blocks|key|417166|text|是。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|417167|您只需要创建自己的ThreadFactory类来创建守护进程线程，而不是常规线程。|offset|length|style|CODE|417168|entityMap^0|0|9|D|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@$D|L|E|M|F|G]]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

Yes.

You simply need to create your own <code>ThreadFactory</code> class that creates daemon threads rather than regular threads.

blocks|key|417256|text|可能最简单和首选的解决方案是在Marco13's+answer中，所以不要被投票差异(这个答案早了几年)或接受分数(它只是意味着这个解决方案适合于OP环境，而不是说它在一般情况下是最好的)所欺骗。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|417257|417258|您可以使用ThreadFactory将Executor中的线程设置为守护进程。这将在某种程度上影响executor服务，它也将成为守护线程，因此如果没有其他非守护线程，它(以及由它处理的线程)将停止。下面是一个简单的例子：|style|CODE|417259|ExecutorService+exec+=+Executors.newFixedThreadPool(4,
++++++++new+ThreadFactory()+{
++++++++++++public+Thread+newThread(Runnable+r)+{
++++++++++++++++Thread+t+=+Executors.defaultThreadFactory().newThread(r);
++++++++++++++++t.setDaemon(true);
++++++++++++++++return+t;
++++++++++++}
++++++++});

exec.execute(YourTaskNowWillBeDaemon);|code-block|syntax|javascript|417260|417261|但是如果你想让executor让它的任务完成，同时在应用程序完成时自动调用它的shutdown()方法，你可能想用Guava's+MoreExecutors.getExitingExecutorService包装你的executor。|417262|ExecutorService+exec+=+MoreExecutors.getExitingExecutorService(
++++++++(ThreadPoolExecutor)+Executors.newFixedThreadPool(4),+
++++++++100_000,+TimeUnit.DAYS//period+after+which+executor+will+be+automatically+closed
+++++++++++++++++++++++++++++//I+assume+that+100_000+days+is+enough+to+simulate+infinity
);
//exec.execute(YourTask);
exec.execute(()+->+{
++++for+(int+i+=+0;+i+<+3;+i%2B%2B)+{
++++++++System.out.println("daemon");
++++++++try+{
++++++++++++TimeUnit.SECONDS.sleep(1);
++++++++}+catch+(Exception+e)+{
++++++++++++e.printStackTrace();
++++++++}
++++}
});|417263|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/29453160/1393766|1|https://github.com/google/guava|2|https://google.github.io/guava/releases/snapshot-jre/api/docs/com/google/common/util/concurrent/MoreExecutors.html#getExitingExecutorService-java.util.concurrent.ThreadPoolExecutor-long-java.util.concurrent.TimeUnit-^0|F|G|0|0|0|5|D|0|0|0|13|A|1T|13|1L|7|1|1T|13|2|0|0^^$0|@$1|2|3|4|5|6|7|14|8|@]|9|@$A|15|B|16|1|17]]|C|$]]|$1|D|3|-4|5|6|7|18|8|@]|9|@]|C|$]]|$1|E|3|F|5|6|7|19|8|@$A|1A|B|1B|G|H]]|9|@]|C|$]]|$1|I|3|J|5|K|7|1C|8|@]|9|@]|C|$L|M]]|$1|N|3|-4|5|6|7|1D|8|@]|9|@]|C|$]]|$1|O|3|P|5|6|7|1E|8|@$A|1F|B|1G|G|H]|$A|1H|B|1I|G|H]]|9|@$A|1J|B|1K|1|1L]|$A|1M|B|1N|1|1O]]|C|$]]|$1|Q|3|R|5|K|7|1P|8|@]|9|@]|C|$L|M]]|$1|S|3|-4|5|6|7|1Q|8|@]|9|@]|C|$]]]|T|$U|$5|V|W|X|C|$Y|Z]]|10|$5|V|W|X|C|$Y|11]]|12|$5|V|W|X|C|$Y|13]]]]

Probably simplest and preferred solution is in <a href="https://stackoverflow.com/a/29453160/1393766">Marco13's answer</a> so don't get fooled by vote difference (this answer is few years older) or acceptance mark (it just means that this solution was appropriate for OP circumstances, not that it is best in general).
<hr />
You can use <code>ThreadFactory</code> to set threads inside Executor to daemons. This will affect executor service in a way that it will also become daemon thread so it (and threads handled by it) will stop if there will be no other non-daemon thread. Here is simple example:
<pre><code>ExecutorService exec = Executors.newFixedThreadPool(4,
 new ThreadFactory() {
 public Thread newThread(Runnable r) {
 Thread t = Executors.defaultThreadFactory().newThread(r);
 t.setDaemon(true);
 return t;
 }
 });

exec.execute(YourTaskNowWillBeDaemon);
</code></pre>
<hr />
But if you want to get executor which will let its task finish, and at the same time will automatically call its <code>shutdown()</code> method when application is complete, you may want to wrap your executor with <a href="https://github.com/google/guava" rel="noreferrer">Guava's</a> <a href="https://google.github.io/guava/releases/snapshot-jre/api/docs/com/google/common/util/concurrent/MoreExecutors.html#getExitingExecutorService-java.util.concurrent.ThreadPoolExecutor-long-java.util.concurrent.TimeUnit-" rel="noreferrer"><code>MoreExecutors.getExitingExecutorService</code></a>.
<pre><code>ExecutorService exec = MoreExecutors.getExitingExecutorService(
 (ThreadPoolExecutor) Executors.newFixedThreadPool(4), 
 100_000, TimeUnit.DAYS//period after which executor will be automatically closed
 //I assume that 100_000 days is enough to simulate infinity
);
//exec.execute(YourTask);
exec.execute(() -&gt; {
 for (int i = 0; i &lt; 3; i++) {
 System.out.println(&quot;daemon&quot;);
 try {
 TimeUnit.SECONDS.sleep(1);
 } catch (Exception e) {
 e.printStackTrace();
 }
 }
});
</code></pre>

blocks|key|417318|text|我会使用Guava的ThreadFactoryBuilder类。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|417319|ExecutorService+threadPool+=+Executors.newFixedThreadPool(THREADS,+new+ThreadFactoryBuilder().setDaemon(true).build());|code-block|syntax|javascript|417320|如果您还没有使用Guava，我会使用Pshemo's+answer顶部描述的ThreadFactory子类|offset|length|417321|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/13883412/1024576^0|0|0|I|F|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

I would use Guava's ThreadFactoryBuilder class.

<pre><code>ExecutorService threadPool = Executors.newFixedThreadPool(THREADS, new ThreadFactoryBuilder().setDaemon(true).build());
</code></pre>

If you're not already using Guava, I'd go with a ThreadFactory subclass like described at the top of <a href="https://stackoverflow.com/a/13883412/1024576">Pshemo's answer</a>

blocks|key|417356|text|如果您有一个已知的任务列表，则根本不需要守护进程线程。在提交所有任务之后，您可以简单地在ExecutorService上调用shutdown()。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|417357|当您的主线程完成时，使用awaitTermination()方法为提交的任务留出时间complete.The当前提交的任务将被执行，并且线程池将在它们完成后终止其控制线程。|417358|for+(Runnable+task+:+tasks)+{
++threadPool.submit(task);
}
threadPool.shutdown();
/*...+do+other+stuff+...*/
//All+done,+ready+to+exit
while+(!threadPool.isTerminated())+{
++//this+can+throw+InterruptedException,+you'll+need+to+decide+how+to+deal+with+that.
++threadPool.awaitTermination(1,TimeUnit.SECOND);+
}|code-block|syntax|javascript|417359|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

If you have a known list of tasks, you don't need daemon threads at all. You can simply call shutdown() on the ExecutorService after submitting all your tasks. 

When your main thread is complete, use the awaitTermination() method to allow time for the submitted tasks to complete.The currently submitted tasks will be executed, and the thread pool will terminate its control thread once they have been completed. 

<pre><code>for (Runnable task : tasks) {
 threadPool.submit(task);
}
threadPool.shutdown();
/*... do other stuff ...*/
//All done, ready to exit
while (!threadPool.isTerminated()) {
 //this can throw InterruptedException, you'll need to decide how to deal with that.
 threadPool.awaitTermination(1,TimeUnit.SECOND); 
}
</code></pre>

blocks|key|417406|text|这个解决方案类似于@marco13的解决方案，但是我们可以修改Executors#newFixedThreadPool(int+nThreads)返回的ThreadPoolExecutor，而不是创建我们自己的own。下面是操作步骤：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|417407|ExecutorService+ex+=+Executors.newFixedThreadPool(nThreads);
+if(ex+instanceof+ThreadPoolExecutor){
++++ThreadPoolExecutor+tp+=+(ThreadPoolExecutor)+ex;
++++tp.setKeepAliveTime(time,+timeUnit);
++++tp.allowCoreThreadTimeOut(true);
}|code-block|syntax|javascript|417408|entityMap^0|V|16|24|I|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

This solution is similar to @Marco13's but instead of creating our own <code>ThreadPoolExecutor</code>, we can modify the one returned by <code>Executors#newFixedThreadPool(int nThreads)</code>. Here's how:

<pre><code>ExecutorService ex = Executors.newFixedThreadPool(nThreads);
 if(ex instanceof ThreadPoolExecutor){
 ThreadPoolExecutor tp = (ThreadPoolExecutor) ex;
 tp.setKeepAliveTime(time, timeUnit);
 tp.allowCoreThreadTimeOut(true);
}
</code></pre>

blocks|key|417450|text|你可以使用芭乐的ThreadFactoryBuilder。我不想添加依赖项，而是想要来自Executors.DefaultThreadFactory的功能，所以我使用了组合：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|417451|class+DaemonThreadFactory+implements+ThreadFactory+{
++++final+ThreadFactory+delegate;

++++DaemonThreadFactory()+{
++++++++this(Executors.defaultThreadFactory());
++++}

++++DaemonThreadFactory(ThreadFactory+delegate)+{
++++++++this.delegate+=+delegate;
++++}

++++@Override
++++public+Thread+newThread(Runnable+r)+{
++++++++Thread+thread+=+delegate.newThread(r);
++++++++thread.setDaemon(true);
++++++++return+thread;
++++}
}|code-block|syntax|javascript|417452|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can use Guava's ThreadFactoryBuilder. I didn't want to add the dependency and I wanted the functionality from Executors.DefaultThreadFactory, so I used composition:

<pre><code>class DaemonThreadFactory implements ThreadFactory {
 final ThreadFactory delegate;

 DaemonThreadFactory() {
 this(Executors.defaultThreadFactory());
 }

 DaemonThreadFactory(ThreadFactory delegate) {
 this.delegate = delegate;
 }

 @Override
 public Thread newThread(Runnable r) {
 Thread thread = delegate.newThread(r);
 thread.setDaemon(true);
 return thread;
 }
}
</code></pre>

I am using an ExecutoreService in Java 1.6, started simply by 

<pre><code>ExecutorService pool = Executors.newFixedThreadPool(THREADS). 
</code></pre>

When my main thread is finished (along with all the tasks processed by the thread pool), this pool will prevent my program from shutting down until I explicitly call

<pre><code>pool.shutdown();
</code></pre>

Can I avoid having to call this by somehow turning the internal thread managing used by this pool into a deamon thread? Or am I missing something here.

Turning an ExecutorService to daemon in Java

我使用的是Java1.6中的ExecutoreService，开始时只需ExecutorService pool = Executors.newFixedThreadPool(THREADS). 当我的主线程完成(以及线程池处理的所有任务)时，这个线程池将防止我的程序关闭，直到我显式地调用pool.shutdown()...

问在Java中将ExecutorService转换为守护进程
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