@Override
    protected List<Traversal> getTraversals() {
        return Arrays.asList(
                __.addE("knows").property("a", "b"),
                __.addE("created").property("a", "b"),
                __.addE("knows").property("a", "b").property("c", "d"),
                __.addE("knows").property("c", "d")
        );
    }
@author Daniel Kuppitz (http://gremlin.guru)
gremlin-core/src/test/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/AddEdgeStepTest.java