I'm using the IndexedCollections that have recently been fixed. I seem to be getting random situations where the ordercolumn gets a wrong number assigned and I seem to be having retrieval issues at times.

I have not been able to write a test case that reproduces the issue yet although I do seem to get this frequently in our website.

The basic scenario is this:

• There is a course
• You add a module to the course. You then get automatically redirected to another page to add assets to the module based on the id of the just saved module
• This page sometimes generates an ObjectNotFoundException exception when we try to retrieve the just created module by the past id
• A reload will load the module correctly, even though the index may still be offset incorrectly

So, there are two problems here:
1. Sometimes a module that has just been saved is not retrievable
2. Sometimes the indexcolumn is not properly updated. For instance on a course with 7 modules, adding a new one suddenly generated an indexcolumn value of 4

The two seem to be related I can't yet say if they occur together 100%.
Number 1 suggests a transactional issue but the save happens in a regular transactional context (Spring managed + opensessioninview) and the issue appears across two pages.

@Entity
@DiscriminatorValue(value = "CRS")
@Indexed
public class Course extends Group<CourseMember> {

	private List<Module> modules = new ArrayList<Module>();

	@OneToMany(cascade=CascadeType.ALL,fetch=FetchType.LAZY, mappedBy="course",orphanRemoval=true)
	@OrderColumn
	@Cache(usage=CacheConcurrencyStrategy.READ_WRITE,region=CacheRegion.COURSE)
	public List<Module> getModules() {
		return modules;
	}

    [...]
}

@Entity
@Table
@Cache(usage=CacheConcurrencyStrategy.READ_WRITE,region=CacheRegion.COURSE)
public class Module implements Serializable{

	private Long id;
	private Course course;

	@Id
	@GeneratedValue(strategy = GenerationType.AUTO)
	@Column(updatable = false, insertable = false)
	public Long getId() {
		return id;
	}

	@ManyToOne(fetch=FetchType.LAZY,optional=false)
	@JoinColumn(nullable=false, insertable= true, updatable=false)
	@NotNull
	public Course getCourse() {
		return course;
	}
     [...]
}

I save the module like this

                boolean nw = module.getId() == null;
		
		module = (Module) dao.saveObject(module);
		
		if(nw){
			Course course = module.getCourse();
			course.getModules().add(module);
			dao.save(course);
		}
		
		return module;