在Neo4J / Scala中防止延迟评估

Question

I've written a DAO that performs a traversal using GraphDatabaseService.traversalDescription(), and maps the results into a data structure of the form Map[X, Map[Y, Seq[X]] .

I'm getting a NotInTransactionException when trying to evaluate the data structure later on.

I've tried to use the toList method to force any ResourceIterators to eagerly evaluate. I now have problems with NodeProxy.

Any suggestions?

Answer 1

In order to materialise the Neo4J lazy data structures:

• Iterables / Seqs required a .toList
• Maps (at all depths) required a .toList.toMap