package demo;
import junit.framework.Test;
import junit.framework.TestCase;
import junit.framework.TestSuite;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
public class Readwrite {
public static void main(String[] args) throws Exception
{
//Get the excel file and create an input stream for excel
FileInputStream fis = new FileInputStream("D:\\Testing_Team\\Age_Validation.xlsx");
//load the input stream to a workbook object
//Use XSSF for (.xlsx) excel file and HSSF for (.xls) excel file
XSSFWorkbook wb = new XSSFWorkbook(fis);
//get the sheet from the workbook by index
XSSFSheet sheet = wb.getSheet("Age");
//Count the total number of rows present in the sheet
int rowcount = sheet.getLastRowNum();
System.out.println(" Total number of rows present in the sheet : "+rowcount);
//get column count present in the sheet
int colcount = sheet.getRow(1).getLastCellNum();
System.out.println(" Total number of columns present in the sheet : "+colcount);
//get the data from sheet by iterating through cells
//by using for loop
for(int i = 1; i<=rowcount; i++)
{
XSSFCell cell = sheet.getRow(i).getCell(1);
String celltext="";
//Get celltype values
if(cell.getCellType()==Cell.CELL_TYPE_STRING)
{
celltext=cell.getStringCellValue();
}
else if(cell.getCellType()==Cell.CELL_TYPE_NUMERIC)
{
celltext=String.valueOf(cell.getNumericCellValue());
}
else if(cell.getCellType()==Cell.CELL_TYPE_BLANK)
{
celltext="";
}
//Check the age and set the Cell value into excel
if(Double.parseDouble(celltext)>=18)
{
sheet.getRow(i).getCell(2).setCellValue("Major");
}
else
{
sheet.getRow(i).getCell(2).setCellValue("Minor");
}
}//End of for loop
//close the file input stream
fis.close();
//Open an excel to write the data into workbook
FileOutputStream fos = new FileOutputStream("D:\\Testing_Team\\Age_Validation.xlsx");
//Write into workbook
wb.write(fos);
//close fileoutstream
fos.close();
}
}
*Facing an issue as follows: [ Exception in thread "main" java.lang.NullPointerException at demo.Readwrite.main(Readwrite.java:31) ] . Can you provide some guidance on this matter?
I found this helpful video reference: https://www.youtube.com/watch?v=orYZB_RUgNc
I have included both poi-ooxml and poi dependencies.
Awaiting your valuable response.*