poi开源jar包操作excel时读取单元格的标准方法

public static Object getCellValue(HSSFCell cell){//参数可以包括int rowIndex, int cellnum if(cell == null){ return null;     }else if(cell.getCellType() == XSSFCell.CELL_TYPE_BLANK){       //System.out.println("第"+(rowIndex+1)+"行，第"+(cellnum+1)+"列  cellType为：CELL_TYPE_BLANK");     return null;    }else if(cell.getCellType() == XSSFCell.CELL_TYPE_STRING){       //System.out.println("第"+(rowIndex+1)+"行，第"+(cellnum+1)+"列  cellType为：CELL_TYPE_STRING  值为："+cell.getRichStringCellValue().getString());     return cell.getRichStringCellValue().getString();    }else if(cell.getCellType() == XSSFCell.CELL_TYPE_NUMERIC){             if(HSSFDateUtil.isCellDateFormatted(cell)){                 Date date = cell.getDateCellValue();             SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");             //System.out.println("第"+(rowIndex+1)+"行，第"+(cellnum+1)+"列  cellType为：Date 值为："+dateFormat.format(date));             return dateFormat.format(date);        }else{                 //System.out.println("第"+(rowIndex+1)+"行，第"+(cellnum+1)+"列  cellType为：CELL_TYPE_NUMERIC  值为："+cell.getNumericCellValue());         return cell.getNumericCellValue();        }           }else if(cell.getCellType() == XSSFCell.CELL_TYPE_BOOLEAN){     //System.out.println("第"+(rowIndex+1)+"行，第"+(cellnum+1)+"列  cellType为：CELL_TYPE_BOOLEAN  值为："+cell.getBooleanCellValue());     return cell.getBooleanCellValue();    }else if(cell.getCellType() == XSSFCell.CELL_TYPE_FORMULA){     //System.out.println("第"+(rowIndex+1)+"行，第"+(cellnum+1)+"列  cellType为：CELL_TYPE_FORMULA  值为："+cell.getNumericCellValue()+" 公式为："+cell.getCellFormula());    return cell.getNumericCellValue();    }else    return null;}