aging runtime. The
 CallbackHandler instance must be initialized with any application context needed to process the required callbacks on
 behalf of the corresponding application.</dd>
<dt>Returns:</dt>
<dd>A ClientAuthConfig Object that describes the configuration of ClientAuthModules at the message layer and
 messaging context identified by the layer and appContext arguments. This method does not return null.</dd>
<dt>Throws:</dt>
<dd><code><a href="../AuthException.html" title="class in jakarta.security.