springboot线程池优雅关闭

在我们停止springboot项目时，我们希望线程池中的任务能够继续执行完再完全停掉服务。一般有两种做法：

线程池配置参数

在spring应用中，如果需要
停止服务，而线程池没有优雅的关闭，就会造成线程池中的任务被强行停止，导致部分任务执行失败。我们只需要在配置线程池时增加两个参数即可：

• waitForTasksToCompleteOnShutdown
• awaitTerminationSeconds 具体代码如下：

@Bean
public ThreadPoolTaskExecutor treadPool() {
    ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
    executor.setCorePoolSize(10);
    executor.setMaxPoolSize(20);
    executor.setQueueCapacity(10);
    executor.setKeepAliveSeconds(60);
    executor.setWaitForTasksToCompleteOnShutdown(true);
    executor.setAwaitTerminationSeconds(30);
    executor.setRejectedExecutionHandler(new ThreadPoolExecutor.CallerRunsPolicy());
    executor.initialize();
    return executor;
}

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使用ApplicationListener监听关闭事件

@Component
public class MyContextClosedHandler implements ApplicationListener<ContextClosedEvent>{
    @Autowired
    private ThreadPoolTaskExecutor executor;

    @Override
    public void onApplicationEvent(ContextClosedEvent event) {
        shutdownAndAwaitTermination(executor.getThreadPoolExecutor());
    }

    private void shutdownAndAwaitTermination(ExecutorService pool) {
        pool.shutdown(); // Disable new tasks from being submitted
        try {
            // Wait a while for existing tasks to terminate
            if (!pool.awaitTermination(30, TimeUnit.SECONDS)) {
                pool.shutdownNow(); // Cancel currently executing tasks
                // Wait a while for tasks to respond to being cancelled
                if (!pool.awaitTermination(30, TimeUnit.SECONDS))
                    System.err.println("Pool did not terminate");
            }
        } catch (InterruptedException ie) {
            // (Re-)Cancel if current thread also interrupted
            pool.shutdownNow();
            // Preserve interrupt status
            Thread.currentThread().interrupt();
        }
    }
}

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