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<h1 class="title is-size-3 is-size-4-mobile has-text-weight-normal">
一起学Java之线程池
</h1>
<div class="content">
<h3 id="前言"><a href="#前言" class="headerlink" title="前言"></a>前言</h3><p>在开发中我们会使用多线程来提高效率,<code>Java</code>中提供了线程池，线程池是运用场景最多的并发框架，可以这么说，几乎所有需要异步或者并发执行任务的程序都可以使用线程池。合理的使用线程池<a id="more"></a>可以降低资源消耗，提高响应速度，更加方便的管理线程。</p>
<h3 id="线程池主要的处理流程"><a href="#线程池主要的处理流程" class="headerlink" title="线程池主要的处理流程"></a>线程池主要的处理流程</h3><p>要想了解一件事，那么我们必须先了解这件事的流程，所以我们要了解一下线程池的主要处理流程。</p>
<ol>
<li>任务提交以后，线程池判断核心线程是否都在执行任务，如果没有，就新建一个线程来执行这个任务，如果有那么进入第二步。</li>
<li>线程池判断工作队列中是否已满，没有，就把这个队列存储到工作队列中去，如果满了，就执行第三步。</li>
<li>线程池判断线程池的线程是否都处于工作状态，如果没有，就创建一个线程来执行任务，如果已经满了，就按照策略处理无法执行的任务。</li>
<li>主要的处理流程见下图</li>
</ol>
<p><img src="/images/%E7%BA%BF%E7%A8%8B%E6%B1%A0%E7%9A%84%E5%A4%84%E7%90%86%E6%B5%81%E7%A8%8B.jpg" alt></p>
<h3 id="线程池的使用"><a href="#线程池的使用" class="headerlink" title="线程池的使用"></a>线程池的使用</h3><h4 id="线程池的创建"><a href="#线程池的创建" class="headerlink" title="线程池的创建"></a>线程池的创建</h4><p>下面我们来看下线程池的使用，在<code>Java</code>中我们可以通过<code>ThreadPoolExecutor</code>来创建一个线程池，初始化线程池的时候要有几个参数（基于jdk1.8），我们一起来看下</p>
<ol>
<li>corePoolSize： 这个参数表示线程池的基本大小，根据线程池的处理流程我们可以知道，当提交一个任务到线程池中的时候，线程池会创建一个线程来执行任务，这里需要注意一点，当线程池的基本大小没满的时候，不管线程池有没有空闲，他都会创建一个线程来执行，直到线程池的基本大小满了，就不在创建了，有的同学就会问了，能不能不在提交任务的时候创建呢，当然是可以的，线程池提供了一个prestartAllCoreThreads()的方法，调用这个方法以后，线程池会提前创建并启动所有基本线程。</li>
<li>maximumPoolSize： 这个参数表示线程池的最大数量，简单的来说就是线程池允许创建的最大的线程数量。如果工作队列满了，线程池就会新建一个线程来执行任务，但是有一点，如果任务队列的大小是无限大的时候，这个最大值就没有用了，因为不管你有多少任务，他都会进入到任务队列中去。</li>
<li>keepAliveTime： 线程的保活时间，就是在线程池中有一个工作线程空闲了，这个线程可以存活多长时间，如果每个任务的执行时间比较短的话，我们可以加大线程的保活时间，这样线程的利用率就提高了</li>
<li>unit： 线程保活的单位，详见TimeUnit，可以是天、小时、分钟、秒、毫秒、微妙、纳秒</li>
<li>workQueue： 工作队列，作用是用来保存等待执行任务的阻塞队列，阻塞队列有多种下面我们来一一看下<ul>
<li>ArrayBlockingQueue： 看名字是不是很熟悉，像不像<code>ArrayList</code>，通过名字我们可以看出，肯定是基于数据结构的，所以呢<code>ArrayBlockingQueue</code>是一个基于数据的，有界的（可以设置队列大小）阻塞队列，这个队列按照先进先出的原则对队列中的任务进行排序</li>
<li>LinkedBlockingQueue： 同理，这个一看就知道是基于链表的阻塞队列，这个队列也是按照先进先出原则进行排序，由于使用的是链表，插入删除效率高，所以吞吐量是要高于<code>ArrayBlockingQueue</code>的</li>
<li>SynchronousQueue：这个是一个不存储元素的阻塞队列，看名字就知道，同步，这表示每一个插入操作都必须等到另一个线程的移除操作，不然插入操作就会一直阻塞</li>
<li>PriorityBlockingQueue: 一个支持优先级的无界阻塞队列，直到系统资源耗尽，使用的较少。</li>
</ul>
</li>
<li>threadFactory：用来设置创建线程的工厂，一般的都使用<code>guava</code>提供的<code>ThreadFactoryBuilder</code>来创建，例如通过<code>ThreadFactoryBuilder</code>来给线程设置名字，方便后期查问题，代码示例： <figure class="highlight plain hljs"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br></pre></td><td class="code"><pre><span class="line">public static void main(String[] args) {</span><br><span class="line"> ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(2, 3, 0L, TimeUnit.MILLISECONDS,</span><br><span class="line"> new LinkedBlockingDeque<>(2),new ThreadFactoryBuilder().setNameFormat("hachi-test-%d").build());</span><br><span class="line"></span><br><span class="line"> threadPoolExecutttr.prestartAllCoreThreads();</span><br><span class="line"> for (int i = 0; i <3 ; i++ {</span><br><span class="line"> threadPoolExecutor.execute(new Runnable() {</span><br><span class="line"> @Override</span><br><span class="line"> public void run() {</span><br><span class="line"></span><br><span class="line"> System.out.println("线程"+ Thread.currentThread().getName()+"执行");</span><br><span class="line"> try {</span><br><span class="line"> TimeUnit.SECONDS.sleep(1L);</span><br><span class="line"> } catch (InterruptedException e) {</span><br><span class="line"> e.printStackTrace();</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"> });</span><br><span class="line"> }</span><br><span class="line"></span><br><span class="line">}</span><br></pre></td></tr></table></figure>
</li>
</ol>
<p>输出示例：</p>
<figure class="highlight plain hljs"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br></pre></td><td class="code"><pre><span class="line">线程hachi-test-2执行</span><br><span class="line">线程hachi-test-0执行</span><br><span class="line">线程hachi-test-1执行</span><br></pre></td></tr></table></figure>
<ol start="7">
<li><p>handler: 表示当队列已经饱和的时候使用的策略，类型为：<code>RejectedExecutionHandler</code>即如果队列和线程池都满了就需要一种策略来处理新加入的任务。jdk提供了4钟策略来处理这种情况</p>
<ul>
<li><p>AbortPolicy：直接抛出异常，这也是<code>ThreadPoolExecutor</code>默认的策略</p>
</li>
<li><p>CallerRunsPolicy: 只要线程池未关闭，就用调用者所在的线程来执行任务，这样做的好处是可以不用丢弃任务，坏处是可能导致调用者线程的性能急剧下降</p>
</li>
<li><p>DiscardOldestPolicy: 这个就比较流氓了，当任务进来的时候，直接丢去队列里面最近的一个任务，并执行当前任务。</p>
</li>
<li><p>DiscardPolicy:不处理,丢弃掉。</p>
</li>
<li><p>通过查看jdk 源码来看上述四种策略都是在<code>ThreadPoolExecutor</code>中的静态内部类，详细代码如下</p>
<figure class="highlight plain hljs"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br><span class="line">33</span><br><span class="line">34</span><br><span class="line">35</span><br><span class="line">36</span><br><span class="line">37</span><br><span class="line">38</span><br><span class="line">39</span><br><span class="line">40</span><br><span class="line">41</span><br><span class="line">42</span><br><span class="line">43</span><br><span class="line">44</span><br><span class="line">45</span><br><span class="line">46</span><br><span class="line">47</span><br><span class="line">48</span><br><span class="line">49</span><br><span class="line">50</span><br><span class="line">51</span><br><span class="line">52</span><br><span class="line">53</span><br><span class="line">54</span><br><span class="line">55</span><br><span class="line">56</span><br><span class="line">57</span><br><span class="line">58</span><br><span class="line">59</span><br><span class="line">60</span><br><span class="line">61</span><br><span class="line">62</span><br><span class="line">63</span><br><span class="line">64</span><br><span class="line">65</span><br><span class="line">66</span><br><span class="line">67</span><br><span class="line">68</span><br><span class="line">69</span><br><span class="line">70</span><br><span class="line">71</span><br><span class="line">72</span><br><span class="line">73</span><br><span class="line">74</span><br><span class="line">75</span><br><span class="line">76</span><br><span class="line">77</span><br><span class="line">78</span><br><span class="line">79</span><br><span class="line">80</span><br><span class="line">81</span><br><span class="line">82</span><br><span class="line">83</span><br><span class="line">84</span><br><span class="line">85</span><br><span class="line">86</span><br><span class="line">87</span><br><span class="line">88</span><br><span class="line">89</span><br><span class="line">90</span><br><span class="line">91</span><br><span class="line">92</span><br><span class="line">93</span><br><span class="line">94</span><br><span class="line">95</span><br><span class="line">96</span><br><span class="line">97</span><br></pre></td><td class="code"><pre><span class="line"> /**</span><br><span class="line"> * A handler for rejected tasks that runs the rejected task</span><br><span class="line"> * directly in the calling thread of the {@code execute} method,</span><br><span class="line"> * unless the executor has been shut down, in which case the task</span><br><span class="line"> * is discarded.</span><br><span class="line"> */</span><br><span class="line">public static class CallerRunsPolicy implements RejectedExecutionHandler {</span><br><span class="line"> /**</span><br><span class="line"> * Creates a {@code CallerRunsPolicy}.</span><br><span class="line"> */</span><br><span class="line"> public CallerRunsPolicy() { }</span><br><span class="line"></span><br><span class="line"> /**</span><br><span class="line"> * Executes task r in the caller's thread, unless the executor</span><br><span class="line"> * has been shut down, in which case the task is discarded.</span><br><span class="line"> *</span><br><span class="line"> * @param r the runnable task requested to be executed</span><br><span class="line"> * @param e the executor attempting to execute this task</span><br><span class="line"> */</span><br><span class="line"> public void rejectedExecution(Runnable r, ThreadPoolExecutor e) {</span><br><span class="line"> if (!e.isShutdown()) {</span><br><span class="line"> r.run();</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line">/**</span><br><span class="line"> * A handler for rejected tasks that throws a</span><br><span class="line"> * {@code RejectedExecutionException}.</span><br><span class="line"> */</span><br><span class="line">public static class AbortPolicy implements RejectedExecutionHandler {</span><br><span class="line"> /**</span><br><span class="line"> * Creates an {@code AbortPolicy}.</span><br><span class="line"> */</span><br><span class="line"> public AbortPolicy() { }</span><br><span class="line"></span><br><span class="line"> /**</span><br><span class="line"> * Always throws RejectedExecutionException.</span><br><span class="line"> *</span><br><span class="line"> * @param r the runable task requested to be executed</span><br><span class="line"> * @param e the execuutor attempting to execute this task</span><br><span class="line"> * @throws RejectedExecutionException always</span><br><span class="line"> */</span><br><span class="line"> public void rejectedExecution(Runnable r, ThreadPoolExecutor e) {</span><br><span class="line"> throw new RejectedExecutionException("Task " + r.toString() +</span><br><span class="line"> " rejected from " +</span><br><span class="line"> e.toString());</span><br><span class="line"> }</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line">/**</span><br><span class="line"> * A handler for rejected tasks that silently discards the</span><br><span class="line"> * rejected task.</span><br><span class="line"> */</span><br><span class="line">public static class DiscardPolicy implements RejectedExecutionHandler {</span><br><span class="line"> /**</span><br><span class="line"> * Creates a {@code DiscardPolicy}.</span><br><span class="line"> */</span><br><span class="line"> public DiscardPolicy() { }</span><br><span class="line"></span><br><span class="line"> /**</span><br><span class="line"> * Does nothing, which has the effect of discarding task r.</span><br><span class="line"> *</span><br><span class="line"> * @param r the runnable task requested toe executed</span><br><span class="line"> * @param e the executor attempting to execuuute this task</span><br><span class="line"> */</span><br><span class="line"> public void rejectedExecution(Runnable r, ThreadPoolExecutor e) {</span><br><span class="line"> }</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line">/**</span><br><span class="line"> * A handler for rejected tasks that discards the oldest unhandled</span><br><span class="line"> * request and then retries {@code execute}, unless the executor</span><br><span class="line"> * is shut down, in which case the task is discarded.</span><br><span class="line"> */</span><br><span class="line">public static class DiscardOldestPolicy implements RejectedExecutionHandler {</span><br><span class="line"> /**</span><br><span class="line"> * Creates a {@code DiscardOldestPolicy} for the given executor.</span><br><span class="line"> */</span><br><span class="line"> public DiscardOldestPolicy() { }</span><br><span class="line"></span><br><span class="line"> /**</span><br><span class="line"> * Obtains and ignores the next task that the executor</span><br><span class="line"> * would otherwise execute, if one is immediately available,</span><br><span class="line"> * and then retries execution of task r, unless the executor</span><br><span class="line"> * is shut down, in which case task r is instead discarded.</span><br><span class="line"> *</span><br><span class="line"> * @param r the runnable task requested to be executed</span><br><span class="line"> * @param e the executor attempting to execute this task</span><br><span class="line"> */</span><br><span class="line"> public void rejectedExecution(Runnable r, ThreadPoolExecutor e) {</span><br><span class="line"> if (!e.isShutdown()) {</span><br><span class="line"> e.getQueue().poll();</span><br><span class="line"> e.execute(r);</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line">}</span><br></pre></td></tr></table></figure>
<p>所以我们也可以手动实现<code>RejectedExecutionHandler</code>接口来自定义策略，例如记录log，或者任务重启机制等</p>
</li>
</ul>
</li>
</ol>
<h4 id="向线程池中提交任务"><a href="#向线程池中提交任务" class="headerlink" title="向线程池中提交任务"></a>向线程池中提交任务</h4><p>在<code>ThreadPoolExecutor</code>中提供了两种方法想线程池中提交任务，分别是execute()和submit()。下面我们来了解一下这个方法</p>
<ol>
<li><p>execute： 通过查看jdk源码我们不难发现<code>execute</code>方法的入参是一个Runnable()对象，但是是没有回参的所以我们无法判断任务是否被线程池执行成功。示例代码：</p>
<figure class="highlight plain hljs"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br></pre></td><td class="code"><pre><span class="line">threadPoolExecutor.execute(new Runnable() {</span><br><span class="line"> @Override</span><br><span class="line"> public void run() {</span><br><span class="line"></span><br><span class="line"> System.out.println("线程"+ Thread.currentThread().getName()+"执行");</span><br><span class="line"> try {</span><br><span class="line"> TimeUnit.SECONDS.sleep(1L);</span><br><span class="line"> } catch (InterruptedException e) {</span><br><span class="line"> e.printStackTrace();</span><br><span class="line"> }</span><br><span class="line"> }</span><br><span class="line"> });</span><br></pre></td></tr></table></figure>
</li>
<li><p>submit: 通过查看jdk源码我们可以发现 submit方法是来源于接口<code>ExecutorService</code>，<code>AbstractExecutorService</code>实现了<code>ExecutorService</code>，<code>ThreadPoolExecutor</code>继承了<code>AbstractExecutorService</code>。 这个方法是可以返回一个Future类型，通过这个回参的get()方法可以获取返回值。</p>
<ul>
<li>get()方法会阻塞当前线程直到任务完成</li>
<li>get(long timeout,TimeUnit unit)会根据传入的时间来阻塞一段时间然后立即返回，这个时候任务很可能未完成 </li>
</ul>
</li>
</ol>
<p>下面我们看下<code>submit</code>方法的代码</p>
<figure class="highlight plain hljs"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br><span class="line">19</span><br><span class="line">20</span><br><span class="line">21</span><br><span class="line">22</span><br><span class="line">23</span><br><span class="line">24</span><br><span class="line">25</span><br><span class="line">26</span><br><span class="line">27</span><br><span class="line">28</span><br><span class="line">29</span><br><span class="line">30</span><br><span class="line">31</span><br><span class="line">32</span><br></pre></td><td class="code"><pre><span class="line">/**</span><br><span class="line"> * @throws RejectedExecutionException {@inheritDoc}</span><br><span class="line"> * @throws NullPointerException {@inheritDoc}</span><br><span class="line"> */</span><br><span class="line">public Future<?> submit(Runnable task) {</span><br><span class="line"> if (task == null) throw new NullPointerException();</span><br><span class="line"> RunnableFuture<Void> ftask = newTaskFor(task, null);</span><br><span class="line"> execute(ftask);</span><br><span class="line"> return ftask;</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line">/**</span><br><span class="line"> * @throws RejectedExecutionException {@inheritDoc}</span><br><span class="line"> * @throws NullPointerException {@inheritDoc}</span><br><span class="line"> */</span><br><span class="line">public <T> Future<T> submit(Runnable task, T result) {</span><br><span class="line"> if (task == null) throw new NullPointerException();</span><br><span class="line"> RunnableFuture<T> ftask = newTaskFor(task, result);</span><br><span class="line"> execute(ftask);</span><br><span class="line"> return ftask;</span><br><span class="line">}</span><br><span class="line"></span><br><span class="line">/**</span><br><span class="line"> * @throws RejectedExecutionException {@inheritDoc}</span><br><span class="line"> * @throws NullPointerException {@inheritDoc}</span><br><span class="line"> */</span><br><span class="line">public <T> Future<T> submit(Callable<T> task) {</span><br><span class="line"> if (task == null) throw new NullPointerException();</span><br><span class="line"> RunnableFuture<T> ftask = newTaskFor(task);</span><br><span class="line"> execute(ftask);</span><br><span class="line"> return ftask;</span><br><span class="line">}</span><br></pre></td></tr></table></figure>
<p>可以看到有三个submit方法。但是只有实现了<code>Callable</code>接口才能有返回值， <code>Runnable</code>是没有的，即<code>submit(Runnable task)</code>返回的值调用get方法后会返回一个<code>null</code>。而<code>submit(Runnable task, T result)</code>能通过传入的载体<code>result</code>间接获得线程的返回值，如果执行失败就会获取到异常，如果执行成功就会拿到之前定义好的值<br>下面我们介绍一下<code>submit(Callable<T> task)</code> 示例代码详见： </p>
<figure class="highlight plain hljs"><table><tr><td class="gutter"><pre><span class="line">1</span><br><span class="line">2</span><br><span class="line">3</span><br><span class="line">4</span><br><span class="line">5</span><br><span class="line">6</span><br><span class="line">7</span><br><span class="line">8</span><br><span class="line">9</span><br><span class="line">10</span><br><span class="line">11</span><br><span class="line">12</span><br><span class="line">13</span><br><span class="line">14</span><br><span class="line">15</span><br><span class="line">16</span><br><span class="line">17</span><br><span class="line">18</span><br></pre></td><td class="code"><pre><span class="line">public static void main(String[] args) throws ExecutionException, InterruptedException {</span><br><span class="line"> ThreadPoolExecutor threadPoolExecutor = new ThreadPoolExecutor(2, 3, 0L, TimeUnit.MILLISECONDS,</span><br><span class="line"> new LinkedBlockingDeque<>(2),new ThreadFactoryBuilder().setNameFormat("hachi-test-%d").build());</span><br><span class="line"></span><br><span class="line"> threadPoolExecutor.prestartAllCoreThreads();</span><br><span class="line"></span><br><span class="line"> for (int i = 0; i <3 ; i++) {</span><br><span class="line"> Callable<HttpClientResultBean> callable = new Callable<HttpClientResultBean>() {</span><br><span class="line"> public HttpClientResultBean call() throws Exception {</span><br><span class="line"> System.out.println("线程"+ Thread.currentThread().getName()+"执行");</span><br><span class="line"> return new HttpClientResultBean();</span><br><span class="line"> }</span><br><span class="line"> };</span><br><span class="line"> Future<HttpClientResultBean> future= threadPoolExecutor.submit(callable);</span><br><span class="line"> System.out.println(JsonUtils.obj2Json(future.get()));</span><br><span class="line"> }</span><br><span class="line"></span><br><span class="line">}</span><br></pre></td></tr></table></figure>
<h4 id="关闭线程池"><a href="#关闭线程池" class="headerlink" title="关闭线程池"></a>关闭线程池</h4><p>通过上述操作我们创建了线程池，并且向线程池中新增了任务，那么我们如何关闭线程池呢？jdk提供了<code>shutdown</code>和<code>shutdownNow</code>两个方法来关闭线程池。原理是遍历线程池中的工作线程,然后逐个调用线程的interrupt方法来中断线程,所以无法响应中断的任务<br>可能永远无法终止。那么他们有啥区别呢？</p>
<ol>
<li>shutdown： 仅仅是将线程池的状态设置成<code>SHUTDOWN</code>状态，然后中断没有正在执行的任务线程</li>
<li>shutdownNow：首先将线程池的状态设置成｀STOP｀,然后尝试停止所有的正在执行或暂停任务的线程,并返回等待执行任务的列表</li>
</ol>
<p>注意：</p>
<ul>
<li>只要调用了两个方法的任意一个,<code>isShutdown</code>方法就会返回<code>true</code>。当所有的任务<br>都已关闭后,才表示线程池关闭成功,这时调用<code>isTerminaed</code>方法会返回<code>true</code>。至于应该调用哪<br>一种方法来关闭线程池,应该由提交到线程池的任务特性决定,通常调用<code>shutdown</code>方法来关闭<br>线程池,如果任务不一定要执行完,则可以调用<code>shutdownNow</code>方法。</li>
</ul>
</div>
<ul class="post-copyright">
<li><strong>本文标题：</strong><a href="https://blog.visutech.cn/1392887984.html">一起学Java之线程池</a></li>
<li><strong>本文作者：</strong><a href="https://blog.visutech.cn">程振奇 | smallodd</a></li>
<li><strong>本文链接：</strong><a href="https://blog.visutech.cn/1392887984.html">https://blog.visutech.cn/1392887984.html</a></li>
<li><strong>发布时间：</strong>2019-04-23</li>
<li><strong>版权声明：</strong>本博客所有文章除特别声明外，均采用 <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/deed.zh" rel="external nofollow" target="_blank">CC BY-NC-SA 4.0</a> 许可协议。转载请注明出处！
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<a class="is-flex" href="#线程池主要的处理流程">
<span class="has-mr-6">2</span>
<span>线程池主要的处理流程</span>
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<a class="is-flex" href="#线程池的使用">
<span class="has-mr-6">3</span>
<span>线程池的使用</span>
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<a class="is-flex" href="#线程池的创建">
<span class="has-mr-6">3.1</span>
<span>线程池的创建</span>
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<a class="is-flex" href="#向线程池中提交任务">
<span class="has-mr-6">3.2</span>
<span>向线程池中提交任务</span>
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<a class="is-flex" href="#关闭线程池">
<span class="has-mr-6">3.3</span>
<span>关闭线程池</span>
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