Spring的异步线程处理

Spring封装了JDK的线程池和线程调用，并使用标签就可以开启多线程调用。

先进行一个Spring的线程池配置

@Configuration
@EnableAsync
public class ThreadPoolConfig implements AsyncConfigurer {
    @Bean
    @Override
    public Executor getAsyncExecutor() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setCorePoolSize(Runtime.getRuntime().availableProcessors());
        executor.setMaxPoolSize(Runtime.getRuntime().availableProcessors() * 5);
        executor.setQueueCapacity(Runtime.getRuntime().availableProcessors() * 2);
        executor.setThreadNamePrefix("this-executor-");
        executor.initialize();
        return executor;
    }

    @Bean
    @Override
    public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {
        return new SimpleAsyncUncaughtExceptionHandler();
    }
}

再编写一个Service的异步方法调用，这里是带返回值的，不带返回值的方法比较简单，这里就不举例了。

@Service
@Slf4j
public class ThreadTasks {
    /**
     * 如果异步方法有返回值，一定要使用Future包装，否则无法返回
     * @return
     * @throws InterruptedException
     */
    @Async
    public Future<String> startTask() throws InterruptedException {
        Thread.sleep(3000);
        log.info("this is async task");
        return new AsyncResult<>("123456");
    }
}

最后写一个Controller,对该异步方法进行调用

@RestController
public class AsyncTaskController {
    @Autowired
    private ThreadTasks tasks;

    @GetMapping("/users-anon/useTask")
    public String useSyncTask() throws InterruptedException, ExecutionException {
        Future<String> future = tasks.startTask();
        return future.get();
    }
}

最后运行下来，我们可以看到每次都是不同的线程执行

2020-09-21 16:33:53.027  INFO [user-center,3e635fca3d1259da,d30e8b6372922137,false] 1126 --- [this-executor-1] com.cloud.user.service.ThreadTasks       : this is async task
2020-09-21 16:35:27.664  INFO [user-center,9b68efbb2c848d7b,895ed921f6c8fe03,false] 1126 --- [this-executor-2] com.cloud.user.service.ThreadTasks       : this is async task