default <Tx extends Transaction> Tx tx(final Class<Tx> txClass) {
        throw new UnsupportedOperationException("This Graph does not support multiple transaction types - use tx() instead");
    }
Configure and control the transactions for those graphs that support this feature. Graphs that support multiple
transaction models can use this method expose different sorts of {@link Transaction} implementations.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/structure/Graph.java