Spring Boot. Doing a saveAndFlush with modifying an entity results to unsaved trancient exception

Question

I have a complex entity:

public class Task {
   @OneToOne(orphanRemoval=true, mappedBy="parent")
   @Cascade(value = CascadeType.ALL) (org.hibernate.annotations ... package)
   private Executor executor;
...
}

public class Executor {
   @OneToOne
   @JoinColumn
   private Task parent;

   @ManyToOne
   @Cascade(value = CascadeType.ALL)
   private List<Property> propList = new LinkedList<Property>();
}

Generally, it's a 'Task', which forms an 'Executor', and 'Executor' is filled in with some specific properties.

If I do this in a regular manner, meaning:

@Service
public class Service {
   @PostConstruct
   private void test() {
      Task task = new Task();
      Executor ex = new Executor();
      List<Property> props = ex.getProperties();
      ... forming and adding some properties
      taskDao.saveAndFlush(task);
   }

Everything is fine and the Task get's properly stored.

But since this is simplified, and I need to store the Task the moment I get one, meaning, right after the definition, and store it (flushing, no flushing, dividing into a separate method with transactioning),

@Service
public class Service {
   @PostConstruct
   private void test() {
      Task task = new Task();
      taskDao.saveAndFlush(task); // no change in the exception if I properly move this out to a separate method with @Transactional
      Executor ex = new Executor();
      List<Property> props = ex.getProperties();
      ... forming and adding some properties
      taskDao.saveAndFlush(task);
   }

I get the "unsaved transaction", which is pointing to the second "saveAndFlush".

And this is only achievable if I fill in the Properties, meaning that commenting out the "forming properties" part, everything is working well.

The cascade is ALL (the full list, held in org.hibernate.annotations...), so I'm having doubts for forgetting to specify "Cascade".

Answer 1

saveAndflush does not change the entity to managed state, you need to use managed entity returned by this method. Try this solution:

@PostConstruct
private void test() {
   Task task = new Task();
   task = taskDao.saveAndFlush(task);  // reassign
   Executor ex = new Executor();
   List<Property> props = ex.getProperties();
   ... forming and adding some properties
   taskDao.saveAndFlush(task);
}