Does @transactional commit?

Does @transactional commit?

By default, that proxy starts a transaction before your request enters the first method that’s annotated with @Transactional. After that method got executed, the proxy either commits the transaction or rolls it back if a RuntimeException or Error occurred.

Which method of EntityManager would begin the transaction perform your operations and then either commit or rollback your transaction in JPA?

getTransaction defines an EntityTransaction to use in your database interactions. Just like database transactions, you will typically begin the transaction, perform your operations, and then either commit or rollback your transaction.

Should EntityManager be closed?

If you don’t close it your entities will be kept as attached, even after you’re done using them. Your context will be kept alive even when you can no longer access your EM.

What is flush in EntityManager?

Flushing is the process of synchronizing the state of the persistence context with the underlying database. The EntityManager and the Hibernate Session expose a set of methods, through which the application developer can change the persistent state of an entity.

What does EntityManager refresh do?

By invoking EntityManager#refresh(entity) , we can synchronize the current persistence context to the underlying database. In other words, by invoking this method, we can reload the state of a managed entity instance from the database. The existing state of the entity instance is overwritten.

When should we use @transactional annotation?

The @Transactional annotation makes use of the attributes rollbackFor or rollbackForClassName to rollback the transactions, and the attributes noRollbackFor or noRollbackForClassName to avoid rollback on listed exceptions. The default rollback behavior in the declarative approach will rollback on runtime exceptions.

Which method of the JPA EntityManager would you use to force synchronizing the database?

the flush method
To force synchronization of the managed entity to the data store, invoke the flush method of the EntityManager instance.

Does Hibernate flush commit?

By default, Hibernate uses the AUTO flush mode which triggers a flush in the following circumstances: prior to committing a Transaction. prior to executing a JPQL/HQL query that overlaps with the queued entity actions. before executing any native SQL query that has no registered synchronization.

How do I use EntityManager persist?

To become persisted we need to either explicitly call the EntityManager#persist method or make use of the transitive persistence mechanism.

1. Persistent (Managed) A persistent entity has been associated with a database table row and it’s being managed by the currently running Persistence Context.
2. Detached.

What is EntityManager flush?

The EntityManager. flush() operation can be used the write all changes to the database before the transaction is committed. By default JPA does not normally write changes to the database until the transaction is committed. This is normally desirable as it avoids database access, resources and locks until required.

Can private method be transactional?

Yes, it is possible to use @Transactional on private methods, but as others have mentioned this won’t work out of the box.