@Override
    public List<Traversal.Admin<K, E>> getLocalChildren() {
        final List<Traversal.Admin<K, E>> result = new ArrayList<>();
        if (null != this.propertyTraversal)
            result.add((Traversal.Admin) propertyTraversal);
        if (null != this.valueTraversal)
            result.add(this.valueTraversal);
        return Collections.unmodifiableList(result);
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
@author Daniel Kuppitz (http://gremlin.guru)
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/map/PropertyMapStep.java