How to keep track whether writing in a worksheet is finished?

[smhasan11]

Hi I'm reading a WorkBook using POI and then highlighting certain cells based on my calculation.
If my workbook has only one sheet then its work fine; but if there are multiple sheets then it gets screwed up. I'm doing something as follows:

for( each workBook){

  for(each workSheet){
    
     //do some calcualtion on the cells...
    
     highLightCells(workBook, workSheet, cellToHighLight)
  }
}


	private void highLightColumn(ExcelWorkBook workbook, ExcelWorkSheet workSheet, ExcelMaskingInfo maskingInfo){

		try{
			this.outputStream = new FileOutputStream(workbook.getFileName());

			String startPosition = maskingInfo.getStartPosition();
			ArrayList<Integer> startP = this.convertPosition(startPosition);

			String endPosition = maskingInfo.getEndPosition();
			ArrayList<Integer> endP = this.convertPosition(endPosition);

			// index=1 in both Lists(startP, endP) contain numeric digits of position.
			//eg: position = G23; startP.get(1) = 23

			//iterate through all rows after the columnHeaderRow
			for(int rowNum = startP.get(1); rowNum <= endP.get(1); rowNum++){			

				HSSFRow row = workSheet.getSheet().getRow(rowNum); // get the current row

				if (row == null) { // if any row is EMPTY, poi treats it as null
					continue;
				}

				// get the specific column
				HSSFCell cell = row.getCell(startP.get(0));

				if (cell == null) { 
					continue;
				}
				else{
					//System.out.println("cellValue="+cell.getStringCellValue());
					HSSFCellStyle cellStyle = cell.getCellStyle();
					
					//create and set a new font for this cell
					cellStyle.setFont(this.getCamoFont(workbook.getExcelWorkBook()));
					
					cellStyle.setFillForegroundColor(IndexedColors.LIGHT_GREEN.getIndex());
					cellStyle.setFillPattern(CellStyle.SOLID_FOREGROUND);

				}

			}	

			// write back to the workBook	
			workSheet.getSheet().getWorkbook().write(this.outputStream);
			outputStream.flush();
			outputStream.close();
		}
		catch (Exception e) {
			e.printStackTrace();
		}

	}

Now, lets say, I've 2 sheets in a workbook
in "sheet1"- column-A, column-D and column -F should be highlighted. and in "sheet2" only column -C should be highlighted...
But my program highlights column -F in sheet2 as well.

I guess, when POI is writing back to the worksheet, I need to some how keep track whether its finished before it goes to the next sheet.
Am I correct to say that? Or what else might be the reason?
Any comments, how can I do that?

[smhasan11]

* Modifying current cell's CellStyle effects other cell for no good reason...
* After trying and banging my heads for all day,
* I found the following comments in <a> Busy Developers' Guide to HSSF and XSSF Features </a>
*
* "
It is important to create a new cell style from the workbook otherwise you can end up
modifying the built in style and effecting not only this cell but other cells.
"

[Tolls]

That's about right.
The recommendation, which you just quoted, is to create a new style and apply it to the cell.
It also says to reuse styles...that is, don't create the same style multiple times because Excel won't like that. I think it has a style limit.
I've fallen foul of that latter one before now.