private List<VertexProperty<?>> getValue(final Vertex vertex, final String key) {
        return this.computeProperties.getOrDefault(vertex, Collections.emptyMap()).getOrDefault(key, Collections.emptyList());
    }
@author Marko A. Rodriguez (http://markorodriguez.com)
tinkergraph-gremlin/src/main/java/org/apache/tinkerpop/gremlin/tinkergraph/process/computer/TinkerGraphComputerView.java