@Override
            public boolean allow(final Object id) {
                return id instanceof Number || id instanceof String;
            }
Manages identifiers of type {@code Long}. Will convert any class that extends from {@link Number} to a
{@link Long} and will also attempt to convert {@code String} values
tinkergraph-gremlin/src/main/java/org/apache/tinkerpop/gremlin/tinkergraph/structure/AbstractTinkerGraph.java