where is the best palce to count the lazy load property using JPA
- by Ke
Let's say we have a "Question" and "Answer" entity,
@Entity
public class Question extends IdEntity {
@Lob
private String content;
@Transient
private int answerTotal;
@OneToMany(fetch = FetchType.LAZY)
private List<Answer> answers = new ArrayList<Answer>();
......
I need to tell how many answers for the question every time Question is queryed. So I need to do count:
String count = "select count(o) from Answer o WHERE o.question=:q";
My question is, where is the best place to do the count? (Because I did a lot of query about Question entity, by date, by tag, by category, by asker, etc. It is obviously not a good solution to add count operation in each query.
My first attempt is to implement a @PostLoad listener, so every time Question entity is loaded, I do count. However, EntityManager cannot be injected in listener. So this way does not work.
Any hint?
