public static JavaPairRDD<Object, VertexWritable> loadVertices(
        final InputRDD inputRDD,
        final org.apache.commons.configuration2.Configuration sparkGraphConfiguration,
        JavaSparkContext sparkContext) {
        JavaPairRDD<Object, VertexWritable> loadedGraphRDD = inputRDD.readGraphRDD(sparkGraphConfiguration, sparkContext);
        return loadedGraphRDD;
    }
Load graph into Spark RDDs

@param inputRDD                an InputRDD instance
@param sparkGraphConfiguration graph configurations
@param sparkContext            a JavaSparkContext instance
@return vertices in Spark RDD
spark-gremlin/src/main/java/org/apache/tinkerpop/gremlin/spark/structure/io/SparkIOUtil.java