如果线程池中线程异常后：销毁还是复用？

hi，我是阿昌，今天分享一下如果线程池中线程异常后：销毁还是复用？

下面讨论的线程池是：java.util.concurrent.ExecutorService线程池

通过 execute提交任务

测试代码：

public static void main(String[] args) {
  ExecutorService executorService = buildThreadPoolExecutor();
  executorService.execute(() -> exeTask("achang-execute"));
  executorService.execute(() -> exeTask("achang-execute"));
  executorService.execute(() -> exeTask("achang-execute-exception"));
  executorService.execute(() -> exeTask("achang-execute"));
  executorService.execute(() -> exeTask("achang-execute"));


  try {
    Thread.sleep(5000);
  } catch (InterruptedException e) {
    throw new RuntimeException(e);
  }
  System.out.println("再次执行任务=======================");

  executorService.execute(() -> exeTask("achang-execute"));
  executorService.execute(() -> exeTask("achang-execute"));
  executorService.execute(() -> exeTask("achang-execute"));
  executorService.execute(() -> exeTask("achang-execute"));
  executorService.execute(() -> exeTask("achang-execute"));
}

public static ExecutorService buildThreadPoolExecutor() {
  return new ThreadPoolExecutor(5, 10, 30, TimeUnit.SECONDS,
                                new LinkedBlockingQueue<>(1000), new ThreadFactoryBuilder().setNameFormat("achang-test-%s").build()
                                , new ThreadPoolExecutor.CallerRunsPolicy());
}

private static void exeTask(String name) {
  String printStr = "[thread-name:" + Thread.currentThread().getName() + ",执行方式:" + name + "]";
  if ("achang-execute-exception".equals(name)) {
    throw new RuntimeException(printStr + ", 我出现了异常了");
  } else {
    System.out.println(printStr);
  }
}

执行结果：

结论：

execute 提交到线程池的方式，如果执行中抛出异常，并且没有在执行逻辑中catch，那么会抛出异常，并且移除抛出异常的线程，创建新的线程放入到线程池中。

通过submit提交任务

测试代码：

public static void main(String[] args) {
		ExecutorService executorService = buildThreadPoolExecutor();
		executorService.submit(() -> exeTask("achang-submit"));
		executorService.submit(() -> exeTask("achang-submit"));
		executorService.submit(() -> exeTask("achang-submit-exception"));
		executorService.submit(() -> exeTask("achang-submit"));
		executorService.submit(() -> exeTask("achang-submit"));
		
		
		try {
			Thread.sleep(5000);
		} catch (InterruptedException e) {
			throw new RuntimeException(e);
		}
		System.out.println("再次执行任务=======================");
		
		executorService.submit(() -> exeTask("achang-submit"));
		executorService.submit(() -> exeTask("achang-submit"));
		executorService.submit(() -> exeTask("achang-submit"));
		executorService.submit(() -> exeTask("achang-submit"));
		executorService.submit(() -> exeTask("achang-submit"));
	}
	
	public static ExecutorService buildThreadPoolExecutor() {
		return new ThreadPoolExecutor(5, 10, 30, TimeUnit.SECONDS,
				new LinkedBlockingQueue<>(1000), new ThreadFactoryBuilder().setNameFormat("achang-test-%s").build()
				, new ThreadPoolExecutor.CallerRunsPolicy());
	}
	
	private static void exeTask(String name) {
		String printStr = "[thread-name:" + Thread.currentThread().getName() + ",执行方式:" + name + "]";
		if ("achang-execute-exception".equals(name)) {
			throw new RuntimeException(printStr + ", 我出现了异常了");
		} else {
			System.out.println(printStr);
		}
	}