basics: saving an object graph

someone12345 · **Joined:** Sun Apr 16, 2006 1:02 pm **Posts:** 12

Hibernate version:
3.2

Hi!

Urls holds urls and gzhtml holds the gzipped HTML code. Pretty simple.

Code:

public class Urls 
 { 
    @Id 
    @GeneratedValue( generator = "hibernate-uuid" ) 
    private String id; 
 
    @Column( name = "url" ) 
    private String url; 
 
    @OneToOne 
    @PrimaryKeyJoinColumn 
    private GzHtml gzHtml; 

Code:

 public class GzHtml 
 { 
    @Id 
    @Column( name = "url_id" ) 
    private String urlId; 
 
    @Column( name = "html" ) 
    private byte[] html; 

Now I simply want to save a new entity but the following code only saves the Urls entity, not GzHtml. Why? What am I doing wrong?

Code:

       Urls u = new Urls(); 
       u.setUrl( url.toString() ); 
        
       GzHtml h = new GzHtml(); 
       h.setHtml( Utility.compress( html ) ); 
 
       u.setGzHtml( h ); 
       session.save( u ); 

batmat · **Posted:** Sun Feb 04, 2007 11:32 am

You must set the Cascade attribute on the "parent" object. Here it is Cascade.SAVE or something like this (I don't use annotations but it's the same principle).

If you don't put the cascade property, you will have to call save on each objects.

someone12345 · **Joined:** Sun Apr 16, 2006 1:02 pm **Posts:** 12

Code:

@OneToOne(cascade = CascadeType.ALL)

batmat · **Posted:** Sun Feb 04, 2007 12:58 pm

someone12345 wrote:

Code:

@OneToOne(cascade = CascadeType.ALL)

Yes, if this is a parent/child relationship you have. Putting this, you ask hibernate to propagate saves, updates, deletes and so on.

But pay attention, I don't know if it's the same for hibernate annotations CascadeType class, but it would be quite coherent : settting ALL with classical/old XML configuration style does not include delete-orphan rule...