Create Excel file in java using PoI

package com.howto;

import java.io.File;
import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;

/*
 * Here we will learn how to create Excel file and header for the same.
 */
public class CreateExcelFile {

	int rownum = 0;
	HSSFSheet firstSheet;
	Collection<File> files;
	HSSFWorkbook workbook;
	File exactFile;

	{
		workbook = new HSSFWorkbook();
		firstSheet = workbook.createSheet("FIRST SHEET");
		Row headerRow = firstSheet.createRow(rownum);
		headerRow.setHeightInPoints(40);
	}

	public static void main(String args[]) throws Exception {

		List<String> headerRow = new ArrayList<String>();
		headerRow.add("Employee No");
		headerRow.add("Employee Name");
		headerRow.add("Employee Address");

		List<String> firstRow = new ArrayList<String>();
		firstRow.add("1111");
		firstRow.add("Gautam");
		firstRow.add("India");

		List<List> recordToAdd = new ArrayList<List>();
		recordToAdd.add(headerRow);
		recordToAdd.add(firstRow);

		CreateExcelFile cls = new CreateExcelFile(recordToAdd);
		cls.createExcelFile();
	}

	void createExcelFile(){
		FileOutputStream fos = null;
		try {
			fos=new FileOutputStream(new File("ExcelSheet.xls"));
			HSSFCellStyle hsfstyle=workbook.createCellStyle();
			hsfstyle.setBorderBottom((short) 1);
			hsfstyle.setFillBackgroundColor((short)245);
			workbook.write(fos);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	 CreateExcelFile(List<List> l1) throws Exception {

		try {

			for (int j = 0; j < l1.size(); j++) {
				Row row = firstSheet.createRow(rownum);
				List<String> l2= l1.get(j);

				for(int k=0; k<l2.size(); k++)
				{
					Cell cell = row.createCell(k);
					cell.setCellValue(l2.get(k));
				}
				rownum++;
			}

		} catch (Exception e) {
			e.printStackTrace();
		} finally {
		}

	}
}

 

PoI Jar will be required. Jar can be downloaded from Apache website.

 

7 Comments Create Excel file in java using PoI

    1. admin

      Hi Ramayu,

      CreateExcelFile is the name of class in which this main method is defined. Please look at the Public class name.

      Thanks

      Reply
  1. Mac

    I get this error when trying to compile..
    error: invalid method declaration; return type required
    CreateExcelFile(List l1) throws Exception {

    Reply
  2. Sirish

    How to add multiple rows using this program. I see the first row but if I want to add following rows with data how to do that. Thank You.

    Reply
  3. Richa

    what to do if i want to add extra sheet to this already created sheet dynamically? Such as if one sheet gets filled it will automatically add another sheet?

    Reply

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