java - HIbernate update with null on onetomany relation -

i have following tables :

• product (id_product, name)
• property (id_property, name)
• product_properties (id_product, id_property)

(all fields not nullable)

and following hibernate mapping :

class product {     @id     private integer id;      @onetomany(mappedby="product")     @cascade({cascadetype.all})     private set<productproperties> productproperties = new hashset<productproperties)(0);      (...)     } 

when update product class adding or removing rows "productproperties" field, rows updated correctly in product_properties table.

the problem when "productproperties" null or empty, hibernate throws constraintviolationexception.

since need "productproperties" empty sometimes, there proper solution problem (something @zerotomany annotation) ?

the answer given dev blanked in comments. solution :

@onetomany(mappedby="foo", orphanremoval=true)