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When does JPA persistence context end?


When does JPA persistence context end?

By : Kaivalya Ram
Date : November 23 2020, 03:01 PM
I wish this help you A persistence context ends when EntityManager.close() is called. Here's an example.
Another example taken from the link provided in the question:
code :
MagazineId mi = new MagazineId();
mi.isbn = "1B78-YU9L";
mi.title = "JavaWorld";

// updates should always be made within transactions; note that
// there is no code explicitly linking the magazine or company
// with the transaction; JPA automatically tracks all changes
EntityManager em = emf.createEntityManager();
em.getTransaction().begin();
Magazine mag = em.find(Magazine.class, mi);
mag.setPrice(5.99);
Company pub = mag.getPublisher();
pub.setRevenue(1750000D);
em.getTransaction().commit();

// or we could continue using the EntityManager...
em.close();


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What is the difference between Transaction-scoped Persistence context and Extended Persistence context?

What is the difference between Transaction-scoped Persistence context and Extended Persistence context?


By : Mattia Matteucci
Date : March 29 2020, 07:55 AM
With these it helps The difference is clearly explained in the JSR-220 Enterprise JavaBeans 3.0 specification:
5.6 Container-managed Persistence Contexts
What is a bulk update in the context of JPQL queries and JPA persistence context?

What is a bulk update in the context of JPQL queries and JPA persistence context?


By : Saurabh Singh
Date : March 29 2020, 07:55 AM
With these it helps "BULK UPDATE" is clearly an update using a Query such as "UPDATE MyEntity SET field1 = val1 WHERE field2 < 345" (just as BULK DELETE is a DELETE query). A normal update is where you update a field of a managed entity directly, using a setter.
Rationale : well the whole point of bulk update is to not have to load objects into memory, or work out if any of the affected objects are already managed. You'll likely find that most JPA implementations will evict possibly affected objects out of the L2 cache on performing a BULK UPDATE.
Glassfish 3.1.2 "Could not resolve a persistence unit corresponding to the persistence-context-ref-name"

Glassfish 3.1.2 "Could not resolve a persistence unit corresponding to the persistence-context-ref-name"


By : susan
Date : March 29 2020, 07:55 AM
I wish this helpful for you If busctrl.jar isn't a "deployed" component (containing EJBs) then move it into lib/busctrl.jar within the EAR file where it'll be visible on the classpath of the war file.
If it does contain EJBs, then some surgery needs to occur:
What is Persistence Context?

What is Persistence Context?


By : Tim Essig
Date : March 29 2020, 07:55 AM
hope this fix your issue A persistence context handles a set of entities which hold data to be persisted in some persistence store (e.g. a database). In particular, the context is aware of the different states an entity can have (e.g. managed, detached) in relation to both the context and the underlying persistence store.
Although Hibernate-related (a JPA provider), I think these links are useful:
Persistence unit error: javax.persistence.PersistenceException: No Persistence provider for EntityManager named

Persistence unit error: javax.persistence.PersistenceException: No Persistence provider for EntityManager named


By : Ezron Exemplaris
Date : March 29 2020, 07:55 AM
may help you . Well I only had to do a clean and Build to make it work!!! All files were ok and clean only wasn't enough.
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