Lifecycle Hooks

You can use lifecycle hooks to run some code when entity gets persisted. You can mark any of entity methods with them, you can also mark multiple methods with same hook.

All hooks support async methods with one exception - @OnInit.

• @OnInit is fired when new instance of entity is created, either manually em.create(), or automatically when new entities are loaded from database

• @BeforeCreate() and @BeforeUpdate() is fired right before we persist the entity in database

• @AfterCreate() and @AfterUpdate() is fired right after the entity is updated in database and merged to identity map. Since this event entity will have reference to EntityManager and will be enabled to call entity.init() method (including all entity references and collections).

• @BeforeDelete() is fired right before we delete the record from database. It is fired only when removing entity or entity reference, not when deleting records by query.

• @AfterDelete() is fired right after the record gets deleted from database and it is unset from the identity map.

@OnInit is not fired when you create the entity manually via its constructor (new MyEntity())

Limitations of lifecycle hooks

Hooks are executed inside the commit action of unit of work, after all change sets are computed. This means that it is not possible to create new entities as usual from inside the hook. Calling em.flush() from hooks will result in validation error. Calling em.persist() can result in undefined behaviour like locking errors.

The internal instance of EntityManager accessible under wrap(this).__em is not meant for public usage.