@Test
    @FeatureRequirement(featureClass = Graph.Features.EdgeFeatures.class, feature = Graph.Features.EdgeFeatures.FEATURE_ADD_EDGES)
    @FeatureRequirement(featureClass = Graph.Features.VertexFeatures.class, feature = Graph.Features.VertexFeatures.FEATURE_ADD_VERTICES)
    @FeatureRequirement(featureClass = Graph.Features.GraphFeatures.class, feature = Graph.Features.GraphFeatures.FEATURE_TRANSACTIONS)
    public void shouldRollbackElementAutoTransactionByDefault() {
        final Vertex v1 = graph.addVertex();
        final Edge e1 = v1.addEdge("l", v1);
        assertVertexEdgeCounts(graph, 1, 1);
        assertEquals(v1.id(), graph.vertices(v1.id()).next().id());
        assertEquals(e1.id(), graph.edges(e1.id()).next().id());
        g.tx().rollback();
        assertVertexEdgeCounts(graph, 0, 0);
    }
@author Stephen Mallette (http://stephen.genoprime.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/structure/TransactionTest.java