public void outputGraph(final OutputStream jsonOutputStream, final Set<String> vertexPropertyKeys,
final Set<String> edgePropertyKeys, final GraphSONMode mode, final boolean normalize) throws IOException {
final JsonGenerator jg = jsonFactory.createGenerator(jsonOutputStream);
// don't let the JsonGenerator close the underlying stream...leave that to the client passing in the stream
jg.configure(JsonGenerator.Feature.AUTO_CLOSE_TARGET, false);
final GraphSONUtility graphson = new GraphSONUtility(mode, null,
ElementPropertyConfig.includeProperties(vertexPropertyKeys, edgePropertyKeys, normalize));
jg.writeStartObject();