Writing to an Excel File using Apache POI

Hi, I have a HashMap with some 3000 key value pairs and I want to print all the values of the HashMap to a Excel sheet. Can someone give me the complete code if you dont mind. Thank you.
vgsrikanthAsked:
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for_yanCommented:
This is your complete code, which puts three pairs form Hashmpa onto Excel Spreadsheet
You'll see

two b
one a
three c

in the to three rows of your excel file

Tested it with poi-3.7.jar

import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.*;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFDataFormat;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;

public class HSSFCreate {

	public static void main(String[] args) {
		try {

            HashMap<String, String> map = new HashMap<String, String>();
            map.put("one","a");
            map.put("two","b");
             map.put("three","c");

         //   Enumeration en = map.keys();

            Set<Map.Entry<String,String>> ss = map.entrySet();



			FileOutputStream fileOut = new FileOutputStream("poi-test.xls");
			HSSFWorkbook workbook = new HSSFWorkbook();
			HSSFSheet worksheet = workbook.createSheet("POI Worksheet");

			// index from 0,0... cell A1 is cell(0,0)

            int j = 0;
            for(Map.Entry<String,String> men : ss){

			HSSFRow row1 = worksheet.createRow((short) j);
                j++;

			HSSFCell cellA1 = row1.createCell((short) 0);
			cellA1.setCellValue(men.getKey());
			HSSFCellStyle cellStyle = workbook.createCellStyle();
			cellStyle.setFillForegroundColor(HSSFColor.GOLD.index);
			cellStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
			cellA1.setCellStyle(cellStyle);

			HSSFCell cellB1 = row1.createCell((short) 1);
			cellB1.setCellValue(men.getValue());
			cellStyle = workbook.createCellStyle();
			cellStyle.setFillForegroundColor(HSSFColor.LIGHT_CORNFLOWER_BLUE.index);
			cellStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);
			cellB1.setCellStyle(cellStyle);

			HSSFCell cellC1 = row1.createCell((short) 2);
			cellC1.setCellValue(true);

			HSSFCell cellD1 = row1.createCell((short) 3);
			cellD1.setCellValue(new Date());
			cellStyle = workbook.createCellStyle();
			cellStyle.setDataFormat(HSSFDataFormat
					.getBuiltinFormat("m/d/yy h:mm"));
			cellD1.setCellStyle(cellStyle);
            }

			workbook.write(fileOut);
			fileOut.flush();
			fileOut.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

}

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vgsrikanthAuthor Commented:
Thank you Yan for the solution.My concern is if I have to print 3000 values then do i have to create 3000 cells using createcell() function. If you dont mind can you give code to print 3000 values of HashMap.
0
for_yanCommented:
Don't worry, just remove the style - it is too much with style
with this code i wrote 3000 rows - two cell in each row - and without
any problems
 
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.*;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFDataFormat;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;

public class HSSFCreate {

	public static void main(String[] args) {
		try {

            HashMap<String, String> map = new HashMap<String, String>();
            map.put("one","a");
            map.put("two","b");
             map.put("three","c");

         //   Enumeration en = map.keys();

            Set<Map.Entry<String,String>> ss = map.entrySet();



			FileOutputStream fileOut = new FileOutputStream("poi-test.xls");
			HSSFWorkbook workbook = new HSSFWorkbook();
			HSSFSheet worksheet = workbook.createSheet("POI Worksheet");

			// index from 0,0... cell A1 is cell(0,0)

            int j = 0;
     

                    for(int jj=0; jj<3000; jj++){

			HSSFRow row1 = worksheet.createRow((short) jj);
                j++;

			HSSFCell cellA1 = row1.createCell((short) 0);
			cellA1.setCellValue("Heelo");


			HSSFCell cellB1 = row1.createCell((short) 1);
			cellB1.setCellValue("OK");
	

			HSSFCell cellC1 = row1.createCell((short) 2);
			cellC1.setCellValue(true);

			HSSFCell cellD1 = row1.createCell((short) 3);

            }

			workbook.write(fileOut);
			fileOut.flush();
			fileOut.close();
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}

	}

}

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