public GraphTraversal<Vertex, Vertex> V(final Object... vertexIds) {
        // a single null is [null]
        final Object[] ids = null == vertexIds ? new Object[] { null } : vertexIds;
        final GraphTraversalSource clone = this.clone();
        clone.gremlinLang.addStep(GraphTraversal.Symbols.V, ids);
        final GraphTraversal.Admin<Vertex, Vertex> traversal = new DefaultGraphTraversal<>(clone);
        return traversal.addStep(new GraphStep<>(traversal, Vertex.class, true, ids));
    }
Spawns a {@link GraphTraversal} starting with all vertices or some subset of vertices as specified by their
unique identifier.

@since 3.0.0-incubating
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/dsl/graph/GraphTraversalSource.java