package test;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
 
import org.apache.poi.EncryptedDocumentException;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.WorkbookFactory;

public class ExcelFileUpdateExample1 {
	 
	 
    public static void main(String[] args) {
        String excelFilePath = "JavaBooks.xlsx";
         
        try {
            //FileInputStream inputStream = new FileInputStream(new File(excelFilePath));
            OPCPackage pkg = null;
    		try {
    			pkg = OPCPackage.open(new File(excelFilePath));//inputStream);
    		} catch (InvalidFormatException e) {
    			
    			e.printStackTrace();
    		}
            Workbook workbook = WorkbookFactory.create(pkg);//inputStream);
 
            Sheet sheet = workbook.getSheetAt(0);
 
            Object[][] bookData = {
                    {"The Passionate Programmer", "Chad Fowler", 16},
                    {"Software Craftmanship", "Pete McBreen", 26},
                    {"The Art of Agile Development", "James Shore", 32},
                    {"Continuous Delivery", "Jez Humble", 41},
            };
 
            int rowCount = sheet.getLastRowNum();
 
            for (Object[] aBook : bookData) {
                Row row = sheet.createRow(++rowCount);
 
                int columnCount = 0;
                 
                Cell cell = row.createCell(columnCount);
                cell.setCellValue(rowCount);
                 
                for (Object field : aBook) {
                    cell = row.createCell(++columnCount);
                    if (field instanceof String) {
                        cell.setCellValue((String) field);
                    } else if (field instanceof Integer) {
                        cell.setCellValue((Integer) field);
                    }
                }
 
            }
 
            //inputStream.close();
            pkg.close();
 
            FileOutputStream outputStream = new FileOutputStream("JavaBooks.xlsx");
            workbook.write(outputStream);
            workbook.close();
            outputStream.close();
            
             
        } catch (IOException | EncryptedDocumentException ex) {
            ex.printStackTrace();
        }
    }
 
}