sg = g.V().has('country', 'US').has('region',without('US-HI', 'US-AL')).outE('route').where(inV().has('region',without('US-HI', 'US-AL')).has('country', 'US')).subgraph('us').cap('us').next()
file = new FileOutputStream("/tmp/airroutes_us.json")
mapper = GraphSONMapper.build().addCustomModule(org.janusgraph.graphdb.tinkerpop.io.graphson.JanusGraphSONModuleV2d0.getInstance()).create()
writer = GraphSONWriter.build().mapper(mapper).create()
writer.writeGraph(file, sg)