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Excel下载接口

需求分析

• 页面表格的数据下载，保存到Excel表格
• 搜索后的数据点击下载，下载的数据需要是搜索后的数据

• Controller

HTTP 响应对象:httpServletResponse

BalanceDownload.class:数据对象的类型

list:导出的数据列表

merchant_balance:merchant_balance

   @GetMapping("download")
   @ApiOperation("下载数据")
   public void balanceDownload(ReqMerchantBalanceQuery query) {
        List<BalanceDownload> list = merchantBalanceService.balanceDownload(query);
        try {
            ExcelTools.download(httpServletResponse, BalanceDownload.class, list, "merchant_balance");
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

• ReqMerchantBalanceQuery.java（请求体：前端搜索后传递过来的请求参数）

@Data
public class ReqMerchantBalanceQuery extends PageQuery {
    @ApiModelProperty("商户号")
    @IsMSearch(field = SettleTransactionDetailCol.MERCHANT_NO)
    private String merchantNo;
    @ApiModelProperty("币种")
    @IsMSearch(field = SettleTransactionDetailCol.SETTLE_CURRENCY)
    private String currency;
}

Excel工具类

public class ExcelTools {
    public ExcelTools() {
    }

    public static <T> List<T> excelToList(Class<T> clazz, InputStream is) {
        List<T> list = new ArrayList();
        EasyExcel.read(is, clazz, new PageReadListener((l) -> {
            list.addAll(l);
        })).sheet().doRead();
        return list;
    }

    public static <T> void download(HttpServletResponse response, Class<T> clazz, List<T> data, String type) throws IOException {
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        response.setCharacterEncoding("utf-8");
        response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + createFileName(type) + ".xlsx");
        HorizontalCellStyleStrategy horizontalCellStyleStrategy = new HorizontalCellStyleStrategy(ExcelStyleUtils.getHeadStyle(), ExcelStyleUtils.getContentStyle());
        ExcelCellWidthStyleStrategy widthStyleStrategy = new ExcelCellWidthStyleStrategy();
        ((ExcelWriterSheetBuilder)((ExcelWriterSheetBuilder)EasyExcel.write(response.getOutputStream(), clazz).sheet("模板").registerWriteHandler(horizontalCellStyleStrategy)).registerWriteHandler(widthStyleStrategy)).doWrite(data);
    }

    public static <T> void download(HttpServletResponse response, Class<T> clazz, List<T> data, String type, LinkedHashSet<String> includeColumnFiledNames) throws IOException {
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        response.setCharacterEncoding("utf-8");
        response.setHeader("Content-disposition", "attachment;filename*=utf-8''" + createFileName(type) + ".xlsx");
        HorizontalCellStyleStrategy horizontalCellStyleStrategy = new HorizontalCellStyleStrategy(ExcelStyleUtils.getHeadStyle(), ExcelStyleUtils.getContentStyle());
        ExcelCellWidthStyleStrategy widthStyleStrategy = new ExcelCellWidthStyleStrategy();
        ((ExcelWriterSheetBuilder)((ExcelWriterSheetBuilder)((ExcelWriterBuilder)EasyExcel.write(response.getOutputStream(), clazz).includeColumnFieldNames(includeColumnFiledNames)).sheet("模板").registerWriteHandler(horizontalCellStyleStrategy)).registerWriteHandler(widthStyleStrategy)).doWrite(data);
    }

    public static String createFileName(String type) {
        return type + "-" + LocalDateTime.now().format(DateTimeFormatter.ISO_LOCAL_DATE_TIME);
    }
}

• Service

query.setCurrency(query.getCurrency().toUpperCase()):将传递的币种进行大写转换

merchantSettleBalanceRepo.balanceListDownload(query): 方法获取了一个 List<MerchantSettleBalance> 类型的数据列表 list

list.stream().map(……).collect(Collectors.toList()):使用流式操作对 list 进行转换，将每个 MerchantSettleBalance 对象映射为一个 BalanceDownload 对象；使用 Collectors.toList() 方法将转换后的结果收集为一个 List<BalanceDownload> 对象，并将其返回

    public List<BalanceDownload> balanceDownload(ReqMerchantBalanceQuery query) {
        if (query.getCurrency() != null) {
            query.setCurrency(query.getCurrency().toUpperCase());
        }
        List<MerchantSettleBalance> list = merchantSettleBalanceRepo.balanceListDownload(query);
        List<BalanceDownload> collect = list.stream().map(bean -> new BalanceDownload(
                bean.getMerchantNo(),
                bean.getSettleCurrency(),
                Amount.getInstance(bean.getSettleCurrency(), bean.getTotalSettleAmount()).getShowAmount(),
                Amount.getInstance(bean.getSettleCurrency(), bean.getUnWithdrawAmount()).getShowAmount(),
                Amount.getInstance(bean.getSettleCurrency(), bean.getWithdrawedAmount()).getShowAmount(),
                Amount.getInstance(bean.getSettleCurrency(), bean.getAuditWithdrawAmount()).getShowAmount(),
                Amount.getInstance(bean.getSettleCurrency(), bean.getToBeSettledAmount()).getShowAmount(),
                Amount.getInstance(bean.getSettleCurrency(), bean.getCashDepositAmount()).getShowAmount()
        )).collect(Collectors.toList());
        return collect;
    }

• Repo

List<MerchantSettleBalance> balanceListDownload(ReqMerchantBalanceQuery query);

• Impl

baseMapper.selectList(MSearchTools.createQueryWrapper(MerchantSettleBalance.class, query)):使用给定的查询条件query查询数据库中的MerchantSettleBalance实体，并返回查询结果列表

    @Override
    public List<MerchantSettleBalance> balanceListDownload(ReqMerchantBalanceQuery query) {
        return baseMapper.selectList(MSearchTools.createQueryWrapper(MerchantSettleBalance.class, query));
    }

• BalanceDownload.java（下载Excel中展示字段）

@Data
@AllArgsConstructor
@NoArgsConstructor
@Builder
public class BalanceDownload {

    @ExcelProperty("Merchant No")
    private String merchantNo;
    @ApiModelProperty("Currency")
    private String currency;
    @ApiModelProperty("TotalSettle Amount")
    private String totalSettleAmount;
    @ApiModelProperty("CanWithdraw Amount")
    private String canWithdrawAmount;
    @ApiModelProperty("Withdrawed Amount")
    private String withdrawedAmount;
    @ApiModelProperty("AuditWithDraw Amount")
    private String auditWithdrawAmount;
    @ApiModelProperty("ToBeSettle Amount")
    private String toBeSettleAmount;
    @ApiModelProperty("CashDeposit Amount")
    private String cashDepositAmount;
}

测试

• Postman接口调试

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