@Override
    public void serialize(final DirectionalStarGraph starGraph, final JsonGenerator jsonGenerator,
                          final SerializerProvider serializerProvider) throws IOException, JsonGenerationException {
        ser(starGraph, jsonGenerator, serializerProvider, null);
    }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/structure/util/star/StarGraphGraphSONSerializerV4.java