11/docs/api/java.base/java/lang/String.html?is-external=true" title="class or interface in java.lang" class="externalLink">String</a>&nbsp;onopen)</pre>
<div class="block">Sets the JavaScript event handler function that is invoked when the websocket is opened. The function will be invoked
 with one argument: the channel name.</div>
<dl>
<dt><span class="paramLabel">Parameters:</span></dt>
<dd><code>onopen</code> - The JavaScript event handler function that is invoked when the websocket is opened.</dd>
</dl>