如何退出Java SDK中的SQS读取

我们有一个JavaWeb服务，它轮询AWS SQS队列中的消息。它使用20秒的最大等待时间。在Tomcat中更新服务时，Tomcat会尝试关闭现有服务，然后启动更新版本。发生这种情况时，如果正在读取队列，则线程被卡住，Tomcat无法停止它，从而导致内存泄漏。从我的实验来看，只有Tomcat在等待队列时试图停止服务时，才会发生内存泄漏

如何在关闭过程中停止Java中的SQS队列

这里有更多的细节

Jan 03, 2014 7:52:52 PM org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
SEVERE: The web application appears to have started a thread named [pollSQSQueue-1] but has failed to stop it. This is very likely to create a memory leak.
Jan 03, 2014 7:52:52 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application created a ThreadLocal with key of type [com.amazonaws.auth.AWS4Signer$2] (value [com.amazonaws.auth.AWS4Signer$2@71f69c90]) and a value of type [java.text.SimpleDateFormat] (value [java.text.SimpleDateFormat@ef87e460]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.
Jan 03, 2014 7:52:52 PM org.apache.catalina.loader.WebappClassLoader checkThreadLocalMapForLeaks
SEVERE: The web application created a ThreadLocal with key of type [com.amazonaws.auth.AWS4Signer$1] (value [com.amazonaws.auth.AWS4Signer$1@75a0ec63]) and a value of type [java.text.SimpleDateFormat] (value [java.text.SimpleDateFormat@6f64295a]) but failed to remove it when the web application was stopped. Threads are going to be renewed over time to try and avoid a probable memory leak.

该服务使用Spring并使用Spring调度程序来启动轮询过程

<task:scheduler id="pollSQSQueue" pool-size="1"/>

接下来我尝试使用AmazonSQSAsync和异步检索。然后，我获得了

未来

，并在Spring关机期间尝试调用

取消

。这也不是很得体

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另外，我知道需要关闭IdleConnectionReaper，并在Spring关闭时执行此操作，因此我认为这与此无关。

您可以为轮询工作创建单独的线程。大致如下：

class MyService extends/implements ... {
    private SQSPollingThread pollingThread;

    //this is just my guess of what the "service start" method looks like
    @Override
    public void onApplicationEvent(ContextStartedEvent contextStartedEvent)
    {
         pollingThread = new SQSPollingThread();
         pollingThread.start();
    }

    @Override
    public void onApplicationEvent(ContextClosedEvent contextClosedEvent)
    {
        pollingThread.stop();
    }
}

class SQSPollingThread implements Runnable() {
    private volatile boolean stopped = false;

    public void stop() {
        stopped = true;
    }

    @Override
    public void run() {
        while (!stopped) {
            message = pollSqsBlockingFor20seconds();
            process(message);
        }
    }
}

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通过这种设置，当TomCat“告诉”您的服务停止时，您的服务将设置停止标志并立即返回。可能仍有一个轮询请求挂起，最终将在接下来的20秒内完成并得到处理。处理完最后一个事件后，内部SQSPollingThread也将结束。

我遇到了同样的问题。你找到解决方案了吗？没有，我没有找到解决方案。你用什么来阅读SQS？我是说，线程是你的一个类？您可以发布代码吗？更好的是，您应该能够

中断执行轮询的线程，这样您就不必等待20秒的轮询。只要确保你不接受/忽略打断。
class MyService extends/implements ... {
    private SQSPollingThread pollingThread;

    //this is just my guess of what the "service start" method looks like
    @Override
    public void onApplicationEvent(ContextStartedEvent contextStartedEvent)
    {
         pollingThread = new SQSPollingThread();
         pollingThread.start();
    }

    @Override
    public void onApplicationEvent(ContextClosedEvent contextClosedEvent)
    {
        pollingThread.stop();
    }
}

class SQSPollingThread implements Runnable() {
    private volatile boolean stopped = false;

    public void stop() {
        stopped = true;
    }

    @Override
    public void run() {
        while (!stopped) {
            message = pollSqsBlockingFor20seconds();
            process(message);
        }
    }
}