");
                              if (item.getSize() < 1)
                                   throw new Exception("No file was uploaded");
                              else
                                   uploadedFileName = item.getName();
                                   System.out.println("uploaded file name "+uploadedFileName);
                                   System.out.println("uploaded file size is "+item.getSize());
                                   uploadedFileStream = item.getInputStream();
                                   System.out.println("uploaded input stream available size is "+uploadedFileStream.available());
                         else
                              System.out.println("item is form field");
                              String key     = item.getFieldName();
                              String value = item.getString();
                              System.out.println("key is"+key);
                              System.out.println("value is"+value);
                              if(key.equals("projectId2")){
                                   projIdValue = value;
                    System.out.println("outside while");
                    POIFSFileSystem fs = new POIFSFileSystem(uploadedFileStream);
                    System.out.println("got POIFSFileSystem");//this is been printed in logs
                    HSSFWorkbook wb = new HSSFWorkbook(fs);//it is breaking over here
                    System.out.println("got HSSFWorkbook");//this is not been printed in logs
                    HSSFSheet sheet = wb.getSheetAt(0);
                    System.out.println("got HSSFSheet");
                    Iterator rows = sheet.rowIterator();
                    if(rows.hasNext()){
                    while( rows.hasNext() ) {
                         System.out.println("rows iteration");
                         HSSFRow row = (HSSFRow) rows.next();
                         Iterator cells = row.cellIterator();
                         while( cells.hasNext() ) {
                              System.out.println("cell iteration");
                              HSSFCell cell = (HSSFCell) cells.next();
                              HashMap hm = new HashMap();//if everything is fine i'll use this hashmap to store values
                         System.out.println("CES UPLOAD.SERVLET. After adding");
                         msg = "Attendees have been added successfully";
                         req.setAttribute("msgText", msg);
                         targetPage = "/ces_disp.jsp";
                    else
                         throw new Exception("The Excel Sheet Uploaded has no entries. Please check and try again");
               else{
                    throw new Exception("The Form is not Multipart");
          catch (Exception e)
               System.out.println("CES UPLOAD.SERVLET.EXCEPTION ::: Exception");
               targetPage = "/ces_disp.jsp";
               if(e != null) req.setAttribute("msgText", e.getMessage());
               else req.setAttribute(Constants.EXCEPTION_ATTR_NAME, new Exception("Unknown Exception"));
               e.printStackTrace();
          finally{
               System.out.println("CES UPLOAD.SERVLET. ::: Finally");
               ServletContext stx = getServletConfig().getServletContext();
               RequestDispatcher dispatcher = sCx.getRequestDispatcher(targetPage);
               dispatcher.forward(req, res);
Message was edited by: Noufal
Noufal_k
Message was edited by:
Noufal_k

Answer 1

import org.w3c.dom.* ;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import jxl.*;
import org.apache.commons.fileupload.*;
import org.apache.commons.fileupload.disk.*;
import org.apache.commons.fileupload.servlet.*;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFRow;
public class CescoreUploadServlet extends baseHttpServlet
private DataSource cesDS = null;
public void doGet(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
doPost(req, res);
public void doPost(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
//including only relevant code
String targetPage = null;
System.out.println("Upload Controller");
HttpSession session = req.getSession(true);
try
String projIdValue = null;
String msg = null;
boolean isMultipart = FileUpload.isMultipartContent(req);
if(isMultipart){
System.out.println("is MultiPart");
DiskFileUpload upload = new DiskFileUpload();
List fileList = upload.parseRequest(req);
InputStream uploadedFileStream = null;
String uploadedFileName = null;
Iterator iter = fileList.iterator();
while (iter.hasNext()) {
System.out.println("inside while");
FileItem item = (FileItem) iter.next();
if (!item.isFormField()) {
System.out.println("item is not form field");
if (item.getSize() < 1)
throw new Exception("No file was uploaded");
else
uploadedFileName = item.getName();
System.out.println("uploaded file name "+uploadedFileName);//printing  c:/excelsheets/fileToUpload.xls
System.out.println("uploaded file size is "+item.getSize());//printing size is 15872
uploadedFileStream = item.getInputStream();
System.out.println("uploaded input stream available size is "+uploadedFileStream.available());//printing available input stream size is 15872
else
System.out.println("item is form field");
String key = item.getFieldName();
String value = item.getString();
System.out.println("key is"+key);
System.out.println("value is"+value);
if(key.equals("projectId2")){
projIdValue = value;
System.out.println("outside while");
POIFSFileSystem fs = new POIFSFileSystem(uploadedFileStream);
System.out.println("got POIFSFileSystem");//this is been printed in logs
HSSFWorkbook wb = new HSSFWorkbook(fs);//it is breaking over here
System.out.println("got HSSFWorkbook");//this is not been printed in logs
HSSFSheet sheet = wb.getSheetAt(0);
System.out.println("got HSSFSheet");
Iterator rows = sheet.rowIterator();
if(rows.hasNext()){
while( rows.hasNext() ) {
System.out.println("rows iteration");
HSSFRow row = (HSSFRow) rows.next();
Iterator cells = row.cellIterator();
while( cells.hasNext() ) {
System.out.println("cell iteration");
HSSFCell cell = (HSSFCell) cells.next();
HashMap hm = new HashMap();//if everything is fine i'll use this hashmap to store values
System.out.println("CES UPLOAD.SERVLET. After adding");
msg = "Attendees have been added successfully";
req.setAttribute("msgText", msg);
targetPage = "/ces_disp.jsp";
else
throw new Exception("The Excel Sheet Uploaded has no entries. Please check and try again");
else{
throw new Exception("The Form is not Multipart");
catch (Exception e)
System.out.println("CES UPLOAD.SERVLET.EXCEPTION ::: Exception");
targetPage = "/ces_disp.jsp";
if(e != null) req.setAttribute("msgText", e.getMessage());
else req.setAttribute(Constants.EXCEPTION_ATTR_NAME, new Exception("Unknown Exception"));
e.printStackTrace();
finally{
System.out.println("CES UPLOAD.SERVLET. ::: Finally");
ServletContext stx = getServletConfig().getServletContext();
RequestDispatcher dispatcher = stx.getRequestDispatcher(targetPage);//throwing null pointer exception for this line
dispatcher.forward(req, res);
}