blocks|key|564088|text|如果jvm关闭，将调用shutdown钩子。确保程序退出。如果jedis在后台运行(在线程中)，即使执行了最后一条语句，shutdown钩子也不会调用。在这种情况下，您必须停止该线程。最好的方法是尝试使用jedis.shutdown();+(在添加shutdown钩子之后，这里是最后一条语句)来关闭它。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|564089|entityMap^0|2U|H|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

The shutdown hook will invoke if the jvm shuts down. Make sure that the program exits. If the jedis is running in the background (in a thread) even if the last statement is executed then the shutdown hook will not invoke. In such case, you have to stop that thread. The best way will be to try <code>jedis.shutdown();</code> (after adding shutdown hook, here as the last statement) to shut it down.

blocks|key|619016|text|“请注意，订阅是一个阻塞操作...”(来自the+AdvancedUsage+wiki)。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|619017|这反过来意味着只有在取消订阅或关闭Jedis之后才会注册shutdown-hook，并且您可能只在JVM已经关闭时才会访问该部分代码(在这种情况下，新添加的shutdown钩子会被忽略:必须在JVM关闭之前注册shutdown钩子)。|619018|“有关更多用法示例，请查看测试。”(来自main+Github+page)|619019|那么让我们来看看PublishSubscribeCommandsTest。|619020|测试只是一个订阅操作，但在订阅操作中，当JedisPubSub接收到特定消息时，它会取消订阅，从而解除自身的阻塞，以便测试可以完成。|style|CODE|619021|你可以尝试两件事：|619022|在调用jedis.subscribe|619023|copy测试中的代码之前，|unordered-list-item|619024|注册关闭钩子，并对其进行修改，以便您可以尝试阻塞和解除阻塞线程，并从关闭钩子中关闭|619025|(以清理使用的资源)|619026|619027|entityMap|0|LINK|mutability|MUTABLE|url|https://github.com/xetorthio/jedis/wiki/AdvancedUsage|1|https://github.com/xetorthio/jedis|2|https://github.com/xetorthio/jedis/blob/master/src/test/java/redis/clients/jedis/tests/commands/PublishSubscribeCommandsTest.java#L33^0|L|M|0|0|0|K|G|1|0|8|S|2|0|K|B|0|0|3|F|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|1B|8|@]|9|@$A|1C|B|1D|1|1E]]|C|$]]|$1|D|3|E|5|6|7|1F|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|1G|8|@]|9|@$A|1H|B|1I|1|1J]]|C|$]]|$1|H|3|I|5|6|7|1K|8|@]|9|@$A|1L|B|1M|1|1N]]|C|$]]|$1|J|3|K|5|6|7|1O|8|@$A|1P|B|1Q|L|M]]|9|@]|C|$]]|$1|N|3|O|5|6|7|1R|8|@]|9|@]|C|$]]|$1|P|3|Q|5|6|7|1S|8|@$A|1T|B|1U|L|M]]|9|@]|C|$]]|$1|R|3|S|5|T|7|1V|8|@]|9|@]|C|$]]|$1|U|3|V|5|T|7|1W|8|@]|9|@]|C|$]]|$1|W|3|X|5|6|7|1X|8|@]|9|@]|C|$]]|$1|Y|3|-4|5|6|7|1Y|8|@]|9|@]|C|$]]|$1|Z|3|-4|5|6|7|1Z|8|@]|9|@]|C|$]]]|10|$11|$5|12|13|14|C|$15|16]]|17|$5|12|13|14|C|$15|18]]|19|$5|12|13|14|C|$15|1A]]]]

"Note that subscribe is a blocking operation ..." (from <a href="https://github.com/xetorthio/jedis/wiki/AdvancedUsage" rel="nofollow">the AdvancedUsage wiki</a>).

This in turn means that the shutdown-hook is only registered after you unsubscribe or shutdown Jedis,
and you probably only reach that part of the code when the JVM is already shutting down 
(in which case the newly added shutdown hook is ignored: shutdown hooks have to be registered before the JVM shuts down).

"For more usage examples check the tests." (from the <a href="https://github.com/xetorthio/jedis" rel="nofollow">main Github page</a>)

So let's look at the <a href="https://github.com/xetorthio/jedis/blob/master/src/test/java/redis/clients/jedis/tests/commands/PublishSubscribeCommandsTest.java#L33" rel="nofollow">PublishSubscribeCommandsTest</a>.
 The test is just one subscribe operation but within the subscribe operation, the <code>JedisPubSub</code> un-subscribes itself when it receives a specific message thereby unblocking itself so that the test can finish.

Two things you can experiment with:

<ul>
<li>register the shutdown hook before calling <code>jedis.subscribe</code></li>
<li>copy the code from the test and modify it so you can experiment with blocking and unblocking threads and shutting down Jedis from within a shutdown hook (to clean up used resources)</li>
</ul>

blocks|key|619039|text|Main方法的常规退出与显式调用System.exit(0);略有不同|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|619040|因此，尝试如下所示：|619041|public+static+void+main(String[]+args)+throws+IOException+{
++++//all+your+code...
++++System.exit(0);+//NOTE:+non+zero+status+will+work+different!
}|code-block|syntax|javascript|619042|entityMap^0|G|F|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|R|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|S|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|T|8|@]|D|@]|E|$]]]|N|$]]

Regular exit of Main-Method differs a little from explicit calling <code>System.exit(0);</code> 

so, try following:

<pre><code>public static void main(String[] args) throws IOException {
 //all your code...
 System.exit(0); //NOTE: non zero status will work different!
}
</code></pre>

I have the following in my main method:

<pre><code>public static void main(String[] args) throws IOException {
 Properties properties = getConfig();
 Jedis jedis = configure(properties)

 jedis.subscribe(queueHandler, "queue");

 Runtime.getRuntime().addShutdownHook(new Thread() {
 @Override
 public void run() {
 logger.debug("SHUTTING DOWN");
 jedis.close();
 }
 });
}
</code></pre>

I noticed that the code inside my shutdown hook is never run, why is that? How do I clean up resources that my main method has a hold of?

Why isn't my shutdownhook in my main method being called?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我的main方法中包含以下内容：public static void main(String[] args) throws IOException {    Properties properties = getConfig();    Jedis jedis = configure(properties)    je...

问为什么我的main方法中的shutdownhook没有被调用？
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问为什么我的main方法中的shutdownhook没有被调用？EN