<p>Callback method invoked:</p>
<ul>
<li>for clients, just before the preface is sent, to gather the
SETTINGS configuration options the client wants to send to the server;</li>
<li>for servers, just after having received the preface, to gather
the SETTINGS configuration options the server wants to send to the
client.</li>
</ul>
@param session the session
@return a (possibly empty or null) map containing SETTINGS configuration
options to send.
<p>Callback method invoked:</p> <ul> <li>for clients, just before the preface is sent, to gather the SETTINGS configuration options the client wants to send to the server;</li> <li>for servers, just after having received the preface, to gather the SETTINGS configuration options the server wants to send to the client.</li> </ul>
@param session the session @return a (possibly empty or null) map containing SETTINGS configuration options to send.