Transaction-bound Events
As of Spring 4.2, the listener of an event can be bound to a phase of the transaction. The typical example is to handle the event when the transaction has completed successfully. Doing so lets events be used with more flexibility when the outcome of the current transaction actually matters to the listener.
You can register a regular event listener by using the @EventListener annotation.
If you need to bind it to the transaction, use @TransactionalEventListener.
When you do so, the listener is bound to the commit phase of the transaction by default.
The next example shows this concept. Assume that a component publishes an order-created event and that we want to define a listener that should only handle that event once the transaction in which it has been published has committed successfully. The following example sets up such an event listener:
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Java
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Kotlin
@Component
public class MyComponent {
@TransactionalEventListener
public void handleOrderCreatedEvent(CreationEvent<Order> creationEvent) {
// ...
}
}@Component
class MyComponent {
@TransactionalEventListener
fun handleOrderCreatedEvent(creationEvent: CreationEvent<Order>) {
// ...
}
}The @TransactionalEventListener annotation exposes a phase attribute that lets you
customize the phase of the transaction to which the listener should be bound.
The valid phases are BEFORE_COMMIT, AFTER_COMMIT (default), AFTER_ROLLBACK, as well as
AFTER_COMPLETION which aggregates the transaction completion (be it a commit or a rollback).
If no transaction is running, the listener is not invoked at all, since we cannot honor the
required semantics. You can, however, override that behavior by setting the fallbackExecution
attribute of the annotation to true.
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