POI对Excel自定义日期格式的读取(实例代码)

private List<String[]> rosolveFile(InputStream is, String suffix,       int startRow) throws IOException, FileNotFoundException {     Workbook xssfWorkbook = null;     if ("xls".equals(suffix)) {       xssfWorkbook = new HSSFWorkbook(is);     } else if ("xlsx".equals(suffix)) {       xssfWorkbook = new XSSFWorkbook(is);     }     Sheet xssfSheet = xssfWorkbook.getSheetAt(0);     if (xssfSheet == null) {       return null;     }     ArrayList<String[]> list = new ArrayList<String[]>();     int lastRowNum = xssfSheet.getLastRowNum();     for (int rowNum = startRow; rowNum <= lastRowNum; rowNum++) {       if (xssfSheet.getRow(rowNum) != null) {         Row xssfRow = xssfSheet.getRow(rowNum);         short firstCellNum = xssfRow.getFirstCellNum();         short lastCellNum = xssfRow.getLastCellNum();         if (firstCellNum != lastCellNum) {           String[] values = new String[lastCellNum];           for (int cellNum = firstCellNum; cellNum < lastCellNum; cellNum++) {             Cell xssfCell = xssfRow.getCell(cellNum);             if (xssfCell == null) {               values[cellNum] = "";             } else {               values[cellNum] = parseExcel(xssfCell);             }           }           list.add(values);         }       }     }     return list;   } 

private String parseExcel(Cell cell) {     String result = new String();     switch (cell.getCellType()) {     case HSSFCell.CELL_TYPE_NUMERIC:// 数字类型       if (HSSFDateUtil.isCellDateFormatted(cell)) {// 处理日期格式、时间格式         SimpleDateFormat sdf = null;         if (cell.getCellStyle().getDataFormat() == HSSFDataFormat             .getBuiltinFormat("h:mm")) {           sdf = new SimpleDateFormat("HH:mm");         } else {// 日期           sdf = new SimpleDateFormat("yyyy-MM-dd");         }         Date date = cell.getDateCellValue();         result = sdf.format(date);       } else if (cell.getCellStyle().getDataFormat() == 58) {         // 处理自定义日期格式：m月d日(通过判断单元格的格式id解决，id的值是58)         SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");         double value = cell.getNumericCellValue();         Date date = org.apache.poi.ss.usermodel.DateUtil             .getJavaDate(value);         result = sdf.format(date);       } else {         double value = cell.getNumericCellValue();         CellStyle style = cell.getCellStyle();         DecimalFormat format = new DecimalFormat();         String temp = style.getDataFormatString();         // 单元格设置成常规         if (temp.equals("General")) {           format.applyPattern("#");         }         result = format.format(value);       }       break;     case HSSFCell.CELL_TYPE_STRING:// String类型       result = cell.getRichStringCellValue().toString();       break;     case HSSFCell.CELL_TYPE_BLANK:       result = "";     default:       result = "";       break;     }     return result;   } 

//1、判断是否是数值格式 if(cell.getCellType() == HSSFCell.CELL_TYPE_NUMERIC){   short format = cell.getCellStyle().getDataFormat();   SimpleDateFormat sdf = null;   if(format == 14 || format == 31 || format == 57 || format == 58){     //日期     sdf = new SimpleDateFormat("yyyy-MM-dd");   }else if (format == 20 || format == 32) {     //时间     sdf = new SimpleDateFormat("HH:mm");   }   double value = cell.getNumericCellValue();   Date date = org.apache.poi.ss.usermodel.DateUtil.getJavaDate(value);   result = sdf.format(date); }