servlet.AsyncListener-"><code>AsyncContext.addListener(AsyncListener)</code></a>, this method must return null.</div>
<dl>
<dt><span class="returnLabel">Returns:</span></dt>
<dd>the ServletResponse that was used to initialize this AsyncEvent, or null if this AsyncEvent was initialized
 without any ServletResponse</dd>
</dl>
</li>
</ul>
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<h4>getThrowable</h4>
<pre>public&nbsp;<a href="https://docs.oracle.com/javase/8/d