What is the use of Hibernate batch processing

Question

I am new to hibernate i have doubt in hibernate batch processing, i read some tutorial for hibernate batch processing they said

Session session = SessionFact         


        

Answer 1

As I explained in this article, batch processing allows you to optimize writing data.

However, the usual advice of flushing and clearing the Hibernate Session is incomplete.

You need to commit the transaction at the end of the batch to avoid long-running transactions which can hurt performance and, if the last item fails, undoing all changes is going to put a lot of pressure on the DB.

Therefore, this is how you should do batch processing:

int entityCount = 50;
int batchSize = 25;

EntityManager entityManager = entityManagerFactory().createEntityManager();

EntityTransaction entityTransaction = entityManager.getTransaction();

try {
    entityTransaction.begin();

    for (int i = 0; i < entityCount; i++) {
        if (i > 0 && i % batchSize == 0) {
            entityTransaction.commit();
            entityTransaction.begin();

            entityManager.clear();
        }

        Post post = new Post(
            String.format("Post %d", i + 1)
        );

        entityManager.persist(post);
    }

    entityTransaction.commit();
} catch (RuntimeException e) {
    if (entityTransaction.isActive()) {
        entityTransaction.rollback();
    }
    throw e;
} finally {
    entityManager.close();
}