Neo4j Spring Data NodeEntity use String as #id - neo4j

Question

I'm trying to use a java.lang.String as the #Id of a NodeEntity.
#NodeEntity(label = "MachineType")
public class MachineType {
#Id private String id;
....
It should be possible acording to the spring data neo4j docu:
While an id is still required on all entities, the behavior has been
simplified by introducing the new #Id annotation. It replaces both
#GraphId and the primary attribute and can be placed on any attribute
with a simple type.
When I'm trying to insert I get a:
{
"cause": null,
"message": "Id must be assignable to Serializable!: null"
}
Which is strange, because String implements the Serializable.
Anyone has an idea where to search next?

Answer 1

I think that you cannot use anything else as an ID. Keep in mind that this Long number will be reused if you delete the node.
I use UUID plugin to generate true unique keys and when I use spring-data-rest I use BackendIdConverter to change the id to the uuid for the resources that I expose.
Example:
Model:
#NodeEntity
#Data
public class Target {
#Id #GeneratedValue Long id; // <----Neo4j id
private String uuid; // <----My Key
#Version Long version;
private List<String> labels = new ArrayList<>();
#Relationship(type = "HAS_MEDIA", direction=Relationship.OUTGOING)
private List<Gallery> media = new ArrayList<>();
}
Convert resource id to my key:
#Component
public class MovieIdConverter implements BackendIdConverter {
#Autowired MovieRepo movieRepository;
#Override
public Serializable fromRequestId(String id, Class<?> entityType) {
Movie movie = movieRepository.findByUuid(id);
return (Serializable) movie.getId();
}
#Override
public String toRequestId(Serializable serializable, Class<?> aClass) {
Long id = (Long) serializable;
Optional<Movie> movie = movieRepository.findById(id);
if (movie.isPresent()) return movie.get().getUuid();
return null;
}
#Override
public boolean supports(Class<?> aClass) {
return Movie.class.equals(aClass);
}
}