Saving RelationshipEntity not working

This might help you You need to change the direction of the relationship in your entity Mashape, (entity corresponding to the @StartNode of your @RelationshipEntity TagOnObjectEvaluation).

@NodeEntity
class Mashape {

   // ...
   @RelatedToVia(type = RelTypes.Tag.TAG_ON_OBJECT_EVALUATION, direction = Direction.OUTGOING)
   private Set<TagOnObjectEvaluation> tagOnObjectEvaluations = new HashSet<TagOnObjectEvaluation>();    

}

   @RelatedToVia(type = RelTypes.Tag.TAG_ON_OBJECT_EVALUATION)
   private Set<TagOnObjectEvaluation> tagOnObjectEvaluations = new HashSet<TagOnObjectEvaluation>();    

I hope this helps you . MicTech is right.
A RelationshipEntity is represented by an edge in the graph, not a node, and currently Repository implementations are applicable only for objects which can be persisted as nodes. This should not cause you any problems.

To fix the issue you can do I think I somehow solved this with the following steps:
Replaced saving the RelationshipEntity with saving the modified NodeEntity Making such modifying operations sequential (previously this could happen in parallel) Encapsulate the modifying operation in a transaction Fixed a bug where in the same transaction the same entity was saved twice (without changing again in the meantime) Fetching the entity again at the beginning of the transaction in order to have the latest state available

hope this fix your issue As always it depends ...
And in this case it depends on what you intend to do with the comments. Are they themselves an entrypoint into your graph ? Do you intend to search on the content ? Do you intend to find all the comments in a specific timeframe ? If so it definitely makes sense to have the comments as nodes.

To fix this issue How about relying on an abstract class with the common basics and inherit each necessary Role from it?

abstract class BaseRelationship {
  @Id
  @GeneratedValue
  private Long relationshipId;

  @Property  
  private String title;

  [...]
}

@RelationshipEntity(type = "PLAYED_IN")
public class Role extends BaseRelationship {
  [...]
}