onSave() (for any Entity saved with Hibernate/Spring Data Repositories)

Question

If my Entity has calculated fields should be update before saving to database (db insert or update) How can I hook a method call before Hibernate o

Answer 1

I think the best option for you are EntityListener using the @PrePersist and @PreUpdate annotations, create the configuration for your entity listener and you will get access to each instance that you want to save, this method is being called each time you are trying to persist or update something with hibernate or spring data repositories

public class EntityToPersistListener{

   @PrePersist
   @PreUpdate
   public void methodExecuteBeforeSave(final EntityToPersist reference) {
      //Make any change to the entity such as calculation before the save process
      reference.setAmount(xxxx)
    }

}

You just need to add an annotation above your entity bean

@Entity
@Table(name = "", schema = "", catalog = "")
@EntityListeners(EntityToPersistListener.class)
public class EntityToPersist implements Serializable {

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