Hi All,

I am facing this annoying issue with @OneToOne mapping.


Set up is very simple.

class User {

@OneToMany(cascade = {CascadeType.PERSIST,CascadeType.MERGE,CascadeType.REFRESH},mappedBy = "user",fetch=FetchType.EAGER)

private List<UserImage> userImagCollection;

public void addImage(UserImage image) {
if(userImagCollection == null) {
userImagCollection = new ArrayList<UserImage>();
}
image.setUser(this);
userImagCollection.add(image);

}


}

class UserImage {

@TableGenerator(name="tg", table="dw_pk_table",
pkColumnName="name", valueColumnName="value",pkColumnValue="UserImage_id",
allocationSize=10
)
@GeneratedValue(strategy=GenerationType.TABLE, generator="tg")
@Column(name = "id", nullable = false)
private long id;

@OneToOne(cascade = CascadeType.ALL, mappedBy = "userImage")
private Image image;
@JoinColumn(name = "usr_id", referencedColumnName = "usr_id")
@ManyToOne
private User user;
}


class Image

{
public class Image implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@GeneratedValue(generator = "myForeignGenerator")
@org.hibernate.annotations.GenericGenerator(
name = "myForeignGenerator",
strategy = "foreign",
parameters = @Parameter(name = "property", value ="userImage")
)
@Column(name = "id", nullable = false)
private long id;
@Lob
@Column(name = "img")
private byte[] img;
@JoinColumn(name = "id", referencedColumnName = "id", insertable = false, updatable = false)
@OneToOne
private UserImage userImage;

}


Simplified veriosn of code.


UserImage userImage = new UserImage();
userImage

UserImage userImage = new UserImage();
userImage.setImage(image);
image.setUserImage(userImage);
user.addImage(userImage);

entitymanger.merge(user)


I think i have wired all the ends.

but merge throws

ed: Db operation failed: Could not update: user: org.hibernate.id.IdentifierGene
rationException: attempted to assign id from null one-to-one property: userImage
: attempted to assign id from null one-to-one property: userImage



I know the reason it is happening ..The reason is userImage object id is null but hibernate should able to handle it. Even if i am creating a new UserImage object , hibernate should get the id from db as per generation strategy and sit in child object (image ) save the data.

In my view that is what the transitive persistance is.

Thanks in advance..

Hi,
Did you solve this problem?.

Thanks
Rohit