Java操作Excel?该如何处理

public List<Map<String, Object>> loadChitData(File excelFile,            boolean isDelete) throws BusinessException {        if (!excelFile.exists()) {            throw new BusinessException("要读取的文件不存在");        }        List<Map<String, Object>> chits = new ArrayList<Map<String, Object>>();        InputStream stream = null;        boolean errFlag = false;        try {            stream = new FileInputStream(excelFile);            Map<String, Integer> orgs = getOrgs(); // 所有部门            Workbook wb = null;            if(excelFile.getName().endsWith("xls")){                wb = new HSSFWorkbook(stream);   //读取2003            }else{                wb = new XSSFWorkbook(stream);    //读取2007            }            if (wb.getNumberOfSheets() == 0) {                throw new BusinessException("要导入的Excel文件中不存在数据");            }            Sheet sheet = wb.getSheetAt(0);                        Set<String> numSet = new HashSet<String>();            int rowIndex = 1;            boolean isNext = true;              while(isNext){                int lineNo = rowIndex+1;                Row row = sheet.getRow(rowIndex);                                Map<String, Object> chit = new HashMap<String, Object>();                if (row.getCell(0) == null || row.getCell(0).getStringCellValue().equals("")) {                    throw new BusinessException("导入的代金券第" + lineNo + "行名称为空");                } else {                    String name = row.getCell(0).getStringCellValue();                    chit.put("name", name);                }                                if (row.getCell(1) == null || row.getCell(1).getStringCellValue().equals("")) {                    throw new BusinessException("导入的代金券第" + lineNo + "行条码为空");                }else{                    String num = row.getCell(1).getStringCellValue();                    numSet.add(num);                    chit.put("num", num); // 代金券面值                }                                if (row.getCell(2) == null || row.getCell(2).getNumericCellValue() == 0.0) {                    throw new BusinessException("导入的代金券第" + lineNo + "行面值为空");                } else {                    String faceValue = row.getCell(2).getNumericCellValue()+"";                    BigDecimal DecFaceValue = new BigDecimal(faceValue);                    chit.put("faceValue", DecFaceValue);                }                // 所属部门编号                String orgName = row.getCell(3)!=null?row.getCell(3).getStringCellValue():"";                                if (orgs.containsKey(orgName)) {                    int orgId = orgs.get(orgName);                    chit.put("orgId", orgId);                } else {                    chit.put("orgId", null);                }                chit.put("orgName",orgName);                String indate = dateFormat(row.getCell(4).getDateCellValue());                if (indate == null) {                    throw new BusinessException("导入的代金券第" + lineNo + "行有效期为空");                } else {                                        chit.put("indate", indate);                }                String onsetDate = dateFormat(row.getCell(5).getDateCellValue());                if (onsetDate == null) {                    throw new BusinessException("导入的代金券第" + lineNo + "行生效时间为空");                } else {                                        chit.put("onsetDate", onsetDate);                }                chit.put("remark", row.getCell(6)!=null?row.getCell(6).getStringCellValue():"");                chits.add(chit);                rowIndex = rowIndex + 1;                row = sheet.getRow(rowIndex);                if(row == null){                    isNext = false;                    rowIndex = rowIndex - 1;                }            }            if (rowIndex > numSet.size()) {                throw new BusinessException("导入代金券条码不能重复");            }        } catch (BusinessException e) {            errFlag = true;            throw e;        } catch (Exception e) {            errFlag = true;            throw new BusinessException(e.getMessage());        }        finally {            if (isDelete || errFlag) {                // 关闭文件流                try {                    if (stream != null) {                        stream.close();                    }                } catch (IOException e) {                    e.printStackTrace();                }                excelFile.delete();            }        }        return chits;    }