@Override
    public GremlinScriptEngineFactory getFactory() {
        if (factory == null) {
            synchronized (this) {
                if (factory == null) {
                    factory = new GremlinLangScriptEngineFactory();
                }
            }
        }
        return this.factory;
    }
Creates a new instance using no {@link Customizer}.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/jsr223/GremlinLangScriptEngine.java