Any nice way to make two immutable objects refer to eachother?

Question

Take these two Java classes:

class User {
   final Inventory inventory;
   User (Inventory inv) {
       inventory = inv;
   }
}

class Inventory {
   final User         


        

Answer 1

You can do it if you don't need to inject one of the objects.

class User {
   private final Inventory inventory;
   User () {
       inventory = new Inventory(this);
   }
}