Hibernate batch processing with JpaRepository, JpaContext and PersistenceContext

As you can learn from How to batch INSERT and UPDATE statements with Hibernate (by Vlad Mihalcea), by default, Hibernate doesn't have the batch feature active. In order to activate it, just configure the hibernate.jdbc.batch_size property (e.g. between 5 and 30) as in the above article. For example, you can configure it depending on dialect bach size like this:

public static int batchSize() {

 return Integer.valueOf(Dialect.DEFAULT_BATCH_SIZE);

}

properties.put("hibernate.jdbc.batch_size", String.valueOf(batchSize()));  

Now, let's see three examples of Spring 4 MVC approaches that uses Hibernate batch for some inserts:

- Using JpaRepository:

public interface ProductRepository extends JpaRepository<Product, Long> {

 // NOPE

}

And ...

@Autowired

private ProductRepository productRepository;

...

@Override      

@Transactional

public void withBatching(int n) {

 // preparing the products

 ArrayList<Product> productsInBatch = new ArrayList<>();

 for (int i = 0; i < n; i++) {

      Product p = new Product(i);

      productsInBatch.add(p);

 }                

 long start = System.nanoTime();

 // persist via batching

 productRepository.save(productsInBatch);

 LOG.log(Level.INFO, "INSERTED {0} PRODUCTS IN: {1} MILISECONDS.",

         new Object[]{n, TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start)});        

}

The complete example is available here.

- Using JpaContext:

@Autowired

private JpaContext jpaContext;

...

@Override

@Transactional

public void withBatching(int n) {

 EntityManager em = jpaContext.getEntityManagerByManagedType(Product.class);

 long start = System.nanoTime();

 int batchSize = ...;

 // persist via batching        

 for (int i = 0; i < n; i++) {

      Product p = new Product(i);

      em.persist(p);

      // Flush a batch of inserts and release memory

      if (i % batchSize == 0 && i > 0) {

          em.flush();

          em.clear();

      }

  }

  

  LOG.log(Level.INFO, "INSERTED {0} PRODUCTS IN: {1} MILISECONDS.",

          new Object[]{n, TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start)});

}

The complete example is available here.

- Using PersistenceContext:

@PersistenceContext

private EntityManager entityManager;

And ...

@Autowired

private ProductDAO productDAO;

 @Override

 @Transactional

 public void withBatching(int n) {

  long start = System.nanoTime();

  // persist via batching    

  productDAO.persistWithBatching(n);

  LOG.log(Level.INFO, "INSERTED {0} PRODUCTS IN: {1} MILISECONDS.",

          new Object[]{n, TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - start)});

}

The complete example is available here.

For a batch size of 15, in all examples you should get an output as below: