title: JSF f:ajax listener vs commandButton action
body: <p>I'm curious what is the difference between these two ways of executing ajax calls:</p>
  
  <pre><code>&lt;h:commandButton value="Submit" action="#{bean.action}"&gt;
     &lt;f:ajax execute="@form" render="component"/&gt;
  &lt;/h:commandButton&gt;
  </code></pre>
  
  <p>and </p>
  
  <pre><code>&lt;h:commandButton value="Submit"&gt;
     &lt;f:ajax listener="#{bean.action}" execute="@form" render="component"/&gt;
  &lt;/h:commandButton&gt;
  </code></pre>
  
  <p>It appears that people use the first way more often, but the second seems to work just fine as well...</p>