java - Tomcat 7 和 ScheduledExecutorService.shutdown

Question

我正在使用 ScheduledExecutorService 来运行计划线程。
我实现了 ServletContextListener.contextDestroyed 并调用了 ScheduledExecutorService.shutdownNow 和 awaitTermination。

这是一个例子:

@Override
public void contextDestroyed(ServletContextEvent servletcontextevent) {
    pool.shutdownNow(); // Disable new tasks from being submitted
    try {
      // Wait a while for existing tasks to terminate
      if (!pool.awaitTermination(50, TimeUnit.SECONDS)) {
        pool.shutdownNow(); // Cancel currently executing tasks
        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();
    }        
}

不过，我从 Tomcat 7 收到以下错误:

SEVERE: The web application [/servlet] appears to have started a thread named [Timer-0] but has failed to stop it. This is very likely to create a memory leak.

这个日志可以忽略吗？还是我做错了什么？

谢谢

Answer 1

您确定此错误与您的线程池有关吗？根据线程名称“Timer-0”判断，它可能是由某种计时器启动的。

此外，shutdownNow() 应该返回仍在等待终止的任务列表(请参阅 JavaDoc)。如果列表不为空，您可以构建等待更多时间的逻辑。