import java.io.*;
import org.apache.poi.hssf.usermodel.*;
import org.apache.poi.hssf.usermodel.HSSFRow;
class setDataFormat
	{
public static void main(String s[])
	{
      try{
      FileOutputStream out = new FileOutputStream("dateFormat.xls");
      HSSFWorkbook hssfworkbook = new HSSFWorkbook();
      HSSFSheet sheet = hssfworkbook.createSheet("new sheet");
      HSSFCellStyle cs = hssfworkbook.createCellStyle();
      HSSFDataFormat df = hssfworkbook.createDataFormat();
      cs.setDataFormat(df.getFormat("#,##0.0"));
      HSSFRow row = sheet.createRow((short)0);
      HSSFCell cell = row.createCell((short)0);
      cell.setCellValue(11111.1);
      cell.setCellStyle(cs);
      hssfworkbook.write(out);
      out.close();
       }catch(Exception e){}
 }
}