#vulnerable code 
                                @Override
    public void mount(final Router router) {
        final Class<?> clazz = ZeroAmbient.getPlugin(KEY_ROUTER);
        if (Values.ZERO == LOG_FLAG_START.getAndIncrement()) {
            LOGGER.info(Info.DY_DETECT, NAME);
        }
        if (null != clazz && Ut.isImplement(clazz, PlugRouter.class)) {
            final JsonObject config = uniform.read();
            final JsonObject routerConfig = Fn.getNull(new JsonObject(), () -> config.getJsonObject(KEY_ROUTER), config);
            if (Values.ONE == LOG_FLAG_END.getAndIncrement()) {
                LOGGER.info(Info.DY_FOUND, NAME, clazz.getName(), routerConfig.encode());
            }
            // Mount dynamic router
            final PlugRouter plugRouter = Fn.poolThread(Pool.PLUGS,
                    () -> Ut.instance(clazz));
            plugRouter.bind(vertxRef);
            plugRouter.mount(router, routerConfig);
        } else {
            if (Values.ONE == LOG_FLAG_END.getAndIncrement()) {
                LOGGER.info(Info.DY_SKIP, NAME,
                        Fn.getNull(null, () -> null == clazz ? null : clazz.getName(), clazz));
            }
        }
    } 
                            #location 16 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Override
    public void mount(final Router router) {
        final Class<?> clazz = ZeroAmbient.getPlugin(PlugRouter.KEY_ROUTER);
        if (Values.ZERO == LOG_FLAG_START.getAndIncrement()) {
            LOGGER.info(Info.DY_DETECT, NAME);
        }
        if (null != clazz && Ut.isImplement(clazz, PlugRouter.class)) {
            final JsonObject routerConfig = PlugRouter.config();
            if (Values.ONE == LOG_FLAG_END.getAndIncrement()) {
                LOGGER.info(Info.DY_FOUND, NAME, clazz.getName(), routerConfig.encode());
            }
            // Mount dynamic router
            final PlugRouter plugRouter = Fn.poolThread(Pool.PLUGS,
                    () -> Ut.instance(clazz));
            plugRouter.bind(this.vertxRef);
            plugRouter.mount(router, routerConfig);
        } else {
            if (Values.ONE == LOG_FLAG_END.getAndIncrement()) {
                LOGGER.info(Info.DY_SKIP, NAME,
                        Fn.getNull(null, () -> null == clazz ? null : clazz.getName(), clazz));
            }
        }
    }