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How to get the usedrange of sheet without VBA?

I use groovy script to works with excel file. And I use POI API to manipulate those files. But in the documentation there is no methods or object that help me to find a way to get the used range of a sheet. I tried to calculate it by my own using methods like getLastRowNum() or getPhysicalNumberOfRows() but none of them works well because they stop counting when they meet an empty rows. Sometimes excel file can have empty rows and after those empty rows they could be filled rows, but those methods just STOP when they just meet one empty rows. So those function will not help me to reach my goal.
So I try another solution. I want to create a named range in the workbook by using the methods createName() then make a named range with a formula that return the usedrange of the actual sheet. But I don't know how to make it, I searched a lot and all I found is about VBA, I don't want to use it because in named range formula we can't use VBA. I found a function call GET.WORKBOOK and I think this could a good start point to search an answer about my problem. This function return the list of worksheet name of the workbook. There no link between my problem and this result but I think that GET object could contain more method like GET.WORKSHEET it's very speculative but I think there is more than just GET.WORKBOOK. (If you have any informations about this, even if it's not solve my problem please put this in the comment please, I'm really interested in this GET function.)
NB : If you find a way to solve my problem with a groovy-only solution I would be very happy too. I didn't recall this type of solution because I search a lot in this direction but I didn't found anything to help me.
NB2 : I adding java tag because groovy and java are very close. And I think someone that can found a solution in java for this problem could do the same in groovy.
NB3 : I want a cell reference like A1:B2 to specify the used range
NB4 : I re-test the methods getLastRowNum() and it worked perfectly, I made some mistakes in my code that's why it didn't work well. Now here's my new problem, when I use this method I cannot access to a cell that empty with the getCell methods. Here's my code :
import org.apache.poi.ss.usermodel.WorkbookFactory;
wb = WorkbookFactory.create(new File("./webapps/etlserver/data/files/test_ws.xlsx"));
def getUsedRangeByIndex(file_path,ind_ws){
wb = WorkbookFactory.create(new File(file_path));
max_col = 0;
for(int i = 0 ; i < wb.getSheetAt(ind_ws).getLastRowNum() ; i++){
LOG.info(i.toString())
if(wb.getSheetAt(ind_ws).getRow(i) != null && wb.getSheetAt(ind_ws).getRow(i).getLastCellNum() > max_col){
max_col = wb.getSheetAt(ind_ws).getRow(i).getLastCellNum();
}
}
return "A1:" + wb.getSheetAt(ind_ws).getRow(wb.getSheetAt(ind_ws).getLastRowNum()).getCell(max_col, RETURN_NULL_AND_BLANK).getReference()
}
LOG.info(getUsedRangeByIndex("./webapps/etlserver/data/files/test_ws.xlsx",0))
I know I have to improve it with some code that calculate the first used cell but for now I will consider A1 as the first used cell.

If the definition of the used range of a worksheet is as follows: ...
The used range is the cell range from first used top left cell to last used bottom right cell.
... and the used Apache POI version is one of the current ones (me using apache poi 5.2.2) , then the simplest approach to get that used range is usig following methods:
Sheet.getFirstRowNum and Sheet.getLastRowNum to get first used row and last used row in sheet. If one of this return -1 then the sheet does not contain any rows and so does not have a used range.
Then loop over all rows between first used row and last used row and get Row.getFirstCellNum and Row.getLastCellNum. Note the API doc of Row.getLastCellNum : Gets the index of the last cell contained in this row PLUS ONE. If the found first column in that row is lower than before found first columns, then this is the new first column. If the found last column in that row is greater than before found last columns, then this is the new last column.
After that we have first used row, last used row, leftmost used colum and rightmost used column. That is the used range then.
Complete example:
import java.io.FileInputStream;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;
class ExcelGetSheetUsedRange {
/**
* Simplest method to get the used range from a sheet.
*
* #param sheet The sheet to get the used range from.
+ #return CellRangeAddress representing the used range or null for an empty sheet.
*/
static CellRangeAddress getUsedRange(Sheet sheet) {
int firstRow = sheet.getFirstRowNum();
if (firstRow == -1) return null;
int lastRow = sheet.getLastRowNum();
if (lastRow == -1) return null;
int firstCol = Integer.MAX_VALUE;
int lastCol = -1;
for (int r = firstRow; r <= lastRow; r++) {
Row row = sheet.getRow(r);
if (row != null) {
int thisRowFirstCol = row.getFirstCellNum();
int thisRowLastCol = row.getLastCellNum()-1; // see API doc Row.getLastCellNum : Gets the index of the last cell contained in this row PLUS ONE.
if (thisRowFirstCol < firstCol) firstCol = thisRowFirstCol;
if (thisRowLastCol > lastCol) lastCol = thisRowLastCol;
}
}
if (firstCol == Integer.MAX_VALUE) return null;
if (lastCol == -1) return null;
return new CellRangeAddress(firstRow, lastRow, firstCol, lastCol);
}
public static void main(String[] args) throws Exception {
//Workbook workbook = WorkbookFactory.create(new FileInputStream("./template.xls"));
Workbook workbook = WorkbookFactory.create(new FileInputStream("./template.xlsx"));
Sheet sheet = workbook.getSheetAt(0);
CellRangeAddress usedRange = getUsedRange(sheet);
System.out.println(usedRange);
}
}
As told in API doc of Sheet.getLastRowNum:
Note: rows which had content before and were set to empty later might
still be counted as rows by Excel and Apache POI...
But that is a problem of Excel wich also may occur when get the used range via Worksheet.UsedRange property.

The solution of Axel Richter is perfect. But here's a pre-build code you can directly insert into a jedox job to makes things work well. It a kind of translation from java to groovy. Here's the code :
import org.apache.poi.ss.usermodel.WorkbookFactory;
import org.apache.poi.ss.util.CellRangeAddress;
wb = WorkbookFactory.create(new File("./webapps/etlserver/data/files/test_ws.xlsx"));
sheet = wb.getSheetAt(0);
def getUsedRange(sheet) {
firstRow = sheet.getFirstRowNum();
if (firstRow == -1) return null;
lastRow = sheet.getLastRowNum();
if (lastRow == -1) return null;
firstCol = Integer.MAX_VALUE;
lastCol = -1;
for (int r = firstRow; r <= lastRow; r++) {
row = sheet.getRow(r);
if (row != null) {
thisRowFirstCol = row.getFirstCellNum();
thisRowLastCol = row.getLastCellNum()-1;
if (thisRowFirstCol < firstCol) firstCol = thisRowFirstCol;
if (thisRowLastCol > lastCol) lastCol = thisRowLastCol;
}
}
if (firstCol == Integer.MAX_VALUE) return null;
if (lastCol == -1) return null;
return (new CellRangeAddress(firstRow, lastRow, firstCol, lastCol)).formatAsString();
}
LOG.info(getUsedRange(sheet));

how to get the next cell in the same row when using poi

I am using poi(v4.0.0) to import the excel document. But when I tried to get the next cell carModelCell, it always return null, this is my Java 8 code looks like:
public void verifyCar(Cell cell, int relativeRowIndex, Head head) {
if (cell.getRowIndex() > 0 && head.getFieldName().equals("car")) {
if (StringUtils.isBlank(cell.getStringCellValue())|| cell.getStringCellValue().equals("无车")) {
return;
}
Cell carModelCell = cell.getRow().getCell(cell.getColumnIndex() + 1);
if (carModelCell == null || StringUtils.isBlank(carModelCell.getStringCellValue())) {
SparkUserParseResult result = new SparkUserParseResult();
result.setSuccess(false);
UploadSparkUserDataListener.parseSuccess.set(result);
return;
}
}
}
I am tried to get row from Cell, and get the next cell value with the same row and do some check, but the next cell carModelCell always return null. I have already sure the next cell of current row have a value. why would this happen? what should I do to fix this problem? This code block was in CellStyleWriteHandler which extend AbstractCellStyleStrategy in easy excel (version 2.2.11):
public class CellStyleWriteHandler extends AbstractCellStyleStrategy {
#Override
protected void setContentCellStyle(Cell cell, Head head, Integer relativeRowIndex) {
impl(cell, head, relativeRowIndex);
}
}
I tried to get the last index num was 14, the current column index number was 13. the total column of my imported excel was 24, seems the easy excel did not pass the full column, is it possible to fix this problem? How to get the next cell of current row?

i also user poi to parse excel, i think problem in this line:
Cell carModelCell = cell.getRow().getCell(cell.getColumnIndex() + 1);
code above is error, becase cell can get from row,like:
Cell cell = sheetColumnRow.getRow()
one raw can cantain many Cell，but you can not get complete row from Cell, Parse row Cell value can not reverse; wish help you;

Apache POI getStringCellValue() printing null

I'm getting a weird error while trying to read the Cell values through Apache POI in java:
System.out.println(row.getCell(13, Row.CREATE_NULL_AS_BLANK).getStringCellValue())
is always printing null, even after specifying the Missing policy as Row.CREATE_NULL_AS_BLANK.My writing logic to the Cell is :
public void writeCell( String value, Sheet sheet, int rowNum, int colNum)
{
Row row = sheet.getRow(rowNum);
if (row == null)
{
row = sheet.createRow(rowNum);
}
Cell cell = row.createCell(colNum, Cell.CELL_TYPE_STRING);
if (value == null)
{
return;
}
cell.setCellValue(value);
}
When I'm writing to Cell at colNum = 13 , the String value object is null. I'm not able to sort out this issue.

This line doesn't do what you seem to think it does:
System.out.println(row.getCell(13, Row.CREATE_NULL_AS_BLANK).getStringCellValue())
In effect, that's doing
Cell cell = row.getCell(13);
if (cell == null) { cell = row.createCell(13, Cell.CELL_TYPE_BLANK); }
So, if there is nothing in that cell, it creates it as an empty blank one
Then, you try doing:
cell.getStringCellValue()
This only works for String cells, and in the missing case you've told POI to give you a Blank new cell!
If you really just want a string value of a cell, use DataFormatter.formatCellValue(Cell) - that returns a String representation of your cell including formatting. Otherwise, check the type of your cell before trying to fetch the value!

The getStringCellValue() on the Cell interface would return "" if your code worked as supposed (setting the call blank).
Is it not possible that value for col id 13 is not null but "null"?

POI says Cell is empty but cell has a value

I'm opening a Excel (xls) file in my Java Application with POI.
There are 30 Lines in this Excelfile.
I need to get the Value at ColumnIndex 9.
My code:
Workbook wb;
wb = WorkbookFactory.create(inp);
Sheet sheet = wb.getSheetAt(0);
for (Row row : sheet) {
if (row.getLastCellNum() >= 6) {
for (Cell cell : row) {
if(cell.getColumnIndex == 9) {
//do something
}
}
}
}
Every Row in Excel has Values in Columns 1-14.
My problem is, only some Values are recognized. I wrote the same value in every cell in ColumnIndex 9 (10th Column in my Excel sheet), but the Problem is still the same.
What could cause this problem?

Make sure you set the same Date format for all cells in column (select column and set format explicity) And i belive using DataUtil class to get data is more appropriate, than call cell.getDateCellValue().

POI uses 0 based counting for columns. So, if you want the 9th Column, you need to fetch the cell with index 8, not 9. It looks like you're checking for column with index 9, so are one column out.
If you're not sure about 0 based indexing, then the safest thing is to use the CellReference class to help you. This will translate between Excel style references, eg A1, and POI style 0-based offsets eg 0,0. Use something like:
CellReference ref = new CellReference("I10");
Row r = sheet.getRow(ref.getRow());
if (r == null) {
// That row is empty
} else {
Cell c = r.getCell(ref.getCol());
// c is now the cell at I10
}

Seems to be a Problem with the excel document(s).
Converting them to csv and then back to xls solves the problem.

Empty cells issue when extracting excel data using POI in JAVA?

I have just Extracted the cells from the excel sheet using Apache POI, everything is working fine. But whenever there is an empty cell, the very next right cell data is what I get as a output. But, if exists a value in the latter, the desired output is coming.
This is the logic I've written.
Iterator<Row> rowIterator=sheet.rowIterator();
while(rowIterator.hasNext())
{
ExtractedRowsString extRows=new ExtractedRowsString();
ArrayList<HSSFCell> list=new ArrayList<HSSFCell>();
HSSFRow row=(HSSFRow) rowIterator.next();
Iterator<Cell> cellIterator=row.cellIterator();
while(cellIterator.hasNext())
{
HSSFCell cell=(HSSFCell)cellIterator.next();
list.add(cell);
}
if(check)
{
addBean(list,extRows);
print(extRows);
}
check=true;
}
What may be the problem?
EDITED :
public static void addBean(ArrayList list,ExtractedRowsString extRows)
{
for(int i=0;i<list.size();i++)
{
switch(i)
{
case 0:
extRows.setSchool_success_id((list.get(i)).toString());
break;
case 1:
extRows.setPem_id( (list.get(i)).toString() );
break;
case 2:
extRows.setDistrict_code((list.get(i)).toString());
break;
case 3:
extRows.setDistrict((list.get(i)).toString());
break;
}
}
}

From the docs:
cellIterator
public java.util.Iterator cellIterator()
Specified by:
cellIterator in interface Row
Returns:
cell iterator of the physically
defined cells. Note that the 4th
element might well not be cell 4, as
the iterator will not return
un-defined (null) cells. Call
getCellNum() on the returned cells to
know which cell they are. As this only
ever works on physically defined
cells, the Row.MissingCellPolicy has
no effect.
In short, empty cells do not show up in the iterator so you always have to check which cell you got.

ArrayList does permit adding nulls. Also what is the addBean method doing (skipping nulls or empty strings perhaps?) Can you post a small working code that one can run ?