title: What's the purpose of async-supported in web.xml?
body: <pre class="lang-xml prettyprint-override"><code>&lt;servlet&gt;
          &lt;description&gt;xxx&lt;/description&gt;
          &lt;servlet-name&gt;xxx&lt;/servlet-name&gt;
          &lt;servlet-class&gt;com.xxx.yyy&lt;/servlet-class&gt;
          &lt;async-supported&gt;true&lt;/async-supported&gt;
  &lt;/servlet&gt;
  </code></pre>
  
  <p>What's the purpose of <code>async-supported</code> in the servlet's web.xml configuration file? What case I can use it in?</p>