public static String getSharedSecret()
    {
        if ( !isSharedSecretAllowed() )
        {
            return null;
        }

        String sharedSecret = JiveGlobals.getProperty( "xmpp.auth.sharedSecret" );
        if ( sharedSecret == null )
        {
            sharedSecret = StringUtils.randomString( 8 );
            JiveGlobals.setProperty( "xmpp.auth.sharedSecret", sharedSecret );
        }
        return sharedSecret;
    }
Returns the shared secret value, or {@code null} if shared secret authentication is disabled. If this is the
first time the shared secret value has been requested (and  shared secret auth is enabled), the key will be
randomly generated and stored in the property {@code xmpp.auth.sharedSecret}.

@return the shared secret value.
xmppserver/src/main/java/org/jivesoftware/openfire/sasl/JiveSharedSecretSaslServer.java