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getCellType() always returns 0 (Numeric)

When I read an xls file with Apache POI, I always receive the value 0 from getCellType(). That is incorrect. I have other types of data inserted in the sheet. And I don't really understand why this is happening.
This is what my logger says every time it parses a cell:
Type = 0
Does anyone know or have a clue why is this happening?
HSSFWorkbook wb = new HSSFWorkbook(inputStream);
HSSFSheet sheet=wb.getSheetAt(0);
HSSFRow row;
HSSFCell cell;
Iterator rows = sheet.rowIterator();
while (rows.hasNext())
{
row=(HSSFRow) rows.next();
Iterator cells = row.cellIterator();
while (cells.hasNext())
{
cell=(HSSFCell) cells.next();
log4Debug.debug(" cellCollumnr = "+cell.getCellNum());
log4Debug.debug(" cellRow = "+row.getRowNum());
log4Debug.debug(" Type = "+cell.getCellType());
}
}

Workbook takes long time to generate excel file

I'm trying to generate excel file with 200k records. But it is taking almost 2 hours to generate the file.
Here is my code of generating excel file.
Workbook workbook=null;
csvFileName = userId+"_Records_"+new SimpleDateFormat("yyyyMMddHHmmss")
.format(new Date())+".xls";
path = ReadPropertyFile.getProperties("download.reports.path");
misService.insertXLSRecord(ackNo,"-",null, VspCommonConstants.getIpFromRequest(request),
new Date(), userId,"N",userReportRoleId);
workbook = getWorkbook(path+csvFileName);
Sheet sheet = workbook.createSheet(WorkbookUtil.createSafeSheetName(studAppForm.get(0)
.getScheme_Id()+"_"+studAppForm.get(0).getEFP_Scholarship_Name(),'_'));
if(schemeQuestionData.containsKey(currSheetSchemeId))
createXLSHeaders(sheet,schemeQuestionData.get(currSheetSchemeId));
Row row = sheet.createRow(++rowCount);
currAppId=studAppForm.get(j).getApp_Id().toString();
jspTableAppIds.remove(jspTableAppIds.indexOf(new BigInteger(currAppId)));
writeBook(studAppForm.get(j), row);
Here is my createXLSHeaders method to create header
void createXLSHeaders( Sheet sheet, List<SchemeMasterBean> schemeMasterBeanList){
LOGGER.info("Creating XLS SheetHeaders for sheet "+sheet.getSheetName());
// Sheet sheet = workbook.createSheet();
Row header = sheet.createRow(0);
header.createCell(0).setCellValue("APPLICATION ID");
header.createCell(1).setCellValue("APPLICATION STATUS");
header.createCell(2).setCellValue("APPLICATION DATE");
header.createCell(3).setCellValue("SCHEME/SCHOLARSHIP APPLIED");
header.createCell(4).setCellValue("SCHEME ID");
header.createCell(5).setCellValue("STUDENT ID");
header.createCell(6).setCellValue("STUDENT FULL NAME");
.
.
.
62 heading...
int i=73;
if(schemeMasterBeanList!=null)
for(SchemeMasterBean schemeMasterBean :schemeMasterBeanList){
if(!schemeMasterBean.getSmSchemeType().equals("5") &&
!schemeMasterBean.getSmSchemeType().equals("6")){
header.createCell(i).setCellValue(schemeMasterBean.getSmScholarshipName());
i++;
}
}
}
and finally writebook method
private void writeBook(StudentAppFormVsp saf, Row row) throws JSONException {
Cell cell = row.createCell(0);
cell.setCellValue(saf.getApp_Id()!=null?saf.getApp_Id().toString():"");
cell = row.createCell(1);
cell.setCellValue(saf.getApp_Status()!=null?getApplicationStatusMap().get(saf.getApp_Status()):"");
cell = row.createCell(2);
cell.setCellValue(saf.getCrtn_time()!=null?saf.getCrtn_time().toString():"");
cell = row.createCell(3);
cell.setCellValue(saf.getEFP_Scholarship_Name()!=null?saf.getEFP_Scholarship_Name().toString():"");
cell = row.createCell(4);
cell.setCellValue(saf.getScheme_Id()!=null?saf.getScheme_Id().toString():"");
cell = row.createCell(5);
cell.setCellValue(saf.getStud_Id()!=null?saf.getStud_Id().toString():"");
.
.
62 rows
}
How to reduce the excel sheet generation time?

First: play around with memory for the application if possible.
Then: the tip on using a profiler is really worth the effort.
Any DOM, XML, Excel or otherwise often suffer from location references searching from top to the actual position.
Creating a DOM instead of writing sequentially is costly with respect to memory, and can slow things down. Maybe consider this.
You could make two loop: writing to a CSV file, and then creating an XLS(X).
Then you know where the complexity resides.
The following (I rewrote a bit) is slightly suspect: toString + new BigInteger points to a conversion; I hope not from BigInteger to String to BigInteger.
StudentAppFormVsp saf = studAppForm.get(j);
currAppId = saf.getApp_Id().toString();
jspTableAppIds.remove(jspTableAppIds.indexOf(BigInteger.valueOf(currAppId)));
writeBook(saf, row);

Java code not printing all rows from excel file

I have an excel file with 6663 rows. I want to read all the rows and columns in the excel file and print them out on my console in eclipse. Here is what I have tried to achieve this:
public class ExcelReader {
public static final String SAMPLE_XLSX_FILE_PATH = "K:\\Documents\\Project\\Netword_GUI\\Netword_GUI\\src\\libs\\cc2017.xlsx";
public static void main(String[] args) throws IOException, InvalidFormatException {
// Creating a Workbook from an Excel file (.xls or .xlsx)
Workbook workbook = WorkbookFactory.create(new File(SAMPLE_XLSX_FILE_PATH));
// Retrieving the number of sheets in the Workbook
System.out.println("Workbook has " + workbook.getNumberOfSheets() + " Sheets : ");
/*
=============================================================
Iterating over all the sheets in the workbook (Multiple ways)
=============================================================
*/
// You can obtain a sheetIterator and iterate over it
Iterator<Sheet> sheetIterator = workbook.sheetIterator();
System.out.println("Retrieving Sheets using Iterator");
while (sheetIterator.hasNext()) {
Sheet sheet = sheetIterator.next();
//System.out.println(sheet.getRow(0));
System.out.println("=> " + sheet.getSheetName());
}
// Getting the Sheet at index zero
Sheet sheet = workbook.getSheetAt(0);
// Create a DataFormatter to format and get each cell's value as String
DataFormatter dataFormatter = new DataFormatter();
// You can obtain a rowIterator and columnIterator and iterate over them
System.out.println("\n\nIterating over Rows and Columns using Iterator\n");
Iterator<Row> rowIterator = sheet.rowIterator();
while (rowIterator.hasNext()) {
Row row = rowIterator.next();
// Now let's iterate over the columns of the current row
Iterator<Cell> cellIterator = row.cellIterator();
while (cellIterator.hasNext()) {
Cell cell = cellIterator.next();
String cellValue = dataFormatter.formatCellValue(cell);
System.out.print(cellValue + "\t");
}
System.out.println();
}
if (sheet.getActiveCell() == null) {
// Closing the workbook
workbook.close();
}
}
}
The intention of this code is to display all the rows and columns. At the moment this code just shows roughly about 200 rows but all the columns for these rows are showing as intended. It also seems to be displaying the rows in a random order although, every time I run it the same rows show in the same random order. I would appreciate any solution in order to display all of the 6663 rows in the correct order including the headers (first row). Thank you in advance.

If you are running this inside Eclipse you are probably hitting the limit on the size of the Console output.
You can change the limit in the Preferences in the 'Run/Debug > Console' page. You can change the maximum number of characters or turn off the limiting altogether (but this can lead to out of memory errors).

Java Apache POI Unable to Get Code Working Correctly

Edit - thanks for responses. Have made changes and as suggested found the problem was a NOW on empty rows.
I am writing a program that loads various excel sheets and provides an output based on certain criteria. See code below. My problem is that the code does not write or save to the DISPLAY sheet. I realise the code below is not particularly neat but have copy pasted to check if I can get anything to save. If I comment out everything within the loop and try to write to the cell at the end before I save, it works and shows in the sheet. If I don't comment out the data formatter part it doesn't work even when trying to write to cell just before the part where I am saving output file. I am guessing the problem is caused by the data formatter, but I can't work out why.
public void checkForChanges() {
try {
FileInputStream fsIP = new FileInputStream("Change.xls");
HSSFWorkbook fWorkbook = new HSSFWorkbook(fsIP);
HSSFSheet recipeSheet = fWorkbook.getSheet("RECIPE STEPS");
HSSFSheet fromSheet = fWorkbook.getSheet("FROM FORMAT");
HSSFSheet toSheet = fWorkbook.getSheet("TO FORMAT");
HSSFSheet displaySheet = fWorkbook.getSheet("DISPLAY");
for (int i = 0; i < 30; i++) {
DataFormatter recipeFormatter = new DataFormatter();
HSSFRow recipeRow = recipeSheet.getRow(i);
HSSFCell recipeCellsColumnA = recipeRow.getCell(0);
String recipeCellValueColumnA = recipeFormatter.formatCellValue(recipeCellsColumnA);
System.out.println(recipeCellValueColumnA);
HSSFCell recipeCellsColumnB = recipeRow.getCell(1);
String recipeCellValueColumnB = recipeFormatter.formatCellValue(recipeCellsColumnB);
System.out.println(recipeCellValueColumnB);
DataFormatter fromFormatter = new DataFormatter();
HSSFRow fromRow = fromSheet.getRow(i);
HSSFCell fromCells = fromRow.getCell(0);
String fromCellValue = fromFormatter.formatCellValue(fromCells);
System.out.println(fromCellValue);
DataFormatter toFormatter = new DataFormatter();
HSSFRow toRow = toSheet.getRow(i);
HSSFCell toCells = toRow.getCell(0);
String toCellValue = toFormatter.formatCellValue(toCells);
System.out.println(toCellValue);
if (recipeCellValueColumnB.equals("YES") && !fromCellValue.equals(toCellValue)) {
System.out.println("PUT VALUE FROM 'TO FORMAT' COLUMN A ROW I INTO 'DISPLAY' SHEET CELL COLUMN B ROW I");
System.out.println("PUT VALUE FROM 'RECIPE STEPS' COLUMN A ROW I INTO 'DISPLAY' SHEET CELL COLUMN A ROW I");
Row row = displaySheet.createRow(0);
Cell cell = row.createCell(0);
cell.setCellValue("TEST");
} else if (recipeCellValueColumnB.equals("YES") && fromCellValue.equals(toCellValue)) {
System.out.println("SET CELL IN 'DISPLAY' SHEET COLUMN A ROW I TO '' ");
System.out.println("SET CELL IN 'DISPLAY' SHEET COLUMN B ROW I TO '' ");
Row row = displaySheet.createRow(0);
Cell cell = row.createCell(0);
cell.setCellValue("TEST");
} else if (recipeCellValueColumnB.equals("NO")) {
System.out.println("PUT VALUE FROM 'TO FORMAT' COLUMN A ROW I INTO 'DISPLAY' SHEET CELL COLUMN B ROW I");
System.out.println("PUT VALUE FROM 'RECIPE STEPS' COLUMN A ROW I INTO 'DISPLAY' SHEET CELL COLUMN A ROW I");
Row row = displaySheet.createRow(0);
Cell cell = row.createCell(0);
cell.setCellValue("TEST");
}else if (recipeCellValueColumnA.equals("Step Name") && recipeCellValueColumnB.equals("Always Compare?")) {
System.out.println("SET CELL IN DISPLAY COLUMN A ROW I TO 'REQUIRED STEPS'");
System.out.println("PUT VALUE FROM 'TO FORMAT' COLUMN A ROW I INTO 'DISPLAY' SHEET CELL COLUMN B ROW I");
Row row = displaySheet.createRow(0);
Cell cell = row.createCell(0);
cell.setCellValue("TEST");
}
}
FileOutputStream output_file = new FileOutputStream(new File("Change.xls"));
BufferedOutputStream bos = new BufferedOutputStream(output_file);
fWorkbook.write(output_file);
fWorkbook.close();
bos.close();
output_file.close();
}catch(Exception e){
}
}
Sorry for any poor explanation, it's late and I'm tired and frustrated!
Thanks

The problem with your code is this:
catch(Exception e)
{
}
This is saying "don't tell me about any exceptions". This is exception squashing ... and it is horrible, and lazy, and just plain wrong.
Somewhere in your code there is probably something that is either throwing an exception directly, or causing POI (or something) to throw an exception. That's a bug. But your horrible exception squashing is throwing away the evidence that will allow you to identify and then fix the bug.
I am guessing the problem is caused by the data formatter, but I can't work out why.
It could be many things ... including something daft like an NPE or a passing an out-of-range index of an incorrect filename.
Solution:
Get rid of the try catch, and allow the exceptions to propagate to the caller.
In the caller (or further up the stack) handle unexpected exceptions by printing or logging a stacktrace and causing the application to fail.
Run the modified program.
When it fails (at it probably will), read the exception message and stacktrace and work out what the underlying problem is; i.e the problam that your horrible exception squashing is hiding.
Then remember to NEVER squash all exceptions like that, in Java or in any other programming language.
(It is sometimes OK to squash a specific exception in a specific context ... but only after carefully analyzing the code to ensure that that you won't squash other (unexpected) exceptions at the same time.)

Apache POI blank values

I am using Apache POI to import data from excel file to database.(newbie to APACHE POI)
In which I am allowing user to select columns from excel sheet and Map those columns to the Database columns. After mapping the columns, when I try to insert the records from Excel to Database then:
If Columns with NO blank values in them are Mapped then Proper data is inserted into the database
If columns are Mapped with BLANK values in them, then if a Excel Cell has blank value then previous value of that column is assigned.
Source Code:
FileInputStream file = new FileInputStream(new File("C:/Temp.xls"));
HSSFWorkbook workbook = new HSSFWorkbook(file); //Get the workbook instance for XLS file
HSSFSheet sheet = workbook.getSheetAt(0); //Get first sheet from the workbook
Iterator<Row> rowIterator = sheet.iterator(); //Iterate through each rows from first sheet
while (rowIterator.hasNext())
{
HSSFRow hssfRow = (HSSFRow) rowIterator.next();
Iterator<Cell> iterator = hssfRow.cellIterator();
int current = 0, next = 1;
while (iterator.hasNext())
{
HSSFCell hssfCell = (HSSFCell) iterator.next();
current = hssfCell.getColumnIndex();
for(int i=0;i<arrIndex.length;i++) //arrayIndex is array of Excel cell Indexes selected by the user
{
if(arrIndex[i] == hssfCell.getColumnIndex())
{
if(current<next)
{
//System.out.println("Condition Satisfied");
}
else
{
System.out.println( "pstmt.setString("+next+",null);");
pstmt.setString(next,null);
next = next + 1;
}
System.out.println( "pstmt.setString("+next+","+((Object)hssfCell).toString()+");");
pstmt.setString(next,((Object)hssfCell).toString());
next = next + 1;
}
}
}
pstmt.addBatch();
}
I have look for similar questions on SO, but still not able to solve the issue.. So any help will be appreciated.
Thanks in advance..

You've made a very common mistake, which has been covered in rather a lot of past StackOverflow questions
As the Apache POI documentation on cell iterating says
In some cases, when iterating, you need full control over how missing or blank cells are treated, and you need to ensure you visit every cell and not just those defined in the file. (The CellIterator will only return the cells defined in the file, which is largely those with values or stylings, but it depends on Excel).
It sounds like you are in that situation, where you need to care about hitting every row/cell, and not just grabbing all the available cells without worrying about the gaps
You'll want to change you code to look somewhat like the example in the POI docs:
// Decide which rows to process
int rowStart = Math.min(15, sheet.getFirstRowNum());
int rowEnd = Math.max(1400, sheet.getLastRowNum());
for (int rowNum = rowStart; rowNum < rowEnd; rowNum++) {
Row r = sheet.getRow(rowNum);
int lastColumn = Math.max(r.getLastCellNum(), MY_MINIMUM_COLUMN_COUNT);
for (int cn = 0; cn < lastColumn; cn++) {
Cell c = r.getCell(cn, Row.RETURN_BLANK_AS_NULL);
if (c == null) {
// The spreadsheet is empty in this cell
// Mark it as blank in the database if needed
} else {
// Do something useful with the cell's contents
}
}
}