s.oracle.com/javase/8/docs/api/java/lang/annotation/ElementType.html?is-external=true#METHOD" title="class or interface in java.lang.annotation">METHOD</a>)
public @interface <span class="memberNameLabel">OnOpen</span></pre>
<div class="block">This method level annotation can be used to decorate a Java method that wishes to be called when a new web socket
 session is open.

 <p>
 The method may only take the following parameters:-
 <ul>
 <li>optional <a href="../../jakarta/websocket/Session.html" title="int