@Override
    public String getAuthorizationID()
    {
        if ( !isComplete() )
        {
            throw new IllegalStateException( "Authentication exchange not completed." );
        }

        return authorizationID;
    }
This property controls if the inbound connection is required to provide an authorization identity in the SASL
EXTERNAL handshake (as part of an `auth` element). In older XMPP specifications, it was not required to have a
`from` attribute on the stream, making the authzid a required part of the handshake.

@see <a href="https://igniterealtime.atlassian.net/browse/OF-2639">Issue OF-2639</a>
xmppserver/src/main/java/org/jivesoftware/openfire/sasl/ExternalServerSaslServer.java