How does hibernate lazy loading work

Please see the below example 1. My service. Please tell me the possible solution for this. Can you please give exception stack trace. That would help. A blog about Java and its related technologies, the best practices, algorithms, interview questions, scripting languages, and Python.

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How to enable lazy loading in hibernate Before moving further, it is important to recap the default behavior of lazy loading in case of using hibernate mappings vs annotations.

Contrary to what you might remember if you have used plain Hibernate 2 mapping files before, where all references including collections are loaded eagerly by default. Was this post helpful? Let us know if you liked the post.

I am getting this exception: Any Help: job aborted for the user user1 due to exception: Version mismatch while modifying object. GeneratedValue; import javax. GenerationType; import javax. Id; import javax. NamedQuery; import javax. OneToMany; import javax.

HibernateDaoSupport; import com. ChildDAO; import com. The fetch used here is a fetch keyword that initializes the collection of toys and returns the entity of the child that is qualified. Considering an online store, a common application used widely on the internet, maintains a product catalog.

An entity can manage a series of other entities which can be products in this case. What is the consequence of 1 and 2? When you look through the process 2 you can see that the session is already closed, when the dialogue is rendered. Your application logic has finished processing. If you have not initialized any objects while your session is open, you will not be able to display them.

Have a look on the following diagram, which explains the situations quite well. When you access a not initialized object you will get a LazyInitializationException explaining that the session is already closed. When can this happen? I have mentioned that Hibernate can map relations. Imagine a class department having a number of teams.

If you want to output a list of departments and teams in your JSP, you must not only fetch all instances of department but also all instances of teams which are associated with one of the departments you are retrieving. ManyToMany; import javax. Set ;. CascadeType ;. Column ;. Entity ;. JoinColumn ;. JoinTable ;. ManyToMany ;.

Table ;. HashSet; import java. Set; import org. Session; import org. SessionFactory; import org.