@Override
        public CloseableIterator<R> execute(final ServiceCallContext ctx, final Traverser.Admin<I> in, final Map params) {
            final Object result = lambda.apply(ctx, in, params);
            return CloseableIterator.of(result instanceof Iterator ? (Iterator<R>) result : IteratorUtils.of((R) result));
        }
Does this service support all of the specified types.
tinkergraph-gremlin/src/main/java/org/apache/tinkerpop/gremlin/tinkergraph/services/TinkerServiceRegistry.java