public void creaExcelElencoAdcEmail(Iterator<ExportExcel> iter, int righeTotali)  throws Exception
    {
        HSSFSheet sheet = wb.getSheetAt(0);
        int rowNum = 2;
        while(iter.hasNext())
        {
            ExportExcel istanza = iter.next();
            HSSFRow row = sheet.createRow(rowNum);
            int i=1;
            row.createCell(i++).setCellValue(istanza.getCodAssociazione());
            row.createCell(i++).setCellValue(istanza.getDescrizione());
            row.createCell(i++).setCellValue(istanza.getEmail());
            rowNum++;
        }
        for(int columnPosition = 1; columnPosition< 6; columnPosition++) {
            sheet.autoSizeColumn((short) (columnPosition));
        }

        wb.write(stream);

    }