Java 导出Excel实例

@ResponseBody
   @RequestMapping(value = "export", method = RequestMethod.GET, produces = {"application/json;charset=UTF-8"})
   public void export(@RequestParam(value = "settleId", required = true) Integer settleId,
                         HttpServletResponse response) {
      String fileName = "export_" + BaseUtil.nowDateToStr() + ".xls";
      File f = new File(fileName);

      JSONArray paymentDetails;
      JSONObject settlement = new JSONObject();

      String[] fields = {"1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11"};
      BaseUtil.FieldTypes[] types = {BaseUtil.FieldTypes.STRINGTOSTRING, BaseUtil.FieldTypes.STRINGTOSTRING,
            BaseUtil.FieldTypes.UNCHANGE,BaseUtil.FieldTypes.UNCHANGE,BaseUtil.FieldTypes.UNCHANGE,
            BaseUtil.FieldTypes.STRINGTOSTRING,BaseUtil.FieldTypes.UNCHANGE,BaseUtil.FieldTypes.UNCHANGE,
            BaseUtil.FieldTypes.UNCHANGE,BaseUtil.FieldTypes.UNCHANGE,BaseUtil.FieldTypes.UNCHANGE,};
      try {
         paymentDetails = settlementService.exportSettlement(settlement, fields, types, settleId);
         //获取Excel所需的字段
         if (!f.exists()) {
            f.createNewFile();
         }

         String sourceFileName = this.getClass().getResource("/template").getPath() + "exportSettlement.xls";
         File sf = new File(sourceFileName);
         ExcelUtil.copyTo(sf, f);
         Workbook wb = ExcelUtil.openForWrite(fileName);
         Sheet sheet = wb.getSheetAt(0);
         if (wb != null) {
            //表头
            //Row 1
            String v;
            Row row = sheet.getRow(1);
            Cell cell = row.getCell(2);//organizationName
            v = settlement.getString("enrollBatch");
            cell.setCellValue(v);
            cell = row.getCell(7);//remittanceName
            v = settlement.getString("settlementName");
            cell.setCellValue(v);
            cell = row.getCell(12);
            v = settlement.getString("operator");
            cell.setCellValue(v);
//          //Row 2
            row = sheet.getRow(2);
            cell = row.getCell(2);//payBeginDate
            v = settlement.getString("studyCenterName");
            cell.setCellValue(v);
            cell = row.getCell(7);
            v = settlement.getString("settleDate");
            cell.setCellValue(v);
            cell = row.getCell(12);
            v = settlement.getString("auditor");
            cell.setCellValue(v);
//
//          //Row 3
            row = sheet.getRow(3);
            cell = row.getCell(2);
            v = settlement.getString("paySchoolYear");
            cell.setCellValue(v);
            cell = row.getCell(7);
            v = settlement.getString("remitBeginDate");
            cell.setCellValue(v);

            //Row 4
            row = sheet.getRow(4);
            cell = row.getCell(2);
            v = settlement.getString("projectType");
            cell.setCellValue(v);
            cell = row.getCell(7);
            v = settlement.getString("remitEndDate");
            cell.setCellValue(v);

            //Row 5
            row = sheet.getRow(5);
            cell = row.getCell(2);
            v = settlement.getString("serialNumber");
            cell.setCellValue(v);

            //缴费详情

            if (paymentDetails != null) {
               for (int i = 0; i < paymentDetails.size(); i++) {
                  JSONObject jo = paymentDetails.getJSONObject(i);
                  row = sheet.createRow(i + 7);
                  ExcelUtil.writeRow(wb, row, jo, fields);
               }
            }
         }
         ExcelUtil.saveAsNewFile(fileName, wb);
         String contentType = "application/vnd.ms-excel;charset=utf-8";
         DownloadUtil.download(response, f, contentType, new String(f.getName().getBytes("UTF-8")));
      } catch (Exception e) {
         logger.error("打款单下载报错", e);
      } finally {
         try {
            if (f != null) {
               f.delete();
            }
         } catch (Exception e) {
            e.printStackTrace();
         }
      }
   }

//sql语句

StringBuffer sql = new StringBuffer(
      "select s.student_name, s.identity_card, p.pay_school_year, p.pay_tuition, sum(p.pay_money) as pay_money, e.student_source, sum(p.channel_deduct) as channel_deduct, cpr.current_percentage, ((p.pay_tuition - sum(case when p.discount_type = '高校优惠' then p.discount_money else 0 end)) * current_percentage / 100) as channel_amount, 0 as channel_payback, ((sum(p.pay_money) - sum(case when p.discount_type = '中心优惠' then p.discount_money else 0 end)) * current_percentage / 100 - sum(p.channel_deduct)) as channel_need_payback, sum(case when p.discount_type = '高校优惠' then p.discount_money else 0 end) as discount_money");
sql.append(" from student s left join student_enroll e on s.student_id = e.student_id left join payment_detail p on s.student_id = p.student_id left join channel_protocol cp on s.channel_id = cp.channel_id left join channel_protocol_reward cpr on cp.protocol_id = cpr.channel_protocol_id");
sql.append(" where p.settlement_id = " + settleId);
sql.append(" group by s.student_name, s.identity_card, p.pay_school_year, p.pay_tuition, e.student_source, cpr.current_percentage");
List resultList = settlementDao.findBySql(sql.toString());

return  BaseUtil.convertSqlResultToJson(fields,types,resultList);

//转化sql，拿到List集合

@Override
public List findBySql(String sql) {
   return getEntityManager().createNativeQuery(sql).getResultList();
}

//转换converSqlFieldToJson

public static JSONObject convertSqlFieldToJson(String[] keys,FieldTypes[] types,Object[] values) throws ParseException {
    JSONObject o = new JSONObject();
    for (int i = 0;i < keys.length;i++) {
        String key = keys[i];
        FieldTypes type;
        if(types == null){
            type = FieldTypes.UNCHANGE;
        } else {
            type = types[i];
        }
        SimpleDateFormat sdf = null;
        Object value = values[i];
        Date d = null;
        switch (type) {
            case INTEGERTOSTRING:
                if (value == null){
                    o.put(key,"");
                } else {
                    Integer iv = (Integer) value;
                    o.put(key, iv.toString());
                }
                break;
            case FLOATTOSTRING:
                if (value == null){
                    o.put(key,"");
                } else {
                    Float fv = (Float) value;
                    o.put(key, fv.toString());
                }
                break;
            case DATETOSTIRNGTIME:
                if (value == null){
                    o.put(key,"");
                } else {
                    sdf = new SimpleDateFormat("HH:mm:ss");
                    java.sql.Date qtv = (java.sql.Date) value;
                    d = new Date(qtv.getTime());
                    o.put(key, sdf.format(d));
                }
                break;
            case DATETOSTRINGDATE:
                if (value == null){
                    o.put(key,"");
                } else {
                    sdf = new SimpleDateFormat("yyyy-MM-dd");
                    java.sql.Date qdv = (java.sql.Date) value;
                    d = new Date(qdv.getTime());
                    o.put(key, sdf.format(d));
                }
                break;
            case DATETOSTRINGDATETIME:
                if (value == null){
                    o.put(key,"");
                } else {
                    sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                    java.sql.Date qdtv = (java.sql.Date) value;
                    d = new Date(qdtv.getTime());
                    o.put(key, sdf.format(d));
                }
                break;
            case STRINGTOTIMESTAMP:
            case STRINGTODATE:
                if (value == null){
                    o.put(key,null);
                } else {
                    sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                    String sdv = (String) value;
                    d = sdf.parse(sdv);
                    o.put(key, d);
                }                    break;
            case STRINGTOFLOAT:
                if (value == null){
                    o.put(key,null);
                } else {
                    String sfv = (String) value;
                    o.put(key, new Float(sfv));
                }
                break;
            case STRINGTOINTEGER:
                if (value == null){
                    o.put(key,null);
                } else {
                    String siv = (String) value;
                    o.put(key, new Integer(siv));
                }
                break;
            case DATETODATE:
                if (value == null){
                    o.put(key,null);
                } else {
                    java.sql.Date qd = (java.sql.Date) value;
                    d = new Date(qd.getTime());
                    o.put(key, d);
                }
                break;
            case TIMESTAMPTODATE:
                if (value == null){
                    o.put(key,null);
                } else {
                    java.sql.Timestamp qt = (Timestamp) value;
                    d = new Date(qt.getTime());
                    o.put(key, d);
                }
                break;
            case STRINGTOSTRING:
                if (value == null){
                    o.put(key,"");
                } else {
                    o.put(key, value);
                }
                break;
            case UNCHANGE:
                o.put(key, value);
                break;
            default:
                o.put(key, value);
                break;
        }
    }
    return o;
}

//Excel 工具类

public static Workbook openForWrite(String fileName) throws IOException {
    File file = new File(fileName);
    Workbook wb;
    InputStream is;
    try {
        is = new FileInputStream(file);
    } catch (FileNotFoundException e) {
        return null;
    }
    String ext = BaseUtil.getExtendName(fileName);
    if (".xls".equals(ext)) {
        wb = new HSSFWorkbook(is);
    } else if (".xlsx".equals(ext)) {
        wb = new XSSFWorkbook(is);
    } else {
        return null;
    }
    return wb;
}

//写入Row

public static void writeRow(Workbook wb,Row row,JSONObject value,String[] fields){
    DataFormat format = wb.createDataFormat();   //--->单元格内容格式
    //样式1
    CellStyle style = wb.createCellStyle(); // 样式对象
    style.setVerticalAlignment(HSSFCellStyle.VERTICAL_CENTER);// 垂直
    style.setAlignment(HSSFCellStyle.ALIGN_CENTER);// 水平
    style.setWrapText(true);   //设置是否能够换行，能够换行为true
    style.setBorderBottom((short) 1);   //设置下划线，参数是黑线的宽度
    style.setBorderLeft((short) 1);   //设置左边框
    style.setBorderRight((short) 1);   //设置有边框
    style.setBorderTop((short) 1);   //设置下边框
    style.setDataFormat(format.getFormat("￥#,##0"));    //--->设置为单元格内容为货币格式
    style.setDataFormat(format.getFormat("@"));
    Font font = wb.createFont();
    font.setFontHeightInPoints((short) 10);   //--->设置字体大小
    font.setFontName("Courier New");   //---》设置字体，是什么类型例如：宋体
    font.setItalic(true);     //--->设置是否是加粗
    style.setFont(font);     //--->将字体格式加入到style1中

    for(int i = 0;i < fields.length;i++){
        Cell cell = row.createCell(i);
        cell.setCellStyle(style);
        String key = fields[i];
        String v = value.getString(key);
        cell.setCellValue(v);
    }
}

//保存一个new File

public static void saveAsNewFile(String fileName,Workbook wb) throws IOException {
    OutputStream os = new FileOutputStream(fileName);
    wb.write(os);
    os.close();
}

//下载download

public static void download(HttpServletResponse response,File f,String contentType,String fileName){
    download(response, f, contentType, fileName, 8192);
}