java - Is required new instance of LIST or SET in entity? -


this question has answer here:

i noticed in tutorials mapping columns in hibernate, initialize list(set). difference when don't use "new" , new arraylist()? can use new linkedlist() too? , set? same in list? , there same difference across versions of hibernate?

@entiy public class student implements serializable{ private list<string> subjects1; private list<string> subjects2 = new arraylist(); }

or

@entiy public class student implements serializable{ private set<string> subjects1; private set<string> subjects2 = new hashset(); }

like other collection, need create instance before can add elements. when load entity database, collection created, don't need it.


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