title: What can <f:metadata>, <f:viewParam> and <f:viewAction> be used for?
body: <p>Can anyone clarify how we can use in general, or a in real world example, this snippet?</p>
  
  <pre><code>&lt;f:metadata&gt;
      &lt;f:viewParam id="id" value="#{bean.id}" /&gt;
      &lt;f:viewAction action="#{bean.init}" /&gt;
  &lt;/f:metadata&gt;
  </code></pre>