Looking at the documentation again, we found a simple Hello-World example and tried to understand it. The entities were annotated with @NodeEntity, that was simple, so we added the annotation to our domain classes too. Relationships got their own annotation named @RelationshipEntity. Property fields are taken care of automatically.

It's time to put this to a test. How can we be assured that a field is persisted to the graph store? There seemed to be two possibilities. First was to get a GraphDatabaseContext injected and use its getById() method. The other one was a Finder approach. But let's try to keep things simple. How can we persist an entity and how to get its id? Looking at the documentation revealed that there are a bunch of methods introduced to the entities by the aspects. That's not obvious, but we found the two that would help here - entity.persist() and entity.getNodeId().

So our test looked like this.

@Autowired GraphDatabaseContext graphDatabaseContext;

@Test public void persistedMovieShouldBeRetrievableFromGraphDb() {
    Movie forrestGump = new Movie("Forrest Gump", 1994).persist();
    Movie retrievedMovie = graphDatabaseContext.getById(forrestGump.getNodeId());
    assertEqual("retrieved movie matches persisted one",forrestGump,retrievedMovie);
    assertEqual("retrieved movie title matches","Forrest Gump",retrievedMovie.getTitle());
}

    

That worked! But what about transactions? We didn't declare the test to be transactional. After further reading we learned that persist() creates an implicit transaction - so that was like an EntityManager would behave. Ok, now we're getting somewhere. We also learned that for more complex operations on the entities we'd need external transactions.