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JPA Lifecycle Callback Events

Typical Entity Life-cycle

  • Persist   - Creating Entity for the first time.
  • Merge   - Updating detached Entity
  • Load     - Loading Entity from Database
  • Delete   - Deleting Entity from Database


JPA provides total of 6 Annotations for Life-Cycle Callback events.

  1. @PrePersist
  2. @PostPersist
  3. @PreUpdate
  4. @PostUpdate
  5. @PreRemove
  6. @PostLoad


Following two ways to utilize the above annotations.

Case 1: Defining inside Entity class

Any method can be annotated with one or all annotations, though they should follow these rules.


  1.  Method can have any name
  2.  No parameters
  3.  Return type of void
  4.  Method should not be final or static
  5.  No Checked exceptions should be thrown
  6.  Any annotation can be only used on one method


Example Code Snippet - 1

@Entity
public class Employee implements Serializable {
...

@PrePersist
@PostPersist
@PreUpdate
@PostUpdate
@PreRemove
@PostLoad
public void updateDate() {
    // this method will executed on all the lifecycle events.
}
}

Way 2 : Using Entity Listeners Classes
This is very nice way of using the annotations.

Example Code Snippet - 2


@EntityListeners({LastAccessDateListener.class})
public class Employee implements NamedEntity {
...
}

public class LastAccessDateListener {
@PrePersist
@PostPersist
@PreUpdate
@PostUpdate
@PreRemove
@PostLoad
public void updateDate(Employee e) {
  // this method is in totally separate class
}

}

LastAccessDateListener class doesn't have to be annotated or extend any other class.

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