Java Apache POI Blank Cells

Question

I am new to Apache POI but not new to Java. I been trying to convert data from one excel file to another, changing any delimiter data to new cells. Although most of the new data is correct but a few exceptions are not following the rules for blank cells. Here is the input file https://ufile.io/bce15 and here is the output file https://ufile.io/55020

In the Image below record 4 and 5 are not playing by the rules, and i cant figure out why!!

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Iterator;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;


public class testWrite {
public static void main( String [] args ) {             
    int rowNums = 1;
    try {

        FileInputStream file = new FileInputStream(new      File("ExceptionDataDummy.xlsx"));;
        XSSFWorkbook wb = new XSSFWorkbook(file);
        XSSFSheet sheet = wb.getSheetAt(0);           
        String filename = "ExceptionDataResult.xlsx" ;
        XSSFWorkbook workbook = new XSSFWorkbook();
        XSSFSheet sheet1 = workbook.createSheet("FirstSheet");             
        Iterator<Row> rows = sheet.rowIterator();            
        int col = 0;
        while( rows.hasNext() ) {  
            XSSFRow row = (XSSFRow) rows.next();
            XSSFRow row1 = sheet1.createRow((short)rowNums);
            System.out.println("\n");
            Iterator<Cell> cells = row.cellIterator();
            while( cells.hasNext() ) {

                XSSFCell cell = (XSSFCell) cells.next();
                if(XSSFCell.CELL_TYPE_NUMERIC==cell.getCellType()) {                        
                    row1.createCell(col).setCellValue(cell.getNumericCellValue());
                    col++;                   
                }
                else
                if(XSSFCell.CELL_TYPE_STRING==cell.getCellType()){
                    String contents =  cell.getStringCellValue();
                    String[] items = contents.split(",");                       
                    for (String item : items) {                         
                        row1.createCell(col).setCellValue(item);
                        col++;                          
                    }
                }
                else
                    if(XSSFCell.CELL_TYPE_BOOLEAN==cell.getCellType()) {
                        row1.createCell(col).setCellValue(cell.getBooleanCellValue());
                        col++;                          
                    }
                    else
                        if((cell.equals("")) || (XSSFCell.CELL_TYPE_BLANK==cell.getCellType()) || (cell == null)) {

                            cell.setCellType(Cell.CELL_TYPE_BLANK);
                            col++;                              
                        }
                            else {                                  
                       System.out.print("Unknown cell type");
                            }
            }
            rowNums++;
            col=0;               
        }
        FileOutputStream fileOut = new FileOutputStream(filename);
        workbook.write(fileOut);
        fileOut.close();
        System.out.println("Your excel file has been generated!");
        wb.close();
        workbook.close();
    } catch ( IOException ex ) {
        ex.printStackTrace();
    }                   
}
}

Answer 1

In your code, you are using cellIterator

Iterator<Cell> cells = row.cellIterator();

cellIterator does not include cells which are null.

Instead of using cellIterator, you have to start loop from the first cell to the last cell and then check whether cell is null or not.

You can refer to below sample code -

for (int colNum = 0; colNum < row.getLastCellNum(); colNum++) {

   Cell cell = row.getCell(colNum, Row.CREATE_NULL_AS_BLANK);
   String cellValue = null;

// do whatever you want to do with the cell or its value

}