blocks|key|983613|text|如果要等待所有任务完成，请使用shutdown方法而不是wait。然后使用awaitTermination跟踪它。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|983614|此外，您还可以使用Runtime.availableProcessors来获取硬件线程的数量，以便正确地初始化线程池。|983615|entityMap|0|LINK|mutability|MUTABLE|url|http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html#shutdown--|1|http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html#awaitTermination-long-java.util.concurrent.TimeUnit-|2|http://docs.oracle.com/javase/8/docs/api/java/lang/Runtime.html#availableProcessors--^0|F|8|S|4|11|G|F|8|0|11|G|1|0|9|R|9|R|2|0^^$0|@$1|2|3|4|5|6|7|T|8|@$9|U|A|V|B|C]|$9|W|A|X|B|C]|$9|Y|A|Z|B|C]]|D|@$9|10|A|11|1|12]|$9|13|A|14|1|15]]|E|$]]|$1|F|3|G|5|6|7|16|8|@$9|17|A|18|B|C]]|D|@$9|19|A|1A|1|1B]]|E|$]]|$1|H|3|-4|5|6|7|1C|8|@]|D|@]|E|$]]]|I|$J|$5|K|L|M|E|$N|O]]|P|$5|K|L|M|E|$N|Q]]|R|$5|K|L|M|E|$N|S]]]]

If you want to wait for all tasks to complete, use the <a href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html#shutdown--" rel="noreferrer"><code>shutdown</code></a> method instead of <code>wait</code>. Then follow it with <a href="http://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html#awaitTermination-long-java.util.concurrent.TimeUnit-" rel="noreferrer"><code>awaitTermination</code></a>. 

Also, you can use <a href="http://docs.oracle.com/javase/8/docs/api/java/lang/Runtime.html#availableProcessors--" rel="noreferrer"><code>Runtime.availableProcessors</code></a> to get the number of hardware threads so you can initialize your threadpool properly.

blocks|key|1198210|text|如果您想等待executor服务完成执行，请调用shutdown()，然后调用awaitTermination(units,+unitType)，例如awaitTermination(1,+MINUTE)。ExecutorService不会在它自己的监视器上阻塞，所以你不能使用wait等。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1198211|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html#awaitTermination-long-java.util.concurrent.TimeUnit-^0|O|A|23|R|3V|4|13|X|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@$9|O|A|P|B|C]|$9|Q|A|R|B|C]|$9|S|A|T|B|C]]|D|@$9|U|A|V|1|W]]|E|$]]|$1|F|3|-4|5|6|7|X|8|@]|D|@]|E|$]]]|G|$H|$5|I|J|K|E|$L|M]]]]

If you want to wait for the executor service to finish executing, call <code>shutdown()</code> and then, <a href="https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ExecutorService.html#awaitTermination-long-java.util.concurrent.TimeUnit-" rel="noreferrer">awaitTermination(units, unitType)</a>, e.g. <code>awaitTermination(1, MINUTE)</code>. The ExecutorService does not block on it's own monitor, so you can't use <code>wait</code> etc.

blocks|key|983952|text|只需使用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|983953|latch+=+new+CountDownLatch(noThreads)|code-block|syntax|javascript|983954|在每个线程中|983955|latch.countDown();|983956|以及作为屏障|983957|latch.await();|983958|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

Just use 

<pre><code>latch = new CountDownLatch(noThreads)
</code></pre>

In each thread 

<pre><code>latch.countDown();
</code></pre>

and as barrier

<pre><code>latch.await();
</code></pre>

blocks|key|1198578|text|你可以使用ExecutorService.invokeAll方法，它将执行所有任务，并等待所有线程完成任务。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1198579|下面是完整的javadoc|1198580|您还可以使用此方法的重载版本来指定超时。|1198581|下面是使用ExecutorService.invokeAll编写的示例代码|1198582|public+class+Test+{
++++public+static+void+main(String[]+args)+throws+InterruptedException,+ExecutionException+{
++++++++ExecutorService+service+=+Executors.newFixedThreadPool(3);
++++++++List<Callable<String>>+taskList+=+new+ArrayList<>();
++++++++taskList.add(new+Task1());
++++++++taskList.add(new+Task2());
++++++++List<Future<String>>+results+=+service.invokeAll(taskList);
++++++++for+(Future<String>+f+:+results)+{
++++++++++++System.out.println(f.get());
++++++++}
++++}

}

class+Task1+implements+Callable<String>+{
++++@Override
++++public+String+call()+throws+Exception+{
++++++++try+{
++++++++++++Thread.sleep(2000);
++++++++++++return+"Task+1+done";
++++++++}+catch+(Exception+e)+{
++++++++++++e.printStackTrace();
++++++++++++return+"+error+in+task1";
++++++++}
++++}
}

class+Task2+implements+Callable<String>+{
++++@Override
++++public+String+call()+throws+Exception+{
++++++++try+{
++++++++++++Thread.sleep(3000);
++++++++++++return+"Task+2+done";
++++++++}+catch+(Exception+e)+{
++++++++++++e.printStackTrace();
++++++++++++return+"+error+in+task2";
++++++++}
++++}
}|code-block|syntax|javascript|1198583|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ExecutorService.html#invokeAll(java.util.Collection)^0|5|P|0|6|7|0|0|0|5|P|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|11|8|@]|D|@$9|12|A|13|1|14]]|E|$]]|$1|H|3|I|5|6|7|15|8|@]|D|@]|E|$]]|$1|J|3|K|5|6|7|16|8|@$9|17|A|18|B|C]]|D|@]|E|$]]|$1|L|3|M|5|N|7|19|8|@]|D|@]|E|$O|P]]|$1|Q|3|-4|5|6|7|1A|8|@]|D|@]|E|$]]]|R|$S|$5|T|U|V|E|$W|X]]]]

You can use <code>ExecutorService.invokeAll</code> method, It will execute all task and wait till all threads finished their task.

Here is complete <a href="https://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ExecutorService.html#invokeAll(java.util.Collection)" rel="noreferrer">javadoc</a>

You can also user overloaded version of this method to specify the timeout.

Here is sample code with <code>ExecutorService.invokeAll</code>

<pre><code>public class Test {
 public static void main(String[] args) throws InterruptedException, ExecutionException {
 ExecutorService service = Executors.newFixedThreadPool(3);
 List&lt;Callable&lt;String&gt;&gt; taskList = new ArrayList&lt;&gt;();
 taskList.add(new Task1());
 taskList.add(new Task2());
 List&lt;Future&lt;String&gt;&gt; results = service.invokeAll(taskList);
 for (Future&lt;String&gt; f : results) {
 System.out.println(f.get());
 }
 }

}

class Task1 implements Callable&lt;String&gt; {
 @Override
 public String call() throws Exception {
 try {
 Thread.sleep(2000);
 return "Task 1 done";
 } catch (Exception e) {
 e.printStackTrace();
 return " error in task1";
 }
 }
}

class Task2 implements Callable&lt;String&gt; {
 @Override
 public String call() throws Exception {
 try {
 Thread.sleep(3000);
 return "Task 2 done";
 } catch (Exception e) {
 e.printStackTrace();
 return " error in task2";
 }
 }
}
</code></pre>

blocks|key|983768|text|我还有一种情况，那就是我有一组文档要抓取。我从应该处理的初始“种子”文档开始，该文档包含到也应该处理的其他文档的链接，等等。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|983769|在我的主程序中，我只想编写类似下面这样的代码，其中Crawler控制一堆线程。|offset|length|style|CODE|983770|Crawler+c+=+new+Crawler();
c.schedule(seedDocument);+
c.waitUntilCompletion()|code-block|syntax|javascript|983771|如果我想浏览一棵树，同样的情况也会发生；我将弹出根节点，每个节点的处理器会根据需要将子节点添加到队列中，一堆线程将处理树中的所有节点，直到没有更多的节点为止。|983772|我在JVM中找不到任何东西，我认为这有点令人惊讶。所以我写了一个类ThreadPool，你可以直接使用它或者子类来添加适合这个领域的方法，比如schedule(Document)。希望它能帮上忙！|983773|ThreadPool+Javadoc+%7C+Maven|983774|entityMap|0|LINK|mutability|MUTABLE|url|https://javadoc.databasesandlife.com/com/databasesandlife/util/ThreadPool.html|1|https://mvnrepository.com/artifact/com.databasesandlife/java-common^0|0|P|7|0|0|0|X|A|1Z|I|0|0|I|0|L|5|1|0^^$0|@$1|2|3|4|5|6|7|12|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|13|8|@$D|14|E|15|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|16|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|17|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|18|8|@$D|19|E|1A|F|G]|$D|1B|E|1C|F|G]]|9|@]|A|$]]|$1|Q|3|R|5|6|7|1D|8|@]|9|@$D|1E|E|1F|1|1G]|$D|1H|E|1I|1|1J]]|A|$]]|$1|S|3|-4|5|6|7|1K|8|@]|9|@]|A|$]]]|T|$U|$5|V|W|X|A|$Y|Z]]|10|$5|V|W|X|A|$Y|11]]]]

I also have the situation that I have a set of documents to be crawled. I start with an initial &quot;seed&quot; document which should be processed, that document contains links to other documents which should also be processed, and so on.
In my main program, I just want to write something like the following, where <code>Crawler</code> controls a bunch of threads.
<pre><code>Crawler c = new Crawler();
c.schedule(seedDocument); 
c.waitUntilCompletion()
</code></pre>
The same situation would happen if I wanted to navigate a tree; i would pop in the root node, the processor for each node would add children to the queue as necessary, and a bunch of threads would process all the nodes in the tree, until there were no more.
I couldn't find anything in the JVM which I thought was a bit surprising. So I wrote a class <code>ThreadPool</code> which one can either use directly or subclass to add methods suitable for the domain, e.g. <code>schedule(Document)</code>. Hope it helps!
<a href="https://javadoc.databasesandlife.com/com/databasesandlife/util/ThreadPool.html" rel="nofollow noreferrer">ThreadPool Javadoc</a> | <a href="https://mvnrepository.com/artifact/com.databasesandlife/java-common" rel="nofollow noreferrer">Maven</a>

blocks|key|983916|text|添加集合中的所有线程，并使用invokeAll提交。如果您可以使用ExecutorService的invokeAll方法，那么在所有线程完成之前，JVM不会进入下一行。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|983917|这里有一个很好的例子：invokeAll+via+ExecutorService+|983918|entityMap|0|LINK|mutability|MUTABLE|url|http://jovialjava.blogspot.com.tr/2011/01/part-7-javautilconcurrent-invokeall-via.html^0|E|9|X|F|1D|9|0|B|U|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@$9|Q|A|R|B|C]|$9|S|A|T|B|C]|$9|U|A|V|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|W|8|@]|D|@$9|X|A|Y|1|Z]]|E|$]]|$1|H|3|-4|5|6|7|10|8|@]|D|@]|E|$]]]|I|$J|$5|K|L|M|E|$N|O]]]]

Add all threads in collection and submit it using <code>invokeAll</code>.
If you can use <code>invokeAll</code> method of <code>ExecutorService</code>, JVM won’t proceed to next line until all threads are complete.

Here there is a good example:
<a href="http://jovialjava.blogspot.com.tr/2011/01/part-7-javautilconcurrent-invokeall-via.html" rel="nofollow">invokeAll via ExecutorService </a>

blocks|key|1198396|text|我将等待executor以您认为适合完成任务的指定超时终止。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1198397|+try+{++
+++++++++//do+stuff+here+
+++++++++exe.execute(thread);
++++}+finally+{
++++++++exe.shutdown();
++++}
++++boolean+result+=+exe.awaitTermination(4,+TimeUnit.HOURS);
++++if+(!result)

++++{
++++++++LOGGER.error("It+took+more+than+4+hour+for+the+executor+to+stop,+this+shouldn't+be+the+normal+behaviour.");
++++}|code-block|syntax|javascript|1198398|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|$]]

I will just wait for the executor to terminate with a specified timeout that you think it is suitable for the tasks to complete.

<pre><code> try { 
 //do stuff here 
 exe.execute(thread);
 } finally {
 exe.shutdown();
 }
 boolean result = exe.awaitTermination(4, TimeUnit.HOURS);
 if (!result)

 {
 LOGGER.error("It took more than 4 hour for the executor to stop, this shouldn't be the normal behaviour.");
 }
</code></pre>

blocks|key|984093|text|这个怎么样？|type|unstyled|depth|inlineStyleRanges|entityRanges|data|984094|Object+lock+=+new+Object();
CountDownLatch+cdl+=+new+CountDownLatch(threadNum);
for+(int+i+=+0;+i+<+threadNum;+i%2B%2B)+{
++++executorService.execute(()+->+{

++++++++synchronized+(lock)+{
++++++++++++cdl.countDown();
++++++++++++try+{
++++++++++++++++lock.wait();
++++++++++++}+catch+(InterruptedException+e)+{
++++++++++++++++Thread.currentThread().interrupt();
++++++++++++}
++++++++}
++++});
}
cdl.await();
synchronized+(lock)+{
++++lock.notifyAll();
}|code-block|syntax|javascript|984095|如果不向ExecutorService添加新任务，则可能会等待所有当前任务完成|984096|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

how about this?
<pre class="lang-java prettyprint-override"><code>Object lock = new Object();
CountDownLatch cdl = new CountDownLatch(threadNum);
for (int i = 0; i &lt; threadNum; i++) {
 executorService.execute(() -&gt; {

 synchronized (lock) {
 cdl.countDown();
 try {
 lock.wait();
 } catch (InterruptedException e) {
 Thread.currentThread().interrupt();
 }
 }
 });
}
cdl.await();
synchronized (lock) {
 lock.notifyAll();
}
</code></pre>
if you do not add new tasks to ExecutorService , this may wait for all current tasks completed

blocks|key|983842|text|一种简单的替代方法是将线程与join一起使用。参考：Joining+Threads|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|983843|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/1908515/java-how-to-use-thread-join^0|Q|F|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

A simple alternative to this is to use threads along with join.
Refer : <a href="https://stackoverflow.com/questions/1908515/java-how-to-use-thread-join">Joining Threads</a>

What is the simplest way to to wait for all tasks of <code>ExecutorService</code> to finish? My task is primarily computational, so I just want to run a large number of jobs - one on each core. Right now my setup looks like this: 

<pre><code>ExecutorService es = Executors.newFixedThreadPool(2);
for (DataTable singleTable : uniquePhrases) { 
 es.execute(new ComputeDTask(singleTable));
}
try{
 es.wait();
} 
catch (InterruptedException e){
 e.printStackTrace();
}
</code></pre>

<code>ComputeDTask</code> implements runnable. This appears to execute the tasks correctly, but the code crashes on <code>wait()</code> with <code>IllegalMonitorStateException</code>. This is odd, because I played around with some toy examples and it appeared to work. 

<code>uniquePhrases</code> contains several tens of thousands of elements. Should I be using another method? I am looking for something as simple as possible

ExecutorService, how to wait for all tasks to finish

等待ExecutorService的所有任务完成的最简单方法是什么？我的任务主要是计算性的，所以我只想运行大量的作业-每个核心一个。现在，我的设置如下所示：ExecutorService es = Executors.newFixedThreadPool(2);for (DataTable singleTable : uniquePhrases) {       es.execute(new Co

问ExecutorService，如何等待所有任务完成
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