java - 无法在 Spring Boot 中使用 @Async

Question

我想使用spring boot的异步机制，这是我的代码。

@Slf4j
@Configuration
@EnableAsync
public class AsyncConfig implements AsyncConfigurer {

    private static final int MAX_POOL_SIZE = 50;

    private static final int CORE_POOL_SIZE = 20;

    @Override
    public Executor getAsyncExecutor() {
        ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
        taskExecutor.setBeanName("taskExecutor");
        taskExecutor.setMaxPoolSize(MAX_POOL_SIZE);
        taskExecutor.setCorePoolSize(CORE_POOL_SIZE);
        taskExecutor.setThreadNamePrefix("async-task-thread-pool");
        taskExecutor.setWaitForTasksToCompleteOnShutdown(true);
        taskExecutor.setAwaitTerminationSeconds(60 * 10);
        taskExecutor.setRejectedExecutionHandler(
            (r, executor) -> log.warn("current thread pool is full, reject to invoke."));
        taskExecutor.initialize();
        return taskExecutor;
    }

    @Override
    public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
        return (ex, method, params) ->
        {
            log.error("invoke async method occurs error. method: {}, params: {}",
                method.getName(), JSON.toJSONString(params), ex);
            throw new RuntimeException();
        };
    }

}

我在另一个类的方法上添加了 @Async 注释。

@Override
public Future<Result> getResult(String name); 

但是当我调用 getResult() 方法时，它报告No bean named 'taskExecutor' available: Nomatching Executor bean find for qualifier 'taskExecutor' - 既没有限定符匹配，也没有bean名称匹配!。

然后我找到这个页面:https://www.baeldung.com/spring-async 。我遵循此页面的指南 - 删除 Application.class 上的 @EnableAsync 注释并添加到 AsyncConfig.class。但仍然收到相同的错误消息。似乎 setBeanName() 方法不起作用。难道是我的用法错误？

顺便说一句，我读过EnableAsync的api文档，它写道

Note: In the above example the {@code ThreadPoolTaskExecutor} is not a fully managed Spring bean. Add the {@code @Bean} annotation to the {@code getAsyncExecutor()} method

if you want a fully managed bean. In such circumstances it is no longer necessary to manually call the {@code executor.initialize()} method as this will be invoked automatically when the bean is initialized.

不是完全托管的 Spring bean 是什么意思？ bean 的哪一部分不由 Spring 管理？

Answer 1

向您的 Bean 注释添加名称，例如 @Bean(name="taskExecutor")。这应该使您的 bean 可以在名称 taskExecutor 下使用。默认情况下，它注册一个名为 methodName 的 bean。请参阅此处引用Spring Bean