SpringBoot中大量数据导出方案：使用EasyExcel并行导出多个excel文件并压缩zip后下载

@RestController
public class SalesOrderController {
    @Resource
    private SalesOrderExportService salesOrderExportService;
   @PostMapping(value = "/salesOrder/export")
    public void salesOrderExport(@RequestBody @Validated RequestDto req, HttpServletResponse response) {
        salesOrderExportService.salesOrderExport(req, response);
    }
 
}

@Slf4j
@Service
public class SalesOrderExportService {
 
    @Autowired
    @Qualifier("threadPoolTask")
    private ThreadPoolTaskExecutor threadPoolTaskExecutor;
 
    @Resource
    private OrderManager OrderManager;
 
 
 public void salesOrderExport(RequestDto req, HttpServletResponse response) {
  
   // 获取导出数据,每个SalesOrder实例需要分别导出到一个excel文件
   List<SalesOrder> orderDataList = OrderManager.getOrder(req.getUserCode());
   // 略...校验数据
   
   InputStream zipFileInputStream = null;
   Path tempZipFilePath = null;
   Path tempDir = null;
   // 获取导出模板
   try (InputStream templateInputStream = this.getClass().getClassLoader().getResourceAsStream("template/order_template.xlsx");
     ByteArrayOutputStream outputStream = new ByteArrayOutputStream();) {
     
    if (Objects.isNull(templateInputStream)) {
     throw new RuntimeException("获取模版文件异常");
    }
    // 多线程服用一个文件流
    IOUtils.copy(templateInputStream, outputStream);
    
    // 创建临时excel文件导出目录,用于将多个excel导出到此目录下
    Path tmpDirRef = (tempDir = Files.createTempDirectory(req.userCode() + "dir_prefix"));
     
    // 每5个salesOrder一个线程并行导出到excel文件中
    CompletableFuture[] salesOrderCf = Lists.partition(orderDataList, 5).stream()
    .map(orderDataSubList -> CompletableFuture
      .supplyAsync(() -> orderDataSubList.stream()
        .map(orderData -> this.exportExcelToFile(tmpDirRef, outputStream, orderData))
        .collect(Collectors.toList()), threadPoolTaskExecutor)
      .exceptionally(e -> {throw new RuntimeException(e);}))
    .toArray(CompletableFuture[]::new);
   
    // 等待所有excel文件导出完成
    CompletableFuture.allOf(salesOrderCf).get(3, TimeUnit.MINUTES);
    
    // 创建临时zip文件
    tempZipFilePath = Files.createTempFile(req.userCode() + TMP_ZIP_DIR_PRE, ".zip");
    
    // 将excel目录下的所有文件压缩到zip文件中,zipUtil有很多工具包都有
    ZipUtil.zip(tempDir.toString(), tempZipFilePath.toString());
    
    response.setContentType("application/octet-stream;charset=UTF-8");
    response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(tempZipFilePath.toFile().getName(), "utf-8"));
    
    // 写zip文件流到response
    zipFileInputStream = Files.newInputStream(tempZipFilePath);
    IOUtils.copy(zipFileInputStream, response.getOutputStream());
   } catch (Exception e) {
    log.error("salesOrderExport,异常:", e);
    throw new RuntimeException("导出异常,请稍后重拾");
   } finally {
      try {  
         // 关闭流
        if (Objects.nonNull(zipFileInputStream)) {
           zipFileInputStream.close();
         }    
        // 删除临时文件及目录
        if (Objects.nonNull(tempDir)) {
           Files.walkFileTree(tempDir, new SimpleFileVisitor<Path>() {
              @Override
              public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
                   Files.deleteIfExists(file);
                   return FileVisitResult.CONTINUE;
              }
             @Override
             public FileVisitResult postVisitDirectory(Path dir, IOException exc) throws IOException {
                 Files.deleteIfExists(dir);
                 return FileVisitResult.CONTINUE;
              }
            });
        }
        if (Objects.nonNull(tempZipFilePath)) {
          Files.deleteIfExists(tempZipFilePath);
        }
    } catch (Exception e) {
        log.error("salesOrderExport, 关闭文件流失败:", e);
    }
   }

/**
   * 导出单个excle文件,上面的多线程代码调用
   **/
 private Path exportExcelToFile(Path temporaryDir, ByteArrayOutputStream templateOutputStream, SalesOrder data) {
     Path temproaryFilePath = null;
     try {
         // 创建临时文件 
         temproaryFilePath = Files.createTempFile(temporaryDir, data.getOrderNo(), ExcelTypeEnum.XLSX.getValue());
     } catch (IOException e) {
         throw new RuntimeException("exportExcelToFile,创建excel临时文件失败:" + data.getOrderNo());
     }
     try (InputStream templateInputStream = new ByteArrayInputStream(templateOutputStream.toByteArray());
          OutputStream temporaryFileOs = Files.newOutputStream(temproaryFilePath);
          BufferedOutputStream tempOutStream = new BufferedOutputStream(temporaryFileOs)) {
    
        // 使用easyExcel的模板功能导出订单数据到临时文件中 
         ExcelWriter excelWriter = EasyExcel.write(tempOutStream, SalesOrder.class)
                 .withTemplate(templateInputStream).excelType(ExcelTypeEnum.XLSX).build();
   
         // 填充模板数据
         WriteSheet writeSheet = EasyExcel.writerSheet().build();
         FillConfig fillConfig = FillConfig.builder().forceNewRow(Boolean.TRUE).build();
         excelWriter.fill(new FillWrapper("goods", data.getGoodsList()), fillConfig, writeSheet);
         excelWriter.fill(data, writeSheet);
         excelWriter.finish();
         // temproaryFilePath.toFile().deleteOnExit();
         return temproaryFilePath;
     } catch (Exception e) {
         throw new RuntimeException("exportExcelToFile,导出excel文件失败:" + data.getOrderNo(), e);
     }
 }