异步线程池配置：

/*** 启动异步线程-并配置线程池*/
@Configuration
@EnableAsync
public class AsyncConfig {@Bean(name = "taskExecutor")public Executor taskExecutor() {ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();executor.setCorePoolSize(2); // 核心线程数executor.setMaxPoolSize(5); // 最大线程数executor.setQueueCapacity(500); // 队列容量executor.setThreadNamePrefix("Async-"); // 线程名称前缀executor.initialize();return executor;}
}

异步线程服务

/*** 异步线程服务** @author Lance* @since 2024-07-11 10:07*/
@Component
public class AsyncTaskService {private static final Logger logger = LoggerFactory.getLogger(AsyncTaskService.class);// 默认最大重试次数private static final int DEFAULT_MAX_ATTEMPTS = 3;// 默认重试间隔时间private static final long DEFAULT_DELAY_BETWEEN_ATTEMPTS = 1000;/*** 启动一个异步任务，并使用重试机制** @param task 待执行的任务* @param <T>  类型* @return 返回结果*/@Asyncpublic <T> CompletableFuture<T> executeAsyncTaskWithRetry(Callable<T> task) {return executeAsyncTaskWithRetry(task, DEFAULT_MAX_ATTEMPTS, DEFAULT_DELAY_BETWEEN_ATTEMPTS);}/*** 启动一个异步任务，并使用重试机制** @param task         待执行的任务* @param maxAttempts  最大重试次数* @param initialDelay 重试间隔时间* @param <T>          类型* @return 返回结果*/@Asyncpublic <T> CompletableFuture<T> executeAsyncTaskWithRetry(Callable<T> task, int maxAttempts, long initialDelay) {CompletableFuture<T> future = new CompletableFuture<>();ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1);executeTaskWithRetry(task, maxAttempts, initialDelay, future, scheduler, 0, new ArrayList<>());return future;}private <T> void executeTaskWithRetry(Callable<T> task, int maxAttempts, long initialDelay, CompletableFuture<T> future, ScheduledExecutorService scheduler, int attempt, List<Exception> exceptions) {if (attempt >= maxAttempts) {RuntimeException exception = new RuntimeException("任务失败，已达最大重试次数: " + maxAttempts);exceptions.forEach(exception::addSuppressed);future.completeExceptionally(exception);scheduler.shutdown();logger.error("任务失败，已达最大重试次数: {}", maxAttempts, exception); // 添加这行来打印错误信息return;}CompletableFuture<T> attemptFuture = CompletableFuture.supplyAsync(() -> {try {return task.call();} catch (Exception e) {throw new CompletionException(e);}});attemptFuture.whenComplete((result, throwable) -> {if (throwable == null) {future.complete(result);scheduler.shutdown();} else {// 指数退避策略来计算重试间隔 延迟时间是初始延迟initialDelay乘以2的attempt次方long delay = (long) (initialDelay * Math.pow(2, attempt));logger.info("任务失败，将在 {} 毫秒后重试，尝试第：{} 次", delay, attempt + 1);exceptions.add((Exception) throwable.getCause());scheduler.schedule(() -> executeTaskWithRetry(task, maxAttempts, initialDelay, future, scheduler, attempt + 1, exceptions), delay, TimeUnit.MILLISECONDS);}});}/*** 启动一个无返回的异步任务** @param task 待执行的任务*/@Asyncpublic void executeAsyncRunnableTask(Runnable task) {task.run();}
}

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执行测试：

@RestController
public class AsyncController {@Resourceprivate AsyncTaskService genericAsyncService;@GetMapping("/startAsyncTask")@ApiOperation("执行异步任务")public String startAsyncTask() {genericAsyncService.executeAsyncTaskWithRetry(() -> {System.out.println("执行异步任务: " + Thread.currentThread().getName());Thread.sleep(5000); // 模拟长时间运行的任务System.out.println("异步任务完成: " + Thread.currentThread().getName());return "任务结果";});return "异步任务已启动";}@GetMapping("/startAsyncRunnableTask")@ApiOperation("不需要返回值的操作的任务")public String startAsyncRunnableTask() {genericAsyncService.executeAsyncRunnableTask(() -> {System.out.println("执行异步Runnable任务: " + Thread.currentThread().getName());// 执行一些不需要返回值的操作// 例如，发送电子邮件、更新数据库、日志记录等System.out.println("异步Runnable任务完成: " + Thread.currentThread().getName());});return "异步Runnable任务已启动";}private static final Random RANDOM = new Random();@GetMapping("/executeTask")@ApiOperation("执行异步任务[重试]")public ResponseEntity<CompletableFuture<String>> executeTask() {// 创建一个Callable任务Callable<String> myTask = () -> {// 随机生成一个0到9之间的数字int randomNumber = RANDOM.nextInt(10);System.out.println("我是任务 ====== 随机数" + randomNumber);// 如果随机数小于5，则抛出异常，模拟任务失败if (randomNumber < 5) {System.out.println("随机数: " + randomNumber + "，任务将失败。");throw new Exception("随机失败");}return "Task executed successfully";};// 调用executeAsyncTaskWithRetry方法CompletableFuture<String> resultFuture = genericAsyncService.executeAsyncTaskWithRetry(myTask);// 返回CompletableFuture作为响应return new ResponseEntity<>(resultFuture, HttpStatus.OK);}}

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