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Aspose Cells for Java: get original CSV row

I am using Aspose to read a CSV file.
I do not beforehand know the number of cells for each row of the file, but I will need to know it for further processing.
Unfortunately, I see no way to find out the number of cells in a CSV row.
Imagine the following row in the CSV file. It contains 7 cells, 4 of which are empty:
1,2,,4,,,
Using
row.iterator();
Aspose will only return 3 cells, as it ignores all empty cells.
As an alternative, I now do the following:
Cell lastCell = row.getLastCell();
int count = 0;
do {
cell = row.getCellOrNull(count);
String cellValue = cell == null ? "" : cell.getStringValueWithoutFormat();
//do something with the cell value...
count++;
} while (cell == null || ! lastCell.equals(cell));
This works better, as it returns the first 4 cells.
However, it still ignores the last 3 cells .
Is there any way to get information about the missing cells?
(It would be sufficient for me if Aspose could return the original Row as a String - I could then count the number of commas and find out the number of cells this way)

You may use Worksheet.getCells().getMaxDisplayRange() method to get the maximum display range.
Please consider this CSV. If you open it in MS-Excel and check the last cell, you will find it is Q2
Book1.csv
2,,,,1,,,,,,,,,,,,,
,,3,,,,
Aspose.Cells returns the same via the following code.
TxtLoadOptions opts = new TxtLoadOptions(LoadFormat.CSV);
Workbook wb = new Workbook("Book1.csv", opts);
Worksheet ws = wb.getWorksheets().get(0);
Range rng = ws.getCells().getMaxDisplayRange();
System.out.println(rng);
Here is the console output of the code.
Console Output
Aspose.Cells.Range [ Sheet1!A1:Q2 ]
Note: I am working as Developer Evangelist at Aspose

Apache POI : Why data is not properly inserted?

I want to insert a string to a Matrix of Cells in Excel, Using Apache POI, Here is the code :
for (int j=0;j<13;j++){
for(int i=6;i<30;i++)
{
XSSFRow row=sheet6.createRow(i);
cell0=row.createCell(j);
cell0.setCellValue("SampleRules_CI_01");
}
}
After executing my program, I get the column j=12 correctly filled, but the other columns (from 0 to 11) are still empty

You are replacing the row each time you get back around to the same value of i, when you call the createRow method. This has the effect of erasing whatever was on that row already, and only the last column doesn't get erased this way.
First, inside your i for loop, call the getRow method to see if it already exists. If it returns null, then the row doesn't exist yet and then you can call createRow.
XSSFRow row = sheet6.getRow(i);
if (row == null)
{
row = sheet6.createRow(i);
}

Writing to a particular cell location using Apache POI Excel

If I've got an list of parameters 'x,y,z' that aren't sorted, is there a straightforward way to write them to particular cells in an excel document created with POI, as though the first two parameters are X and Y coordinates?
For example, I have rows like:
10,4,100
Is it possible to write the value '100' in the cell at the 10th row, 4th column?
Looking at the documentation, it looks straightforward to iterate values into the next row, but I can't see any way of creating a fixed number of rows and columns and writing particular values to only certain cells.
Any advice or suggestions would be appreciated, thanks!

Sure, it's very easy, just remember that POI is 0 based not 1 based in addressing. Assuming you want to write to the 10th row, 4th column, you'd do something like
Row r = sheet.getRow(9); // 10-1
if (r == null) {
// First cell in the row, create
r = sheet.createRow(9);
}
Cell c = r.getCell(3); // 4-1
if (c == null) {
// New cell
c = r.createCell(3, Cell.CELL_TYPE_NUMERIC);
}
c.setCellValue(100);

Apache POI rows number

I am using Apache POI java and want to get the total number of rows which are not empty. I successfully processed a whole row with all its columns. Now I am assuming that I get an excel sheet with multiple rows and not a single row...so how to go about that? I was thinking of getting total number of rows (int n) and then loop until i<=n but not sure.
Suggestions are most welcome :)
Note: Apache POI version is 3.8. I am not dealing with Xlsx format...only xls.
Yes I tried this code but got 20 in return....which is not possible given I have only 5 rows
FileInputStream fileInputStream = new FileInputStream("COD.xls");
HSSFWorkbook workbook = new HSSFWorkbook(fileInputStream);
HSSFSheet worksheet = workbook.getSheet("COD");
HSSFRow row1 = worksheet.getRow(3);
Iterator rows = worksheet.rowIterator();
int noOfRows = 0;
while( rows.hasNext() ) {
HSSFRow row = (HSSFRow) rows.next();
noOfRows++;
}
System.out.println("Number of Rows: " + noOfRows);

for (int i = 0; i <= sheet.getLastRowNum(); i++) {
if ((tempRow = sheet.getRow(i)) != null) {
//Your Code Here
}
}

The problem is that POI considers empty rows as physical rows. This happens at times in Excel and while they are not visible to the eye, the rows certainly exist.
If you were to open you Excel sheet and select everything below your data, then delete it (i know it is empty looking, but do it anyway), POI will return the right number.

You may want to getPhysicalNumberOfRows() other than getLastRowNum()?

You can iterate over the rows which are not empty using this:
Iterator<Row> rowIterator = sheet.rowIterator();
while (rowIterator.hasNext()) {
Row row = (Row) rowIterator.next();
// Your code here
}
Thanks

worksheet.getLastRownNum() // *base index 0*
This method will give you the last row number where you might have fill the row, even if you have filled 5 rows, there can be cases that you might have filled some spaces in the remaining 15 rows or at the 21st row because of which it is giving last row number as 20.
There can be the cases that in every 5th row you enters data (starting from 1), then your 5th entry will be in 21st row, so again, if you use this method, you will get 20 in result.

Creating a dynamic 2D matrix in Java

I want a dynamic matrix, number rows and columns unkonw, filling it by clicking on a button. Bu there is more: I don't want to add entire rows, but just one cell at the time, one click = one cell added. Of course not randomly : 1st cell of 1st row, 2nd cell of 1st row... and then the same of the 2nd row and so one...
I know about UJMP, ArrayList, but it's not quite what I'm looking for. Please be accurate on your answer, thank you in advance.

Use this:
List<List<Integer>> dynamicMatrix = new ArrayList<List<Integer>>();
dynamicMatrix.add(new ArrayList<Integer>());
dynamicMatrix.add(new ArrayList<Integer>());
dynamicMatrix.add(new ArrayList<Integer>());
dynamicMatrix.get(0).add(6);
dynamicMatrix.get(0).add(7);
dynamicMatrix.get(0).add(8);
System.out.println(dynamicMatrix.get(0).get(0)); // 6
System.out.println(dynamicMatrix.get(0).get(1)); // 7
System.out.println(dynamicMatrix.get(0).get(2)); // 8