java - Hibernate mapping for different items in the same table

Question

I have the following three classes [Promotion, Product and Image]. Promotion has an Image. Product has list/collection of Image's. In the future there may be new classes that also has Image or Collection of Image's.

I would like to put all images in the same image table (eg:: image_table). It means that the image of Promotion and the collection of images in Product are all going to go into the same table.

I can't put for instance two @OneToMany/@ManyToOne annotations in Image class because then there will be two different foreign keys (Promotion_FK and Product_FK) in Image table (eg:: image_table). In the future if there are more classes that has image then I have to add additional @OneToMany/@ManyToOne annotations.

1. Is there a way to map this feature in Hibernate?

2. If my design is not good, in the real world how do they store images that belongs to different classes in the same table?

Answer 1

Try to use Unidirectional mapping then

e.g. Promotion having Image, Product having Image's, but not Vice Versa