线程池-shutdown和awaitTermination

电玩女神 2022-07-16 10:52 184阅读 0赞

## 1.shutdown和awaitTermination ##

shutdown:启动线程池的有序关闭过程，其等待已经提交的所有任务完成之后关闭线程池。当调用该方法后，线程池不再接受其他任务。并且该方法是非阻塞的，不会等待所有任务执行成功后返回。

**调用线程直接返回**

public class SleepWorker implements Runnable { 
        private static final Logger LOGGER = LoggerFactory.getLogger(SleepWorker.class);
    
        @Override
        public void run() {
            String threadName = Thread.currentThread().getName();
            try {
                LOGGER.info("threadName={} 开始线程worker工作", threadName);
                Thread.sleep(2000);
                LOGGER.info("threadName={} 结束线程worker工作", threadName);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
    
    public class ShutDownNoWait { 
        private static final Logger LOGGER = LoggerFactory.getLogger(ShutDownNoWait.class);
    
        public static void main(String[] args) {
            int workerNum = 5;
            ExecutorService executorService = Executors.newFixedThreadPool(workerNum);
            for (int i = 0; i < workerNum; i++) {
                executorService.submit(new SleepWorker());
            }
            executorService.shutdown();
            LOGGER.info("调用shutdown会立即返回不会等待线程池任务执行完");
        }
    }

10:46:21.944  INFO (ShutDownNoWait.java:23) - 调用shutdown会立即返回不会等待线程池任务执行完
    10:46:23.949  INFO (SleepWorker.java:18) - threadName=pool-1-thread-1 结束线程worker工作
    10:46:23.949  INFO (SleepWorker.java:18) - threadName=pool-1-thread-2 结束线程worker工作

**调用线程等待任务完成**

public class ShutDownWait { 
        private static final Logger LOGGER = LoggerFactory.getLogger(ShutDownWait.class);
    
        public static void main(String[] args) throws InterruptedException {
            int workerNum = 2;
            ExecutorService executorService = Executors.newFixedThreadPool(workerNum);
            for (int i = 0; i < workerNum; i++) {
                executorService.submit(new SleepWorker());
            }
            executorService.shutdown();
            executorService.awaitTermination(10, TimeUnit.SECONDS);
            LOGGER.info("调用shutdown会立即返回不会等待线程池任务执行完");
        }
    }

10:51:34.889  INFO (SleepWorker.java:18) - threadName=pool-1-thread-2 结束线程worker工作
    10:51:34.889  INFO (SleepWorker.java:18) - threadName=pool-1-thread-1 结束线程worker工作
    10:51:34.893  INFO (ShutDownWait.java:25) - 调用shutdown会立即返回不会等待线程池任务执行完