Fire Hibernate custom event listener before auto-triggered default listeners

I have an example for you which creates data history for person entity. Hope it helps.

I had to make a helper interface:

public interface DataHistoryAware {    public DataHistory getDataHistory();    public void setDataHistory(DataHistory dataHistory);}

This is the listener implementation:

public class DataHistoryListener {   @PrePersist    public void setCreateDataHistory(DataHistoryAware model) {        //set creationDate        DataHistory dataHistory = model.getDataHistory() == null ? new DataHistory() : model.getDataHistory();        dataHistory.setCreationDate(new Date());        model.setDataHistory(dataHistory);     }@PostUpdate    public void setUpdateDataHistory(DataHistoryAware model) {        DataHistory dataHistory = model.getDataHistory() == null ? new DataHistory() : model.getDataHistory();        dataHistory.setLastModificationDate(new Date());        model.setDataHistory(dataHistory);    }}

The person entity:

@Entity@EntityListeners(DataHistoryListener.class)@Table(name="person")public class Person implements Serializable, DataHistoryAware {@Column(name = "full_name", length = 255, nullable = false)    private String fullName;@OneToOne(cascade = CascadeType.PERSIST)@JoinColumn(name = "data_history_id", nullable = false)private DataHistory dataHistory;public String getFullName() {        return this.fullName;    }    public void setFullName(String fullName) {        this.fullName = fullName;    }public DataHistory getDataHistory() {        return dataHistory;    }    public void setDataHistory(DataHistory dataHistory) {        this.dataHistory = dataHistory;    }}

This implementation creates a datahistory record for person entity before persist, and will update it before merge. The datahistory property has a not-null constraint, so this is the same thing like your problem with the not-null property of the contact entity. Hope it was useful.

IMHO, what you are doing is overkill. You can achieve the same thing with Interceptor

If you already know this and choose to override PreInsetEventListener for some reasons(interest to know), then you need to start from overriding default implementations of org.hibernate.event.def.AbstractSaveEventListener.For example, org.hibernate.event.def.DefaultSaveEventListener.

See that Nullability and foreign key constraint check happens in 'AbstractSaveEventListener.performSaveOrReplicate' and EntityActions are added to the action queue. These actions are executed during session flush and this is when you get call to your PreInsertEventListener from EntityActions.