Hibernation annotations, specify column default value

Question

I have a domain object and annotated as follows

 @Entity
 @Table(name = "REQUEST")
 public class Request {

  /**
   * Unique id for this request
   */
@Id
@GeneratedValue
@Column(name = "EQ_ID")
private long requestId;
/**
 * 
 */
@Column(name = "EMAIL_ID")
private String emailId;
/**
 * 
 */
@Column(name = "REQUEST_DATE")
private Date requestDate;
/**
*Getters/setters omitted
*/
 }

The column Request_date cannot be null and as per the DDL the default value is sysdate (oracle DB). How do I annotate this field so that if the requestDate property is null,hiberanate automatically inserts sysdate.? Currently it throws error when the field is null,which is very obvious as it cannot be null as per the DB constraints. How do I go about this? One alternative is to mark this field as transient and the inserts work fine. But the negative aspect is that, I will not be able to retrieve the value (of request_date column).

Answer 1

Assign a default value to the field:

private Date requestDate = new Date();

Answer 2

you can put default value in columnDefination. Something similar to

   @Column(name = “REQUEST_DATE”, nullable = false, columnDefinition = “date default sysdate″)

Answer 3

Make the default in oracle for the column SYSDATE:

ALTR TABLE APP MODIFY (REQUEST_DATE DEFAULT SYSDATE);

Then, from Hibernate's perspective it can be nullable.

Hibernate will save a NULL to the database, and Oracle will convert that to SYSDATE, and everyone will be happy.

Answer 4

This is a missing feature in hibernate annotations. Also there exist some workaround as Yok has posted. The problem is that the workaround is vendor dependent and might not work for all DB. In my case,Oracle, it isn't working and has been reported as a bug.