Error reading zip file containing an excel file

Question

Hi all,
Using servlets I am able to zip an excel file using java.util.zip package. The excel file is created using POI API.
While I save and extract the zip file on my machine and then open the file in MS Excel. Excel pops a message saying "MS Office Excel has encountered a problem and need to close" and it gives me an option to "Recover my work and restart MS Office Excel". I select the option and then MS Excel does a document recovery and I am able to view my data. I get an excel repair log file saying as follows
"Microsoft Office Excel File Repair Log
Errors were detected in file 'C:\Documents and Settings\JohnDoe\Desktop\excel\test.xls'
The following is a list of repairs:
Damage to the file was so extensive that repairs were not possible. Excel attempted to recover your formulas and values, but some data may have been lost or corrupted.
I have attached my servlet code down below I suspect there is a problem with PrintWriter to output or do I need to use OutputStream to write excel data.
Below is my servlet code:
import java.io.*;
import javax.servlet.*;
import org.apache.log4j.Logger;
import java.util.*;
import java.util.zip.*;
import java.net.*;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.hssf.record.*;
import org.apache.poi.hssf.util.*;
public class ZipServlet extends HttpServlet {
     * @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest,
     * javax.servlet.http.HttpServletResponse)
     public void doGet(HttpServletRequest request, HttpServletResponse response)
          throws ServletException, IOException {
          makeZip(request, response, "GET");
     * @see javax.servlet.http.HttpServlet#doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
     protected void doPost(HttpServletRequest request, HttpServletResponse response)
               throws ServletException, IOException {
               makeZip(request, response, "POST");
     public void makeZip(HttpServletRequest request, HttpServletResponse response, String methodGetPost) {
          Logger logger = Logger.getLogger(ZipServlet.class);
          try
               int id=1;
               ServletContext sc = getServletContext();
     HttpSession session = request.getSession();          
               ConnectionPoolManager cpm = (ConnectionPoolManager)sc.getAttribute("CONNECTION_POOL_MANAGER");
               ConnectionPool cp = cpm.getConnectionPool(id);
          createTestExcelZip(request,response,methodGetPost,session);
          } catch (Exception e2) {
     public void createTestExcelZip(HttpServletRequest request, HttpServletResponse response,
               String methodGetPost,HttpSession session
               )throws ServletException, IOException
          Logger logger = Logger.getLogger(ZipServlet.class);
          try
          {      //Create an Excel Workbook and placing value "Test" in the first cell
               HSSFWorkbook wb = new HSSFWorkbook();
               HSSFSheet sheet = wb.createSheet("new sheet");
               HSSFCell cell=null;
               HSSFRow row = sheet.createRow((short) 0);
               short column = 0;
               cell = row.createCell(column);
               cell.setCellValue(new HSSFRichTextString("Test"));
               HSSFCellStyle fontStyle = wb.createCellStyle();
          HSSFFont f = wb.createFont();
          f.setFontHeight((short) 200);
          f.setBoldweight(HSSFFont.BOLDWEIGHT_BOLD);
          fontStyle.setFont(f);
          cell.setCellStyle(fontStyle);
          response.setContentType("application/zip");
               response.setHeader("Content-Disposition","attachment; filename=zipExcelRecordFiles.zip;");
               int BUFFER = 2048;
               byte buf[]=new byte[300000];
               ByteArrayOutputStream baos = new ByteArrayOutputStream();
               ZipOutputStream zos = new ZipOutputStream( baos );
               ByteArrayInputStream is = null;
               BufferedInputStream origin = null;
               byte[] b = null;
               String fileName = null;
               b = wb.getBytes();
               fileName = "testExcelRecords.xls";
               try
               is = new ByteArrayInputStream(b);
               origin = new BufferedInputStream(is, BUFFER);
               zos.putNextEntry(new ZipEntry(fileName)); // Add ZIP entry to output stream.
          int count;
          while((count = origin.read(buf, 0, BUFFER)) != -1)
          zos.write(buf, 0, count);
          zos.closeEntry(); // Complete the entry
               is.close();
               }catch(Exception e)
                    logger.error(e);
               zos.close();
          PrintWriter pr = response.getWriter();
               pr.write(baos.toString("ISO-8859-1"));
               pr.close();
          catch(Exception e)
          logger.error(e);     
     * @see javax.servlet.GenericServlet#destroy()
     public void destroy() {
Any help would be appreciated.
Regards
jdcunha

Answer 1

Jdcunha,
I am new to the field but encountered the same problem and recently found a solution. Hope this helps.
For my project I wanted to create individual Excel 2003 workbooks for each file I created. Excel would give me the same error it gave you when I used the same HSSFWorkbook object. I tried creating a new Workbook object each time, but ran into the same issue.
I ended up fixing the error by creating a new instance of my write-to-excel class each time I wanted to create a new workbook, instead of just recreating a new HSSFWorkbook object. It works perfectly and the Excel errors don't show. It may also be important to note I used OutputStream, I did not try it with printwriter.