@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)
        public void shouldHaveExceptionConsistencyWhenUsingEmptyVertexLabel() {
            final Vertex v = graph.addVertex();
            try {
                v.addEdge("", v);
                fail("Call to Vertex.addEdge() should throw an exception when label is empty");
            } catch (Exception ex) {
                validateException(Element.Exceptions.labelCanNotBeEmpty(), ex);
            }
        }
@author Stephen Mallette (http://stephen.genoprime.com)
@author Marko A. Rodriguez (http://markorodriguez.com)
gremlin-test/src/main/java/org/apache/tinkerpop/gremlin/structure/EdgeTest.java