I have a book that says one-to-one association needs to be bidirectional, is this correct? Even if I always load from one side of the relation?


Regards,

BTJ

this one is answered by my recent example:

http://forum.hibernate.org/viewtopic.php?t=956962&highlight=

No they don't *need* to be bidirectional. The example shows both cases, unidirectional and bidirectional

Forgot to mention that I am using generator class = foreign, and then it looks like I have to add a mapping the other way by addding param name=property>object/> to my mapping file..?

All depends from which side you are loading. If you are loading in the object that maps to the table with the foreign key, then you only have to do it on that side. If however, you wish to load that object into the object to which that foreign key maps, then you have to do it on both sides. This latter case, though it tends to make more sense in regard to the relationship, feels nothing short of a hack. Perhaps in H4 this will be corrected.

Yes, the back and forth discusion jt_1000 and I had shows both how to load from one side only (the relating from side) and how to load from both sides. We also discussed the lack of a way to load from the referring side (the to side) only.

For instance, supposed B relates to A via a foriegn key A_id which points to the PK in A. B can load A into its mapping as one to one. A, however, cannot load B into its mapping without the B having been mapped to load A. This is the part that feels like a hack to me. It is both limiting and short-sighted.