SpringBoot 异步调用@Async

一、启动类注解 @EnableAsync

@EnableEurekaClient
@SpringBootApplication(scanBasePackages = {"com.csvw.cloud.**"})
@MapperScan({"com.csvw.cloud.dms.report.mapper","com.csvw.cloud.dms.framework.mapper"})
@EnableSwagger2
@EnableAsync
@EnableFeignClients(basePackages = {"com.csvw.cloud.**"})
@EnableApolloConfig({"application_common","application.yaml","application_basic.yaml"})
public class ReportServiceApplication {

    public static void main(String[] args) {
        SpringApplication.run(ReportServiceApplication.class, args);
    }
}

二、Controller层

    /**
     * 维修委托书查询（复杂）导出Excel并上传OBS - PC
     *
     * @param queryRepairOrderComplexPageDTO 查询传参
     * @param request request
     * @param response response
     * @author Tansj
     * @since 2020/06/04
     */
    @ApiOperation(notes="维修委托书查询（复杂）导出Excel并上传OBS - PC", value="维修委托书查询（复杂）导出Excel并上传OBS - PC")
    @ApiImplicitParams({
            @ApiImplicitParam(value = "47c163ad2ac34d94808ebbc0f424b566", name = "userId", required = true, dataType = "string", paramType = "header"),
            @ApiImplicitParam(value = "76612345", name = "dealerCode", required = true, dataType = "string", paramType = "header")})
    @GetMapping("/exportRepairOrderComplexUpload")
    public void exportRepairOrderComplexUploadMain(QueryRepairOrderComplexPageDTO queryRepairOrderComplexPageDTO, HttpServletRequest request,
                                           HttpServletResponse response) throws UnsupportedEncodingException, InterruptedException {
        long start = System.currentTimeMillis();
        repairReportService.exportRepairOrderComplexUpload(queryRepairOrderComplexPageDTO, request, response);
        long end = System.currentTimeMillis();
        log.info("维修委托书复杂导出异步调用Async:----------------, 耗时[{}]毫秒", end - start);
    }

三、ServiceImpl实现类 @Async

/**
 * <p>ClassName: RepairReportServiceImpl</p>
 * <p>Description: 维修报表ServiceImpl</p>
 * <p>Author: Tansj</p>
 * <p>Date: 2020年03月12日</p>
 */
@Slf4j
@Service
@EnableAsync
public class RepairReportServiceImpl implements RepairReportService {
    
    /**
     * 维修委托书查询（复杂）导出Excel并上传OBS - PC
     *
     * @param queryRepairOrderComplexPageDTO 查询传参
     * @param request request
     * @param response response
     * @author Tansj
     * @since 2020/06/04
     */
    @Override
    @Async
    public void exportRepairOrderComplexUpload(QueryRepairOrderComplexPageDTO queryRepairOrderComplexPageDTO,
                                               HttpServletRequest request, HttpServletResponse response) throws UnsupportedEncodingException, InterruptedException {
        ......
    }
 }

四、同步接口中的异步调用

    // ============Controller层============
    /**
     * 带有返回值的异步调用 - 测试使用
     *
     * @return String
     * @author Tansj
     * @since 2021/04/01
     */
    @ApiOperation(notes="带有返回值的异步调用 - 测试使用", value="带有返回值的异步调用 - 测试使用")
    @ApiImplicitParams({
            @ApiImplicitParam(value = "47c163ad2ac34d94808ebbc0f424b566", name = "userId", required = true, dataType = "string", paramType = "header"),
            @ApiImplicitParam(value = "76612345", name = "dealerCode", required = true, dataType = "string", paramType = "header")})
    @GetMapping("/getAsyncReturnFunction")
    public String getAsyncReturnFunction() {
        repairReportService.getAsyncReturnFunction();
        return "正在下载中，请稍后...";
    }

    // ============ServiceImpl层============
    /**
     * 带有返回值的异步调用 - 测试使用
     *
     * @return Future<String>
     * @author Tansj
     * @since 2021/04/01
     */
    @Override
    @Async
    public Future<String> getAsyncReturnFunction() {
        log.info("Execute method asynchronously -----------------{}", Thread.currentThread().getName());
        try {
            long start = System.currentTimeMillis();
            Thread.sleep(5000);
            long end = System.currentTimeMillis();
            log.info("带有返回值的异步调用Async:----------------, 耗时[{}]毫秒", end - start);
            return new AsyncResult<>("内部的返回结果");
        } catch (Exception e) {
            log.error(e.getMessage());
        }
        return null;
    }

直接返回前端结果为【正在下载中，请稍后...】，等待时间10ms。

    // ...接上文...
    // ============Controller层============
    /**
     * 同步接口中的异步调用 - 测试使用
     *
     * @return String
     * @author Tansj
     * @since 2021/04/01
     */
    @ApiOperation(notes="同步接口中的异步调用", value="同步接口中的异步调用")
    @ApiImplicitParams({
            @ApiImplicitParam(value = "47c163ad2ac34d94808ebbc0f424b566", name = "userId", required = true, dataType = "string", paramType = "header"),
            @ApiImplicitParam(value = "76612345", name = "dealerCode", required = true, dataType = "string", paramType = "header")})
    @GetMapping("/testAsyncReturnFunction")
    public String testAsyncReturnFunction() throws ExecutionException, InterruptedException {
        String result = "";
        Future<String> future = repairReportService.getAsyncReturnFunction();
        while (true) {  ///这里使用了循环判断，等待获取结果信息
            if (future.isDone()) {  //判断是否执行完毕
                System.out.println("Result from asynchronous process - " + future.get());
                result = future.get();
                break;
            }
            System.out.println("Continue doing something else. ");
            Thread.sleep(1000);
        }
        return result;
    }

等待返回前端结果为【内部的返回结果】，等待时间5000ms。