red event.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>callback</code> - to call for the event notification</dd>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>self</dd>
</dl>
</li>
</ul>
<a id="async(boolean)">
<!--   -->
</a>
<ul class="blockListLast">
<li class="blockList">
<h4>async</h4>
<pre class="methodSignature"><a href="ObserverMethodConfigurator.html" title="interface in jakarta.enterprise.inject.spi.configurator">ObserverMethodConfigurator</a>&lt;<a href="Obs